aboutsummaryrefslogtreecommitdiffstats
path: root/jobs.c
blob: d63c5dd913e5018d5d60d5fa4dddf1c36a67df7d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
/* jobs.c - functions that make children, remember them, and handle their termination. */

/* This file works with both POSIX and BSD systems.  It implements job
   control. */

/* Copyright (C) 1989-2010 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Bash is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Bash.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "config.h"

#include "bashtypes.h"
#include "trap.h"
#include <stdio.h>
#include <signal.h>
#include <errno.h>

#if defined (HAVE_UNISTD_H)
#  include <unistd.h>
#endif

#include "posixtime.h"

#if defined (HAVE_SYS_RESOURCE_H) && defined (HAVE_WAIT3) && !defined (_POSIX_VERSION) && !defined (RLIMTYPE)
#  include <sys/resource.h>
#endif /* !_POSIX_VERSION && HAVE_SYS_RESOURCE_H && HAVE_WAIT3 && !RLIMTYPE */

#if defined (HAVE_SYS_FILE_H)
#  include <sys/file.h>
#endif

#include "filecntl.h"
#include <sys/ioctl.h>
#include <sys/param.h>

#if defined (BUFFERED_INPUT)
#  include "input.h"
#endif

/* Need to include this up here for *_TTY_DRIVER definitions. */
#include "shtty.h"

/* Define this if your output is getting swallowed.  It's a no-op on
   machines with the termio or termios tty drivers. */
/* #define DRAIN_OUTPUT */

/* For the TIOCGPGRP and TIOCSPGRP ioctl parameters on HP-UX */
#if defined (hpux) && !defined (TERMIOS_TTY_DRIVER)
#  include <bsdtty.h>
#endif /* hpux && !TERMIOS_TTY_DRIVER */

#include "bashansi.h"
#include "bashintl.h"
#include "shell.h"
#include "jobs.h"
#include "execute_cmd.h"
#include "flags.h"

#include "builtins/builtext.h"
#include "builtins/common.h"

#if !defined (errno)
extern int errno;
#endif /* !errno */

#if !defined (HAVE_KILLPG)
extern int killpg __P((pid_t, int));
#endif

#define DEFAULT_CHILD_MAX 32
#if !defined (DEBUG)
#define MAX_JOBS_IN_ARRAY 4096		/* production */
#else
#define MAX_JOBS_IN_ARRAY 128		/* testing */
#endif

/* Flag values for second argument to delete_job */
#define DEL_WARNSTOPPED		1	/* warn about deleting stopped jobs */
#define DEL_NOBGPID		2	/* don't add pgrp leader to bgpids */

/* Take care of system dependencies that must be handled when waiting for
   children.  The arguments to the WAITPID macro match those to the Posix.1
   waitpid() function. */

#if defined (ultrix) && defined (mips) && defined (_POSIX_VERSION)
#  define WAITPID(pid, statusp, options) \
	wait3 ((union wait *)statusp, options, (struct rusage *)0)
#else
#  if defined (_POSIX_VERSION) || defined (HAVE_WAITPID)
#    define WAITPID(pid, statusp, options) \
	waitpid ((pid_t)pid, statusp, options)
#  else
#    if defined (HAVE_WAIT3)
#      define WAITPID(pid, statusp, options) \
	wait3 (statusp, options, (struct rusage *)0)
#    else
#      define WAITPID(pid, statusp, options) \
	wait3 (statusp, options, (int *)0)
#    endif /* HAVE_WAIT3 */
#  endif /* !_POSIX_VERSION && !HAVE_WAITPID*/
#endif /* !(Ultrix && mips && _POSIX_VERSION) */

/* getpgrp () varies between systems.  Even systems that claim to be
   Posix.1 compatible lie sometimes (Ultrix, SunOS4, apollo). */
#if defined (GETPGRP_VOID)
#  define getpgid(p) getpgrp ()
#else
#  define getpgid(p) getpgrp (p)
#endif /* !GETPGRP_VOID */

/* If the system needs it, REINSTALL_SIGCHLD_HANDLER will reinstall the
   handler for SIGCHLD. */
#if defined (MUST_REINSTALL_SIGHANDLERS)
#  define REINSTALL_SIGCHLD_HANDLER signal (SIGCHLD, sigchld_handler)
#else
#  define REINSTALL_SIGCHLD_HANDLER
#endif /* !MUST_REINSTALL_SIGHANDLERS */

/* Some systems let waitpid(2) tell callers about stopped children. */
#if !defined (WCONTINUED) || defined (WCONTINUED_BROKEN)
#  undef WCONTINUED
#  define WCONTINUED 0
#endif
#if !defined (WIFCONTINUED)
#  define WIFCONTINUED(s)	(0)
#endif

/* The number of additional slots to allocate when we run out. */
#define JOB_SLOTS 8

typedef int sh_job_map_func_t __P((JOB *, int, int, int));

/* Variables used here but defined in other files. */
extern int subshell_environment, line_number;
extern int posixly_correct, shell_level;
extern int last_command_exit_value, last_command_exit_signal;
extern int loop_level, breaking;
extern int executing_list;
extern int sourcelevel;
extern int running_trap;
extern sh_builtin_func_t *this_shell_builtin;
extern char *shell_name, *this_command_name;
extern sigset_t top_level_mask;
extern procenv_t wait_intr_buf;
extern int wait_signal_received;
extern WORD_LIST *subst_assign_varlist;

static struct jobstats zerojs = { -1L, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, NO_JOB, NO_JOB, 0, 0 };
struct jobstats js = { -1L, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, NO_JOB, NO_JOB, 0, 0 };

struct bgpids bgpids = { 0, 0, 0 };

/* The array of known jobs. */
JOB **jobs = (JOB **)NULL;

#if 0
/* The number of slots currently allocated to JOBS. */
int job_slots = 0;
#endif

/* The controlling tty for this shell. */
int shell_tty = -1;

/* The shell's process group. */
pid_t shell_pgrp = NO_PID;

/* The terminal's process group. */
pid_t terminal_pgrp = NO_PID;

/* The process group of the shell's parent. */
pid_t original_pgrp = NO_PID;

/* The process group of the pipeline currently being made. */
pid_t pipeline_pgrp = (pid_t)0;

#if defined (PGRP_PIPE)
/* Pipes which each shell uses to communicate with the process group leader
   until all of the processes in a pipeline have been started.  Then the
   process leader is allowed to continue. */
int pgrp_pipe[2] = { -1, -1 };
#endif

#if 0
/* The job which is current; i.e. the one that `%+' stands for. */
int current_job = NO_JOB;

/* The previous job; i.e. the one that `%-' stands for. */
int previous_job = NO_JOB;
#endif

/* Last child made by the shell.  */
pid_t last_made_pid = NO_PID;

/* Pid of the last asynchronous child. */
pid_t last_asynchronous_pid = NO_PID;

/* The pipeline currently being built. */
PROCESS *the_pipeline = (PROCESS *)NULL;

/* If this is non-zero, do job control. */
int job_control = 1;

/* Call this when you start making children. */
int already_making_children = 0;

/* If this is non-zero, $LINES and $COLUMNS are reset after every process
   exits from get_tty_state(). */
int check_window_size;

/* Functions local to this file. */

static sighandler wait_sigint_handler __P((int));
static sighandler sigchld_handler __P((int));
static sighandler sigcont_sighandler __P((int));
static sighandler sigstop_sighandler __P((int));

static int waitchld __P((pid_t, int));

static PROCESS *find_pipeline __P((pid_t, int, int *));
static PROCESS *find_process __P((pid_t, int, int *));

static char *current_working_directory __P((void));
static char *job_working_directory __P((void));
static char *j_strsignal __P((int));
static char *printable_job_status __P((int, PROCESS *, int));

static PROCESS *find_last_proc __P((int, int));
static pid_t find_last_pid __P((int, int));

static int set_new_line_discipline __P((int));
static int map_over_jobs __P((sh_job_map_func_t *, int, int));
static int job_last_stopped __P((int));
static int job_last_running __P((int));
static int most_recent_job_in_state __P((int, JOB_STATE));
static int find_job __P((pid_t, int, PROCESS **));
static int print_job __P((JOB *, int, int, int));
static int process_exit_status __P((WAIT));
static int process_exit_signal __P((WAIT));
static int set_job_status_and_cleanup __P((int));

static WAIT job_signal_status __P((int));
static WAIT raw_job_exit_status __P((int));

static void notify_of_job_status __P((void));
static void reset_job_indices __P((void));
static void cleanup_dead_jobs __P((void));
static int processes_in_job __P((int));
static void realloc_jobs_list __P((void));
static int compact_jobs_list __P((int));
static int discard_pipeline __P((PROCESS *));
static void add_process __P((char *, pid_t));
static void print_pipeline __P((PROCESS *, int, int, FILE *));
static void pretty_print_job __P((int, int, FILE *));
static void set_current_job __P((int));
static void reset_current __P((void));
static void set_job_running __P((int));
static void setjstatus __P((int));
static int maybe_give_terminal_to __P((pid_t, pid_t, int));
static void mark_all_jobs_as_dead __P((void));
static void mark_dead_jobs_as_notified __P((int));
static void restore_sigint_handler __P((void));
#if defined (PGRP_PIPE)
static void pipe_read __P((int *));
#endif

static struct pidstat *bgp_alloc __P((pid_t, int));
static struct pidstat *bgp_add __P((pid_t, int));
static int bgp_delete __P((pid_t));
static void bgp_clear __P((void));
static int bgp_search __P((pid_t));
static void bgp_prune __P((void));

#if defined (ARRAY_VARS)
static int *pstatuses;		/* list of pipeline statuses */
static int statsize;
#endif

/* Used to synchronize between wait_for and other functions and the SIGCHLD
   signal handler. */
static int sigchld;
static int queue_sigchld;

#define QUEUE_SIGCHLD(os)	(os) = sigchld, queue_sigchld++

#define UNQUEUE_SIGCHLD(os) \
	do { \
	  queue_sigchld--; \
	  if (queue_sigchld == 0 && os != sigchld) \
	    waitchld (-1, 0); \
	} while (0)

static SigHandler *old_tstp, *old_ttou, *old_ttin;
static SigHandler *old_cont = (SigHandler *)SIG_DFL;

/* A place to temporarily save the current pipeline. */
static PROCESS *saved_pipeline;
static int saved_already_making_children;

/* Set this to non-zero whenever you don't want the jobs list to change at
   all: no jobs deleted and no status change notifications.  This is used,
   for example, when executing SIGCHLD traps, which may run arbitrary
   commands. */
static int jobs_list_frozen;

static char retcode_name_buffer[64];

/* flags to detect pid wraparound */
static pid_t first_pid = NO_PID;
static int pid_wrap = -1;

#if !defined (_POSIX_VERSION)

/* These are definitions to map POSIX 1003.1 functions onto existing BSD
   library functions and system calls. */
#define setpgid(pid, pgrp)	setpgrp (pid, pgrp)
#define tcsetpgrp(fd, pgrp)	ioctl ((fd), TIOCSPGRP, &(pgrp))

pid_t
tcgetpgrp (fd)
     int fd;
{
  pid_t pgrp;

  /* ioctl will handle setting errno correctly. */
  if (ioctl (fd, TIOCGPGRP, &pgrp) < 0)
    return (-1);
  return (pgrp);
}

#endif /* !_POSIX_VERSION */

/* Initialize the global job stats structure and other bookkeeping variables */
void
init_job_stats ()
{
  js = zerojs;
  first_pid = NO_PID;
  pid_wrap = -1;
}

/* Return the working directory for the current process.  Unlike
   job_working_directory, this does not call malloc (), nor do any
   of the functions it calls.  This is so that it can safely be called
   from a signal handler. */
static char *
current_working_directory ()
{
  char *dir;
  static char d[PATH_MAX];

  dir = get_string_value ("PWD");

  if (dir == 0 && the_current_working_directory && no_symbolic_links)
    dir = the_current_working_directory;

  if (dir == 0)
    {
      dir = getcwd (d, sizeof(d));
      if (dir)
	dir = d;
    }

  return (dir == 0) ? "<unknown>" : dir;
}

/* Return the working directory for the current process. */
static char *
job_working_directory ()
{
  char *dir;

  dir = get_string_value ("PWD");
  if (dir)
    return (savestring (dir));

  dir = get_working_directory ("job-working-directory");
  if (dir)
    return (dir);

  return (savestring ("<unknown>"));
}

void
making_children ()
{
  if (already_making_children)
    return;

  already_making_children = 1;
  start_pipeline ();
}

void
stop_making_children ()
{
  already_making_children = 0;
}

void
cleanup_the_pipeline ()
{
  PROCESS *disposer;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);
  disposer = the_pipeline;
  the_pipeline = (PROCESS *)NULL;
  UNBLOCK_CHILD (oset);

  if (disposer)
    discard_pipeline (disposer);
}

void
save_pipeline (clear)
     int clear;
{
  saved_pipeline = the_pipeline;
  if (clear)
    the_pipeline = (PROCESS *)NULL;
  saved_already_making_children = already_making_children;
}

void
restore_pipeline (discard)
     int discard;
{
  PROCESS *old_pipeline;

  old_pipeline = the_pipeline;
  the_pipeline = saved_pipeline;
  already_making_children = saved_already_making_children;
  if (discard && old_pipeline)
    discard_pipeline (old_pipeline);
}

/* Start building a pipeline.  */
void
start_pipeline ()
{
  if (the_pipeline)
    {
      cleanup_the_pipeline ();
      pipeline_pgrp = 0;
#if defined (PGRP_PIPE)
      sh_closepipe (pgrp_pipe);
#endif
    }

#if defined (PGRP_PIPE)
  if (job_control)
    {
      if (pipe (pgrp_pipe) == -1)
	sys_error (_("start_pipeline: pgrp pipe"));
    }
#endif
}

/* Stop building a pipeline.  Install the process list in the job array.
   This returns the index of the newly installed job.
   DEFERRED is a command structure to be executed upon satisfactory
   execution exit of this pipeline. */
int
stop_pipeline (async, deferred)
     int async;
     COMMAND *deferred;
{
  register int i, j;
  JOB *newjob;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);

#if defined (PGRP_PIPE)
  /* The parent closes the process group synchronization pipe. */
  sh_closepipe (pgrp_pipe);
#endif

  cleanup_dead_jobs ();

  if (js.j_jobslots == 0)
    {
      js.j_jobslots = JOB_SLOTS;
      jobs = (JOB **)xmalloc (js.j_jobslots * sizeof (JOB *));

      /* Now blank out these new entries. */
      for (i = 0; i < js.j_jobslots; i++)
	jobs[i] = (JOB *)NULL;

      js.j_firstj = js.j_lastj = js.j_njobs = 0;
    }

  /* Scan from the last slot backward, looking for the next free one. */
  /* XXX - revisit this interactive assumption */
  /* XXX - this way for now */
  if (interactive)
    {
      for (i = js.j_jobslots; i; i--)
	if (jobs[i - 1])
	  break;
    }
  else
    {
#if 0
      /* This wraps around, but makes it inconvenient to extend the array */
      for (i = js.j_lastj+1; i != js.j_lastj; i++)
	{
	  if (i >= js.j_jobslots)
	    i = 0;
	  if (jobs[i] == 0)
	    break;
	}	
      if (i == js.j_lastj)
        i = js.j_jobslots;
#else
      /* This doesn't wrap around yet. */
      for (i = js.j_lastj ? js.j_lastj + 1 : js.j_lastj; i < js.j_jobslots; i++)
	if (jobs[i] == 0)
	  break;
#endif
    }

  /* Do we need more room? */

  /* First try compaction */
  if ((interactive_shell == 0 || subshell_environment) && i == js.j_jobslots && js.j_jobslots >= MAX_JOBS_IN_ARRAY)
    i = compact_jobs_list (0);

  /* If we can't compact, reallocate */
  if (i == js.j_jobslots)
    {
      js.j_jobslots += JOB_SLOTS;
      jobs = (JOB **)xrealloc (jobs, (js.j_jobslots * sizeof (JOB *)));

      for (j = i; j < js.j_jobslots; j++)
	jobs[j] = (JOB *)NULL;
    }

  /* Add the current pipeline to the job list. */
  if (the_pipeline)
    {
      register PROCESS *p;
      int any_running, any_stopped, n;

      newjob = (JOB *)xmalloc (sizeof (JOB));

      for (n = 1, p = the_pipeline; p->next != the_pipeline; n++, p = p->next)
	;
      p->next = (PROCESS *)NULL;
      newjob->pipe = REVERSE_LIST (the_pipeline, PROCESS *);
      for (p = newjob->pipe; p->next; p = p->next)
	;
      p->next = newjob->pipe;

      the_pipeline = (PROCESS *)NULL;
      newjob->pgrp = pipeline_pgrp;
      pipeline_pgrp = 0;

      newjob->flags = 0;

      /* Flag to see if in another pgrp. */
      if (job_control)
	newjob->flags |= J_JOBCONTROL;

      /* Set the state of this pipeline. */
      p = newjob->pipe;
      any_running = any_stopped = 0;
      do
	{
	  any_running |= PRUNNING (p);
	  any_stopped |= PSTOPPED (p);
	  p = p->next;
	}
      while (p != newjob->pipe);

      newjob->state = any_running ? JRUNNING : (any_stopped ? JSTOPPED : JDEAD);
      newjob->wd = job_working_directory ();
      newjob->deferred = deferred;

      newjob->j_cleanup = (sh_vptrfunc_t *)NULL;
      newjob->cleanarg = (PTR_T) NULL;

      jobs[i] = newjob;
      if (newjob->state == JDEAD && (newjob->flags & J_FOREGROUND))
	setjstatus (i);
      if (newjob->state == JDEAD)
	{
	  js.c_reaped += n;	/* wouldn't have been done since this was not part of a job */
	  js.j_ndead++;
	}
      js.c_injobs += n;

      js.j_lastj = i;
      js.j_njobs++;
    }
  else
    newjob = (JOB *)NULL;

  if (newjob)
    js.j_lastmade = newjob;

  if (async)
    {
      if (newjob)
	{
	  newjob->flags &= ~J_FOREGROUND;
	  newjob->flags |= J_ASYNC;
	  js.j_lastasync = newjob;
	}
      reset_current ();
    }
  else
    {
      if (newjob)
	{
	  newjob->flags |= J_FOREGROUND;
	  /*
	   *		!!!!! NOTE !!!!!  (chet@ins.cwru.edu)
	   *
	   * The currently-accepted job control wisdom says to set the
	   * terminal's process group n+1 times in an n-step pipeline:
	   * once in the parent and once in each child.  This is where
	   * the parent gives it away.
	   *
	   * Don't give the terminal away if this shell is an asynchronous
	   * subshell.
	   *
	   */
	  if (job_control && newjob->pgrp && (subshell_environment&SUBSHELL_ASYNC) == 0)
	    maybe_give_terminal_to (shell_pgrp, newjob->pgrp, 0);
	}
    }

  stop_making_children ();
  UNBLOCK_CHILD (oset);
  return (newjob ? i : js.j_current);
}

/* Functions to manage the list of exited background pids whose status has
   been saved. */

static struct pidstat *
bgp_alloc (pid, status)
     pid_t pid;
     int status;
{
  struct pidstat *ps;

  ps = (struct pidstat *)xmalloc (sizeof (struct pidstat));
  ps->pid = pid;
  ps->status = status;
  ps->next = (struct pidstat *)0;
  return ps;
}

static struct pidstat *
bgp_add (pid, status)
     pid_t pid;
     int status;
{
  struct pidstat *ps;

  ps = bgp_alloc (pid, status);

  if (bgpids.list == 0)
    {
      bgpids.list = bgpids.end = ps;
      bgpids.npid = 0;			/* just to make sure */
    }
  else
    {
      bgpids.end->next = ps;
      bgpids.end = ps;
    }
  bgpids.npid++;

  if (bgpids.npid > js.c_childmax)
    bgp_prune ();

  return ps;
}

static int
bgp_delete (pid)
     pid_t pid;
{
  struct pidstat *prev, *p;

  for (prev = p = bgpids.list; p; prev = p, p = p->next)
    if (p->pid == pid)
      {
	prev->next = p->next;	/* remove from list */
	break;
      }

  if (p == 0)
    return 0;		/* not found */

#if defined (DEBUG)
  itrace("bgp_delete: deleting %d", pid);
#endif

  /* Housekeeping in the border cases. */
  if (p == bgpids.list)
    bgpids.list = bgpids.list->next;
  else if (p == bgpids.end)
    bgpids.end = prev;

  bgpids.npid--;
  if (bgpids.npid == 0)
    bgpids.list = bgpids.end = 0;
  else if (bgpids.npid == 1)
    bgpids.end = bgpids.list;		/* just to make sure */

  free (p);
  return 1;
}

/* Clear out the list of saved statuses */
static void
bgp_clear ()
{
  struct pidstat *ps, *p;

  for (ps = bgpids.list; ps; )
    {
      p = ps;
      ps = ps->next;
      free (p);
    }
  bgpids.list = bgpids.end = 0;
  bgpids.npid = 0;
}

/* Search for PID in the list of saved background pids; return its status if
   found.  If not found, return -1. */
static int
bgp_search (pid)
     pid_t pid;
{
  struct pidstat *ps;

  for (ps = bgpids.list ; ps; ps = ps->next)
    if (ps->pid == pid)
      return ps->status;
  return -1;
}

static void
bgp_prune ()
{
  struct pidstat *ps;

  while (bgpids.npid > js.c_childmax)
    {
      ps = bgpids.list;
      bgpids.list = bgpids.list->next;
      free (ps);
      bgpids.npid--;
    }
}

/* Reset the values of js.j_lastj and js.j_firstj after one or both have
   been deleted.  The caller should check whether js.j_njobs is 0 before
   calling this.  This wraps around, but the rest of the code does not.  At
   this point, it should not matter. */
static void
reset_job_indices ()
{
  int old;

  if (jobs[js.j_firstj] == 0)
    {
      old = js.j_firstj++;
      if (old >= js.j_jobslots)
	old = js.j_jobslots - 1;
      while (js.j_firstj != old)
	{
	  if (js.j_firstj >= js.j_jobslots)
	    js.j_firstj = 0;
	  if (jobs[js.j_firstj] || js.j_firstj == old)	/* needed if old == 0 */
	    break;
	  js.j_firstj++;
	}
      if (js.j_firstj == old)
        js.j_firstj = js.j_lastj = js.j_njobs = 0;
    }
  if (jobs[js.j_lastj] == 0)
    {
      old = js.j_lastj--;
      if (old < 0)
	old = 0;
      while (js.j_lastj != old)
	{
	  if (js.j_lastj < 0)
	    js.j_lastj = js.j_jobslots - 1;
	  if (jobs[js.j_lastj] || js.j_lastj == old)	/* needed if old == js.j_jobslots */
	    break;
	  js.j_lastj--;
	}
      if (js.j_lastj == old)
        js.j_firstj = js.j_lastj = js.j_njobs = 0;
    }
}
      
/* Delete all DEAD jobs that the user had received notification about. */
static void
cleanup_dead_jobs ()
{
  register int i;
  int os;

  if (js.j_jobslots == 0 || jobs_list_frozen)
    return;

  QUEUE_SIGCHLD(os);

  /* XXX could use js.j_firstj and js.j_lastj here */
  for (i = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("cleanup_dead_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("cleanup_dead_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif

      if (jobs[i] && DEADJOB (i) && IS_NOTIFIED (i))
	delete_job (i, 0);
    }

#if defined (COPROCESS_SUPPORT)
  coproc_reap ();
#endif

  UNQUEUE_SIGCHLD(os);
}

static int
processes_in_job (job)
     int job;
{
  int nproc;
  register PROCESS *p;

  nproc = 0;
  p = jobs[job]->pipe;
  do
    {
      p = p->next;
      nproc++;
    }
  while (p != jobs[job]->pipe);

  return nproc;
}

static void
delete_old_job (pid)
     pid_t pid;
{
  PROCESS *p;
  int job;

  job = find_job (pid, 0, &p);
  if (job != NO_JOB)
    {
#ifdef DEBUG
      itrace ("delete_old_job: found pid %d in job %d with state %d", pid, job, jobs[job]->state);
#endif
      if (JOBSTATE (job) == JDEAD)
	delete_job (job, DEL_NOBGPID);
      else
	{
	  internal_warning (_("forked pid %d appears in running job %d"), pid, job);
	  if (p)
	    p->pid = 0;
	}
    }
}

/* Reallocate and compress the jobs list.  This returns with a jobs array
   whose size is a multiple of JOB_SLOTS and can hold the current number of
   jobs.  Heuristics are used to minimize the number of new reallocs. */
static void
realloc_jobs_list ()
{
  sigset_t set, oset;
  int nsize, i, j, ncur, nprev;
  JOB **nlist;

  ncur = nprev = NO_JOB;
  nsize = ((js.j_njobs + JOB_SLOTS - 1) / JOB_SLOTS);
  nsize *= JOB_SLOTS;
  i = js.j_njobs % JOB_SLOTS;
  if (i == 0 || i > (JOB_SLOTS >> 1))
    nsize += JOB_SLOTS;

  BLOCK_CHILD (set, oset);
  nlist = (js.j_jobslots == nsize) ? jobs : (JOB **) xmalloc (nsize * sizeof (JOB *));

  js.c_reaped = js.j_ndead = 0;
  for (i = j = 0; i < js.j_jobslots; i++)
    if (jobs[i])
      {
	if (i == js.j_current)
	  ncur = j;
	if (i == js.j_previous)
	  nprev = j;
	nlist[j++] = jobs[i];
	if (jobs[i]->state == JDEAD)
	  {
	    js.j_ndead++;
	    js.c_reaped += processes_in_job (i);
	  }
      }

#if defined (DEBUG)
  itrace ("realloc_jobs_list: resize jobs list from %d to %d", js.j_jobslots, nsize);
  itrace ("realloc_jobs_list: j_lastj changed from %d to %d", js.j_lastj, (j > 0) ? j - 1 : 0);
  itrace ("realloc_jobs_list: j_njobs changed from %d to %d", js.j_njobs, j);
  itrace ("realloc_jobs_list: js.j_ndead %d js.c_reaped %d", js.j_ndead, js.c_reaped);
#endif

  js.j_firstj = 0;
  js.j_lastj = (j > 0) ? j - 1 : 0;
  js.j_njobs = j;
  js.j_jobslots = nsize;

  /* Zero out remaining slots in new jobs list */
  for ( ; j < nsize; j++)
    nlist[j] = (JOB *)NULL;

  if (jobs != nlist)
    {
      free (jobs);
      jobs = nlist;
    }

  if (ncur != NO_JOB)
    js.j_current = ncur;
  if (nprev != NO_JOB)
    js.j_previous = nprev;

  /* Need to reset these */
  if (js.j_current == NO_JOB || js.j_previous == NO_JOB || js.j_current > js.j_lastj || js.j_previous > js.j_lastj)
    reset_current ();

#ifdef DEBUG
  itrace ("realloc_jobs_list: reset js.j_current (%d) and js.j_previous (%d)", js.j_current, js.j_previous);
#endif

  UNBLOCK_CHILD (oset);
}

/* Compact the jobs list by removing dead jobs.  Assumed that we have filled
   the jobs array to some predefined maximum.  Called when the shell is not
   the foreground process (subshell_environment != 0).  Returns the first
   available slot in the compacted list.  If that value is js.j_jobslots, then
   the list needs to be reallocated.  The jobs array may be in new memory if
   this returns > 0 and < js.j_jobslots.  FLAGS is reserved for future use. */
static int
compact_jobs_list (flags)
     int flags;
{
  if (js.j_jobslots == 0 || jobs_list_frozen)
    return js.j_jobslots;

  reap_dead_jobs ();
  realloc_jobs_list ();

#ifdef DEBUG
  itrace("compact_jobs_list: returning %d", (js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0);
#endif

  return ((js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0);
}

/* Delete the job at INDEX from the job list.  Must be called
   with SIGCHLD blocked. */
void
delete_job (job_index, dflags)
     int job_index, dflags;
{
  register JOB *temp;
  PROCESS *proc;
  int ndel;

  if (js.j_jobslots == 0 || jobs_list_frozen)
    return;

  if ((dflags & DEL_WARNSTOPPED) && subshell_environment == 0 && STOPPED (job_index))
    internal_warning (_("deleting stopped job %d with process group %ld"), job_index+1, (long)jobs[job_index]->pgrp);
  temp = jobs[job_index];
  if (temp == 0)
    return;

  if ((dflags & DEL_NOBGPID) == 0)
    {
      proc = find_last_proc (job_index, 0);
      /* Could do this just for J_ASYNC jobs, but we save all. */
      if (proc)
	bgp_add (proc->pid, process_exit_status (proc->status));
    }

  jobs[job_index] = (JOB *)NULL;
  if (temp == js.j_lastmade)
    js.j_lastmade = 0;
  else if (temp == js.j_lastasync)
    js.j_lastasync = 0;

  free (temp->wd);
  ndel = discard_pipeline (temp->pipe);

  js.c_injobs -= ndel;
  if (temp->state == JDEAD)
    {
      js.c_reaped -= ndel;
      js.j_ndead--;
      if (js.c_reaped < 0)
	{
#ifdef DEBUG
	  itrace("delete_job (%d pgrp %d): js.c_reaped (%d) < 0 ndel = %d js.j_ndead = %d", job_index, temp->pgrp, js.c_reaped, ndel, js.j_ndead);
#endif
	  js.c_reaped = 0;
	}
    }

  if (temp->deferred)
    dispose_command (temp->deferred);

  free (temp);

  js.j_njobs--;
  if (js.j_njobs == 0)
    js.j_firstj = js.j_lastj = 0;
  else if (jobs[js.j_firstj] == 0 || jobs[js.j_lastj] == 0)
    reset_job_indices ();

  if (job_index == js.j_current || job_index == js.j_previous)
    reset_current ();
}

/* Must be called with SIGCHLD blocked. */
void
nohup_job (job_index)
     int job_index;
{
  register JOB *temp;

  if (js.j_jobslots == 0)
    return;

  if (temp = jobs[job_index])
    temp->flags |= J_NOHUP;
}

/* Get rid of the data structure associated with a process chain. */
static int
discard_pipeline (chain)
     register PROCESS *chain;
{
  register PROCESS *this, *next;
  int n;

  this = chain;
  n = 0;
  do
    {
      next = this->next;
      FREE (this->command);
      free (this);
      n++;
      this = next;
    }
  while (this != chain);

  return n;
}

/* Add this process to the chain being built in the_pipeline.
   NAME is the command string that will be exec'ed later.
   PID is the process id of the child. */
static void
add_process (name, pid)
     char *name;
     pid_t pid;
{
  PROCESS *t, *p;

#if defined (RECYCLES_PIDS)
  int j;
  p = find_process (pid, 0, &j);
  if (p)
    {
#  ifdef DEBUG
      if (j == NO_JOB)
	internal_warning (_("add_process: process %5ld (%s) in the_pipeline"), (long)p->pid, p->command);
#  endif
      if (PALIVE (p))
        internal_warning (_("add_process: pid %5ld (%s) marked as still alive"), (long)p->pid, p->command);
      p->running = PS_RECYCLED;		/* mark as recycled */
    }
#endif

  t = (PROCESS *)xmalloc (sizeof (PROCESS));
  t->next = the_pipeline;
  t->pid = pid;
  WSTATUS (t->status) = 0;
  t->running = PS_RUNNING;
  t->command = name;
  the_pipeline = t;

  if (t->next == 0)
    t->next = t;
  else
    {
      p = t->next;
      while (p->next != t->next)
	p = p->next;
      p->next = t;
    }
}

/* Create a (dummy) PROCESS with NAME, PID, and STATUS, and make it the last
   process in jobs[JID]->pipe.  Used by the lastpipe code. */
void
append_process (name, pid, status, jid)
     char *name;
     pid_t pid;
     int status;
     int jid;
{
  PROCESS *t, *p;

  t = (PROCESS *)xmalloc (sizeof (PROCESS));
  t->next = (PROCESS *)NULL;
  t->pid = pid;
  /* set process exit status using offset discovered by configure */
  t->status = (status & 0xff) << WEXITSTATUS_OFFSET;
  t->running = PS_DONE;
  t->command = name;

  js.c_reaped++;	/* XXX */

  for (p = jobs[jid]->pipe; p->next != jobs[jid]->pipe; p = p->next)
    ;
  p->next = t;
  t->next = jobs[jid]->pipe;
}

#if 0
/* Take the last job and make it the first job.  Must be called with
   SIGCHLD blocked. */
int
rotate_the_pipeline ()
{
  PROCESS *p;

  if (the_pipeline->next == the_pipeline)
    return;
  for (p = the_pipeline; p->next != the_pipeline; p = p->next)
    ;
  the_pipeline = p;
}

/* Reverse the order of the processes in the_pipeline.  Must be called with
   SIGCHLD blocked. */
int
reverse_the_pipeline ()
{
  PROCESS *p, *n;

  if (the_pipeline->next == the_pipeline)
    return;

  for (p = the_pipeline; p->next != the_pipeline; p = p->next)
    ;
  p->next = (PROCESS *)NULL;

  n = REVERSE_LIST (the_pipeline, PROCESS *);

  the_pipeline = n;
  for (p = the_pipeline; p->next; p = p->next)
    ;
  p->next = the_pipeline;
}
#endif

/* Map FUNC over the list of jobs.  If FUNC returns non-zero,
   then it is time to stop mapping, and that is the return value
   for map_over_jobs.  FUNC is called with a JOB, arg1, arg2,
   and INDEX. */
static int
map_over_jobs (func, arg1, arg2)
     sh_job_map_func_t *func;
     int arg1, arg2;
{
  register int i;
  int result;
  sigset_t set, oset;

  if (js.j_jobslots == 0)
    return 0;

  BLOCK_CHILD (set, oset);

  /* XXX could use js.j_firstj here */
  for (i = result = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("map_over_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("map_over_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
      if (jobs[i])
	{
	  result = (*func)(jobs[i], arg1, arg2, i);
	  if (result)
	    break;
	}
    }

  UNBLOCK_CHILD (oset);

  return (result);
}

/* Cause all the jobs in the current pipeline to exit. */
void
terminate_current_pipeline ()
{
  if (pipeline_pgrp && pipeline_pgrp != shell_pgrp)
    {
      killpg (pipeline_pgrp, SIGTERM);
      killpg (pipeline_pgrp, SIGCONT);
    }
}

/* Cause all stopped jobs to exit. */
void
terminate_stopped_jobs ()
{
  register int i;

  /* XXX could use js.j_firstj here */
  for (i = 0; i < js.j_jobslots; i++)
    {
      if (jobs[i] && STOPPED (i))
	{
	  killpg (jobs[i]->pgrp, SIGTERM);
	  killpg (jobs[i]->pgrp, SIGCONT);
	}
    }
}

/* Cause all jobs, running or stopped, to receive a hangup signal.  If
   a job is marked J_NOHUP, don't send the SIGHUP. */
void
hangup_all_jobs ()
{
  register int i;

  /* XXX could use js.j_firstj here */
  for (i = 0; i < js.j_jobslots; i++)
    {
      if (jobs[i])
	{
	  if  (jobs[i]->flags & J_NOHUP)
	    continue;
	  killpg (jobs[i]->pgrp, SIGHUP);
	  if (STOPPED (i))
	    killpg (jobs[i]->pgrp, SIGCONT);
	}
    }
}

void
kill_current_pipeline ()
{
  stop_making_children ();
  start_pipeline ();
}

/* Return the pipeline that PID belongs to.  Note that the pipeline
   doesn't have to belong to a job.  Must be called with SIGCHLD blocked.
   If JOBP is non-null, return the index of the job containing PID.  */
static PROCESS *
find_pipeline (pid, alive_only, jobp)
     pid_t pid;
     int alive_only;
     int *jobp;		/* index into jobs list or NO_JOB */
{
  int job;
  PROCESS *p;

  /* See if this process is in the pipeline that we are building. */
  if (jobp)
    *jobp = NO_JOB;
  if (the_pipeline)
    {
      p = the_pipeline;
      do
	{
	  /* Return it if we found it.  Don't ever return a recycled pid. */
	  if (p->pid == pid && ((alive_only == 0 && PRECYCLED(p) == 0) || PALIVE(p)))
	    return (p);

	  p = p->next;
	}
      while (p != the_pipeline);
    }

  job = find_job (pid, alive_only, &p);
  if (jobp)
    *jobp = job;
  return (job == NO_JOB) ? (PROCESS *)NULL : jobs[job]->pipe;
}

/* Return the PROCESS * describing PID.  If JOBP is non-null return the index
   into the jobs array of the job containing PID.  Must be called with
   SIGCHLD blocked. */
static PROCESS *
find_process (pid, alive_only, jobp)
     pid_t pid;
     int alive_only;
     int *jobp;		/* index into jobs list or NO_JOB */
{
  PROCESS *p;

  p = find_pipeline (pid, alive_only, jobp);
  while (p && p->pid != pid)
    p = p->next;
  return p;
}

/* Return the job index that PID belongs to, or NO_JOB if it doesn't
   belong to any job.  Must be called with SIGCHLD blocked. */
static int
find_job (pid, alive_only, procp)
     pid_t pid;
     int alive_only;
     PROCESS **procp;
{
  register int i;
  PROCESS *p;

  /* XXX could use js.j_firstj here, and should check js.j_lastj */
  for (i = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("find_job: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("find_job: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
      if (jobs[i])
	{
	  p = jobs[i]->pipe;

	  do
	    {
	      if (p->pid == pid && ((alive_only == 0 && PRECYCLED(p) == 0) || PALIVE(p)))
		{
		  if (procp)
		    *procp = p;
		  return (i);
		}

	      p = p->next;
	    }
	  while (p != jobs[i]->pipe);
	}
    }

  return (NO_JOB);
}

/* Find a job given a PID.  If BLOCK is non-zero, block SIGCHLD as
   required by find_job. */
int
get_job_by_pid (pid, block)
     pid_t pid;
     int block;
{
  int job;
  sigset_t set, oset;

  if (block)
    BLOCK_CHILD (set, oset);

  job = find_job (pid, 0, NULL);

  if (block)
    UNBLOCK_CHILD (oset);

  return job;
}

/* Print descriptive information about the job with leader pid PID. */
void
describe_pid (pid)
     pid_t pid;
{
  int job;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);

  job = find_job (pid, 0, NULL);

  if (job != NO_JOB)
    fprintf (stderr, "[%d] %ld\n", job + 1, (long)pid);
  else
    programming_error (_("describe_pid: %ld: no such pid"), (long)pid);

  UNBLOCK_CHILD (oset);
}

static char *
j_strsignal (s)
     int s;
{
  char *x;

  x = strsignal (s);
  if (x == 0)
    {
      x = retcode_name_buffer;
      sprintf (x, _("Signal %d"), s);
    }
  return x;
}

static char *
printable_job_status (j, p, format)
     int j;
     PROCESS *p;
     int format;
{
  static char *temp;
  int es;

  temp = _("Done");

  if (STOPPED (j) && format == 0)
    {
      if (posixly_correct == 0 || p == 0 || (WIFSTOPPED (p->status) == 0))
	temp = _("Stopped");
      else
	{
	  temp = retcode_name_buffer;
	  sprintf (temp, _("Stopped(%s)"), signal_name (WSTOPSIG (p->status)));
	}
    }
  else if (RUNNING (j))
    temp = _("Running");
  else
    {
      if (WIFSTOPPED (p->status))
	temp = j_strsignal (WSTOPSIG (p->status));
      else if (WIFSIGNALED (p->status))
	temp = j_strsignal (WTERMSIG (p->status));
      else if (WIFEXITED (p->status))
	{
	  temp = retcode_name_buffer;
	  es = WEXITSTATUS (p->status);
	  if (es == 0)
	    strcpy (temp, _("Done"));
	  else if (posixly_correct)
	    sprintf (temp, _("Done(%d)"), es);
	  else
	    sprintf (temp, _("Exit %d"), es);
	}
      else
	temp = _("Unknown status");
    }

  return temp;
}

/* This is the way to print out information on a job if you
   know the index.  FORMAT is:

    JLIST_NORMAL)   [1]+ Running	   emacs
    JLIST_LONG  )   [1]+ 2378 Running      emacs
    -1	  )   [1]+ 2378	      emacs

    JLIST_NORMAL)   [1]+ Stopped	   ls | more
    JLIST_LONG  )   [1]+ 2369 Stopped      ls
			 2367	    | more
    JLIST_PID_ONLY)
	Just list the pid of the process group leader (really
	the process group).
    JLIST_CHANGED_ONLY)
	Use format JLIST_NORMAL, but list only jobs about which
	the user has not been notified. */

/* Print status for pipeline P.  If JOB_INDEX is >= 0, it is the index into
   the JOBS array corresponding to this pipeline.  FORMAT is as described
   above.  Must be called with SIGCHLD blocked.

   If you're printing a pipeline that's not in the jobs array, like the
   current pipeline as it's being created, pass -1 for JOB_INDEX */
static void
print_pipeline (p, job_index, format, stream)
     PROCESS *p;
     int job_index, format;
     FILE *stream;
{
  PROCESS *first, *last, *show;
  int es, name_padding;
  char *temp;

  if (p == 0)
    return;

  first = last = p;
  while (last->next != first)
    last = last->next;

  for (;;)
    {
      if (p != first)
	fprintf (stream, format ? "     " : " |");

      if (format != JLIST_STANDARD)
	fprintf (stream, "%5ld", (long)p->pid);

      fprintf (stream, " ");

      if (format > -1 && job_index >= 0)
	{
	  show = format ? p : last;
	  temp = printable_job_status (job_index, show, format);

	  if (p != first)
	    {
	      if (format)
		{
		  if (show->running == first->running &&
		      WSTATUS (show->status) == WSTATUS (first->status))
		    temp = "";
		}
	      else
		temp = (char *)NULL;
	    }

	  if (temp)
	    {
	      fprintf (stream, "%s", temp);

	      es = STRLEN (temp);
	      if (es == 0)
		es = 2;	/* strlen ("| ") */
	      name_padding = LONGEST_SIGNAL_DESC - es;

	      fprintf (stream, "%*s", name_padding, "");

	      if ((WIFSTOPPED (show->status) == 0) &&
		  (WIFCONTINUED (show->status) == 0) &&
		  WIFCORED (show->status))
		fprintf (stream, _("(core dumped) "));
	    }
	}

      if (p != first && format)
	fprintf (stream, "| ");

      if (p->command)
	fprintf (stream, "%s", p->command);

      if (p == last && job_index >= 0)
	{
	  temp = current_working_directory ();

	  if (RUNNING (job_index) && (IS_FOREGROUND (job_index) == 0))
	    fprintf (stream, " &");

	  if (strcmp (temp, jobs[job_index]->wd) != 0)
	    fprintf (stream,
	      _("  (wd: %s)"), polite_directory_format (jobs[job_index]->wd));
	}

      if (format || (p == last))
	{
	  /* We need to add a CR only if this is an interactive shell, and
	     we're reporting the status of a completed job asynchronously.
	     We can't really check whether this particular job is being
	     reported asynchronously, so just add the CR if the shell is
	     currently interactive and asynchronous notification is enabled. */
	  if (asynchronous_notification && interactive)
	    fprintf (stream, "\r\n");
	  else
	    fprintf (stream, "\n");
	}

      if (p == last)
	break;
      p = p->next;
    }
  fflush (stream);
}

/* Print information to STREAM about jobs[JOB_INDEX] according to FORMAT.
   Must be called with SIGCHLD blocked or queued with queue_sigchld */
static void
pretty_print_job (job_index, format, stream)
     int job_index, format;
     FILE *stream;
{
  register PROCESS *p;

  /* Format only pid information about the process group leader? */
  if (format == JLIST_PID_ONLY)
    {
      fprintf (stream, "%ld\n", (long)jobs[job_index]->pipe->pid);
      return;
    }

  if (format == JLIST_CHANGED_ONLY)
    {
      if (IS_NOTIFIED (job_index))
	return;
      format = JLIST_STANDARD;
    }

  if (format != JLIST_NONINTERACTIVE)
    fprintf (stream, "[%d]%c ", job_index + 1,
	      (job_index == js.j_current) ? '+':
		(job_index == js.j_previous) ? '-' : ' ');

  if (format == JLIST_NONINTERACTIVE)
    format = JLIST_LONG;

  p = jobs[job_index]->pipe;

  print_pipeline (p, job_index, format, stream);

  /* We have printed information about this job.  When the job's
     status changes, waitchld () sets the notification flag to 0. */
  jobs[job_index]->flags |= J_NOTIFIED;
}

static int
print_job (job, format, state, job_index)
     JOB *job;
     int format, state, job_index;
{
  if (state == -1 || (JOB_STATE)state == job->state)
    pretty_print_job (job_index, format, stdout);
  return (0);
}

void
list_one_job (job, format, ignore, job_index)
     JOB *job;
     int format, ignore, job_index;
{
  pretty_print_job (job_index, format, stdout);
}

void
list_stopped_jobs (format)
     int format;
{
  cleanup_dead_jobs ();
  map_over_jobs (print_job, format, (int)JSTOPPED);
}

void
list_running_jobs (format)
     int format;
{
  cleanup_dead_jobs ();
  map_over_jobs (print_job, format, (int)JRUNNING);
}

/* List jobs.  If FORMAT is non-zero, then the long form of the information
   is printed, else just a short version. */
void
list_all_jobs (format)
     int format;
{
  cleanup_dead_jobs ();
  map_over_jobs (print_job, format, -1);
}

/* Fork, handling errors.  Returns the pid of the newly made child, or 0.
   COMMAND is just for remembering the name of the command; we don't do
   anything else with it.  ASYNC_P says what to do with the tty.  If
   non-zero, then don't give it away. */
pid_t
make_child (command, async_p)
     char *command;
     int async_p;
{
  int forksleep;
  sigset_t set, oset;
  pid_t pid;

  sigemptyset (&set);
  sigaddset (&set, SIGCHLD);
  sigaddset (&set, SIGINT);
  sigemptyset (&oset);
  sigprocmask (SIG_BLOCK, &set, &oset);

  making_children ();

  forksleep = 1;

#if defined (BUFFERED_INPUT)
  /* If default_buffered_input is active, we are reading a script.  If
     the command is asynchronous, we have already duplicated /dev/null
     as fd 0, but have not changed the buffered stream corresponding to
     the old fd 0.  We don't want to sync the stream in this case. */
  if (default_buffered_input != -1 &&
      (!async_p || default_buffered_input > 0))
    sync_buffered_stream (default_buffered_input);
#endif /* BUFFERED_INPUT */

  /* Create the child, handle severe errors.  Retry on EAGAIN. */
  while ((pid = fork ()) < 0 && errno == EAGAIN && forksleep < FORKSLEEP_MAX)
    {
      /* bash-4.2 */
      /* If we can't create any children, try to reap some dead ones. */
      waitchld (-1, 0);

      sys_error ("fork: retry");
      if (sleep (forksleep) != 0)
	break;
      forksleep <<= 1;
    }

  if (pid < 0)
    {
      sys_error ("fork");

      /* Kill all of the processes in the current pipeline. */
      terminate_current_pipeline ();

      /* Discard the current pipeline, if any. */
      if (the_pipeline)
	kill_current_pipeline ();

      last_command_exit_value = EX_NOEXEC;
      throw_to_top_level ();	/* Reset signals, etc. */
    }

  if (pid == 0)
    {
      /* In the child.  Give this child the right process group, set the
	 signals to the default state for a new process. */
      pid_t mypid;

      mypid = getpid ();
#if defined (BUFFERED_INPUT)
      /* Close default_buffered_input if it's > 0.  We don't close it if it's
	 0 because that's the file descriptor used when redirecting input,
	 and it's wrong to close the file in that case. */
      unset_bash_input (0);
#endif /* BUFFERED_INPUT */

      /* Restore top-level signal mask. */
      sigprocmask (SIG_SETMASK, &top_level_mask, (sigset_t *)NULL);

      if (job_control)
	{
	  /* All processes in this pipeline belong in the same
	     process group. */

	  if (pipeline_pgrp == 0)	/* This is the first child. */
	    pipeline_pgrp = mypid;

	  /* Check for running command in backquotes. */
	  if (pipeline_pgrp == shell_pgrp)
	    ignore_tty_job_signals ();
	  else
	    default_tty_job_signals ();

	  /* Set the process group before trying to mess with the terminal's
	     process group.  This is mandated by POSIX. */
	  /* This is in accordance with the Posix 1003.1 standard,
	     section B.7.2.4, which says that trying to set the terminal
	     process group with tcsetpgrp() to an unused pgrp value (like
	     this would have for the first child) is an error.  Section
	     B.4.3.3, p. 237 also covers this, in the context of job control
	     shells. */
	  if (setpgid (mypid, pipeline_pgrp) < 0)
	    sys_error (_("child setpgid (%ld to %ld)"), (long)mypid, (long)pipeline_pgrp);

	  /* By convention (and assumption above), if
	     pipeline_pgrp == shell_pgrp, we are making a child for
	     command substitution.
	     In this case, we don't want to give the terminal to the
	     shell's process group (we could be in the middle of a
	     pipeline, for example). */
	  if (async_p == 0 && pipeline_pgrp != shell_pgrp && ((subshell_environment&SUBSHELL_ASYNC) == 0))
	    give_terminal_to (pipeline_pgrp, 0);

#if defined (PGRP_PIPE)
	  if (pipeline_pgrp == mypid)
	    pipe_read (pgrp_pipe);
#endif
	}
      else			/* Without job control... */
	{
	  if (pipeline_pgrp == 0)
	    pipeline_pgrp = shell_pgrp;

	  /* If these signals are set to SIG_DFL, we encounter the curious
	     situation of an interactive ^Z to a running process *working*
	     and stopping the process, but being unable to do anything with
	     that process to change its state.  On the other hand, if they
	     are set to SIG_IGN, jobs started from scripts do not stop when
	     the shell running the script gets a SIGTSTP and stops. */

	  default_tty_job_signals ();
	}

#if defined (PGRP_PIPE)
      /* Release the process group pipe, since our call to setpgid ()
	 is done.  The last call to sh_closepipe is done in stop_pipeline. */
      sh_closepipe (pgrp_pipe);
#endif /* PGRP_PIPE */

#if 0
      /* Don't set last_asynchronous_pid in the child */
      if (async_p)
	last_asynchronous_pid = mypid;		/* XXX */
      else
#endif
#if defined (RECYCLES_PIDS)
      if (last_asynchronous_pid == mypid)
        /* Avoid pid aliasing.  1 seems like a safe, unusual pid value. */
	last_asynchronous_pid = 1;
#endif
    }
  else
    {
      /* In the parent.  Remember the pid of the child just created
	 as the proper pgrp if this is the first child. */

      if (first_pid == NO_PID)
	first_pid = pid;
      else if (pid_wrap == -1 && pid < first_pid)
	pid_wrap = 0;
      else if (pid_wrap == 0 && pid >= first_pid)
	pid_wrap = 1;

      if (job_control)
	{
	  if (pipeline_pgrp == 0)
	    {
	      pipeline_pgrp = pid;
	      /* Don't twiddle terminal pgrps in the parent!  This is the bug,
		 not the good thing of twiddling them in the child! */
	      /* give_terminal_to (pipeline_pgrp, 0); */
	    }
	  /* This is done on the recommendation of the Rationale section of
	     the POSIX 1003.1 standard, where it discusses job control and
	     shells.  It is done to avoid possible race conditions. (Ref.
	     1003.1 Rationale, section B.4.3.3, page 236). */
	  setpgid (pid, pipeline_pgrp);
	}
      else
	{
	  if (pipeline_pgrp == 0)
	    pipeline_pgrp = shell_pgrp;
	}

      /* Place all processes into the jobs array regardless of the
	 state of job_control. */
      add_process (command, pid);

      if (async_p)
	last_asynchronous_pid = pid;
#if defined (RECYCLES_PIDS)
      else if (last_asynchronous_pid == pid)
        /* Avoid pid aliasing.  1 seems like a safe, unusual pid value. */
	last_asynchronous_pid = 1;
#endif

      if (pid_wrap > 0)
	delete_old_job (pid);

#if !defined (RECYCLES_PIDS)
      /* Only check for saved status if we've saved more than CHILD_MAX
	 statuses, unless the system recycles pids. */
      if ((js.c_reaped + bgpids.npid) >= js.c_childmax)
#endif
	bgp_delete (pid);		/* new process, discard any saved status */

      last_made_pid = pid;

      /* keep stats */
      js.c_totforked++;
      js.c_living++;

      /* Unblock SIGINT and SIGCHLD unless creating a pipeline, in which case
	 SIGCHLD remains blocked until all commands in the pipeline have been
	 created. */
      sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL);
    }

  return (pid);
}

/* These two functions are called only in child processes. */
void
ignore_tty_job_signals ()
{
  set_signal_handler (SIGTSTP, SIG_IGN);
  set_signal_handler (SIGTTIN, SIG_IGN);
  set_signal_handler (SIGTTOU, SIG_IGN);
}

void
default_tty_job_signals ()
{
  set_signal_handler (SIGTSTP, SIG_DFL);
  set_signal_handler (SIGTTIN, SIG_DFL);
  set_signal_handler (SIGTTOU, SIG_DFL);
}

/* When we end a job abnormally, or if we stop a job, we set the tty to the
   state kept in here.  When a job ends normally, we set the state in here
   to the state of the tty. */

static TTYSTRUCT shell_tty_info;

#if defined (NEW_TTY_DRIVER)
static struct tchars shell_tchars;
static struct ltchars shell_ltchars;
#endif /* NEW_TTY_DRIVER */

#if defined (NEW_TTY_DRIVER) && defined (DRAIN_OUTPUT)
/* Since the BSD tty driver does not allow us to change the tty modes
   while simultaneously waiting for output to drain and preserving
   typeahead, we have to drain the output ourselves before calling
   ioctl.  We cheat by finding the length of the output queue, and
   using select to wait for an appropriate length of time.  This is
   a hack, and should be labeled as such (it's a hastily-adapted
   mutation of a `usleep' implementation).  It's only reason for
   existing is the flaw in the BSD tty driver. */

static int ttspeeds[] =
{
  0, 50, 75, 110, 134, 150, 200, 300, 600, 1200,
  1800, 2400, 4800, 9600, 19200, 38400
};

static void
draino (fd, ospeed)
     int fd, ospeed;
{
  register int delay = ttspeeds[ospeed];
  int n;

  if (!delay)
    return;

  while ((ioctl (fd, TIOCOUTQ, &n) == 0) && n)
    {
      if (n > (delay / 100))
	{
	  struct timeval tv;

	  n *= 10;		/* 2 bits more for conservativeness. */
	  tv.tv_sec = n / delay;
	  tv.tv_usec = ((n % delay) * 1000000) / delay;
	  select (fd, (fd_set *)0, (fd_set *)0, (fd_set *)0, &tv);
	}
      else
	break;
    }
}
#endif /* NEW_TTY_DRIVER && DRAIN_OUTPUT */

/* Return the fd from which we are actually getting input. */
#define input_tty() (shell_tty != -1) ? shell_tty : fileno (stderr)

/* Fill the contents of shell_tty_info with the current tty info. */
int
get_tty_state ()
{
  int tty;

  tty = input_tty ();
  if (tty != -1)
    {
#if defined (NEW_TTY_DRIVER)
      ioctl (tty, TIOCGETP, &shell_tty_info);
      ioctl (tty, TIOCGETC, &shell_tchars);
      ioctl (tty, TIOCGLTC, &shell_ltchars);
#endif /* NEW_TTY_DRIVER */

#if defined (TERMIO_TTY_DRIVER)
      ioctl (tty, TCGETA, &shell_tty_info);
#endif /* TERMIO_TTY_DRIVER */

#if defined (TERMIOS_TTY_DRIVER)
      if (tcgetattr (tty, &shell_tty_info) < 0)
	{
#if 0
	  /* Only print an error message if we're really interactive at
	     this time. */
	  if (interactive)
	    sys_error ("[%ld: %d (%d)] tcgetattr", (long)getpid (), shell_level, tty);
#endif
	  return -1;
	}
#endif /* TERMIOS_TTY_DRIVER */
      if (check_window_size)
	get_new_window_size (0, (int *)0, (int *)0);
    }
  return 0;
}

/* Make the current tty use the state in shell_tty_info. */
int
set_tty_state ()
{
  int tty;

  tty = input_tty ();
  if (tty != -1)
    {
#if defined (NEW_TTY_DRIVER)
#  if defined (DRAIN_OUTPUT)
      draino (tty, shell_tty_info.sg_ospeed);
#  endif /* DRAIN_OUTPUT */
      ioctl (tty, TIOCSETN, &shell_tty_info);
      ioctl (tty, TIOCSETC, &shell_tchars);
      ioctl (tty, TIOCSLTC, &shell_ltchars);
#endif /* NEW_TTY_DRIVER */

#if defined (TERMIO_TTY_DRIVER)
      ioctl (tty, TCSETAW, &shell_tty_info);
#endif /* TERMIO_TTY_DRIVER */

#if defined (TERMIOS_TTY_DRIVER)
      if (tcsetattr (tty, TCSADRAIN, &shell_tty_info) < 0)
	{
	  /* Only print an error message if we're really interactive at
	     this time. */
	  if (interactive)
	    sys_error ("[%ld: %d (%d)] tcsetattr", (long)getpid (), shell_level, tty);
	  return -1;
	}
#endif /* TERMIOS_TTY_DRIVER */
    }
  return 0;
}

/* Given an index into the jobs array JOB, return the PROCESS struct of the last
   process in that job's pipeline.  This is the one whose exit status
   counts.  Must be called with SIGCHLD blocked or queued. */
static PROCESS *
find_last_proc (job, block)
     int job;
     int block;
{
  register PROCESS *p;
  sigset_t set, oset;

  if (block)
    BLOCK_CHILD (set, oset);

  p = jobs[job]->pipe;
  while (p && p->next != jobs[job]->pipe)
    p = p->next;

  if (block)
    UNBLOCK_CHILD (oset);

  return (p);
}

static pid_t
find_last_pid (job, block)
     int job;
     int block;
{
  PROCESS *p;

  p = find_last_proc (job, block);
  /* Possible race condition here. */
  return p->pid;
}     

/* Wait for a particular child of the shell to finish executing.
   This low-level function prints an error message if PID is not
   a child of this shell.  It returns -1 if it fails, or whatever
   wait_for returns otherwise.  If the child is not found in the
   jobs table, it returns 127. */
int
wait_for_single_pid (pid)
     pid_t pid;
{
  register PROCESS *child;
  sigset_t set, oset;
  int r, job;

  BLOCK_CHILD (set, oset);
  child = find_pipeline (pid, 0, (int *)NULL);
  UNBLOCK_CHILD (oset);

  if (child == 0)
    {
      r = bgp_search (pid);
      if (r >= 0)
	return r;
    }

  if (child == 0)
    {
      internal_error (_("wait: pid %ld is not a child of this shell"), (long)pid);
      return (127);
    }

  r = wait_for (pid);

  /* POSIX.2: if we just waited for a job, we can remove it from the jobs
     table. */
  BLOCK_CHILD (set, oset);
  job = find_job (pid, 0, NULL);
  if (job != NO_JOB && jobs[job] && DEADJOB (job))
    jobs[job]->flags |= J_NOTIFIED;
  UNBLOCK_CHILD (oset);

  /* If running in posix mode, remove the job from the jobs table immediately */
  if (posixly_correct)
    {
      cleanup_dead_jobs ();
      bgp_delete (pid);
    }

  return r;
}

/* Wait for all of the background processes started by this shell to finish. */
void
wait_for_background_pids ()
{
  register int i, r, waited_for;
  sigset_t set, oset;
  pid_t pid;

  for (waited_for = 0;;)
    {
      BLOCK_CHILD (set, oset);

      /* find first running job; if none running in foreground, break */
      /* XXX could use js.j_firstj and js.j_lastj here */
      for (i = 0; i < js.j_jobslots; i++)
	{
#if defined (DEBUG)
	  if (i < js.j_firstj && jobs[i])
	    itrace("wait_for_background_pids: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
	  if (i > js.j_lastj && jobs[i])
	    itrace("wait_for_background_pids: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
	  if (jobs[i] && RUNNING (i) && IS_FOREGROUND (i) == 0)
	    break;
	}
      if (i == js.j_jobslots)
	{
	  UNBLOCK_CHILD (oset);
	  break;
	}

      /* now wait for the last pid in that job. */
      pid = find_last_pid (i, 0);
      UNBLOCK_CHILD (oset);
      QUIT;
      errno = 0;		/* XXX */
      r = wait_for_single_pid (pid);
      if (r == -1)
	{
	  /* If we're mistaken about job state, compensate. */
	  if (errno == ECHILD)
	    mark_all_jobs_as_dead ();
	}
      else
	waited_for++;
    }

  /* POSIX.2 says the shell can discard the statuses of all completed jobs if
     `wait' is called with no arguments. */
  mark_dead_jobs_as_notified (1);
  cleanup_dead_jobs ();
  bgp_clear ();
}

/* Make OLD_SIGINT_HANDLER the SIGINT signal handler. */
#define INVALID_SIGNAL_HANDLER (SigHandler *)wait_for_background_pids
static SigHandler *old_sigint_handler = INVALID_SIGNAL_HANDLER;

static void
restore_sigint_handler ()
{
  if (old_sigint_handler != INVALID_SIGNAL_HANDLER)
    {
      set_signal_handler (SIGINT, old_sigint_handler);
      old_sigint_handler = INVALID_SIGNAL_HANDLER;
    }
}

static int wait_sigint_received;

/* Handle SIGINT while we are waiting for children in a script to exit.
   The `wait' builtin should be interruptible, but all others should be
   effectively ignored (i.e. not cause the shell to exit). */
static sighandler
wait_sigint_handler (sig)
     int sig;
{
  SigHandler *sigint_handler;

  if (interrupt_immediately ||
      (this_shell_builtin && this_shell_builtin == wait_builtin))
    {
      last_command_exit_value = EXECUTION_FAILURE;
      restore_sigint_handler ();
      /* If we got a SIGINT while in `wait', and SIGINT is trapped, do
	 what POSIX.2 says (see builtins/wait.def for more info). */
      if (this_shell_builtin && this_shell_builtin == wait_builtin &&
	  signal_is_trapped (SIGINT) &&
	  ((sigint_handler = trap_to_sighandler (SIGINT)) == trap_handler))
	{
	  interrupt_immediately = 0;
	  trap_handler (SIGINT);	/* set pending_traps[SIGINT] */
	  wait_signal_received = SIGINT;
	  longjmp (wait_intr_buf, 1);
	}
      
      ADDINTERRUPT;
      QUIT;
    }

  /* XXX - should this be interrupt_state?  If it is, the shell will act
     as if it got the SIGINT interrupt. */
  wait_sigint_received = 1;

  /* Otherwise effectively ignore the SIGINT and allow the running job to
     be killed. */
  SIGRETURN (0);
}

static int
process_exit_signal (status)
     WAIT status;
{
  return (WIFSIGNALED (status) ? WTERMSIG (status) : 0);
}

static int
process_exit_status (status)
     WAIT status;
{
  if (WIFSIGNALED (status))
    return (128 + WTERMSIG (status));
  else if (WIFSTOPPED (status) == 0)
    return (WEXITSTATUS (status));
  else
    return (EXECUTION_SUCCESS);
}

static WAIT
job_signal_status (job)
     int job;
{
  register PROCESS *p;
  WAIT s;

  p = jobs[job]->pipe;
  do
    {
      s = p->status;
      if (WIFSIGNALED(s) || WIFSTOPPED(s))
	break;
      p = p->next;
    }
  while (p != jobs[job]->pipe);

  return s;
}
  
/* Return the exit status of the last process in the pipeline for job JOB.
   This is the exit status of the entire job. */
static WAIT
raw_job_exit_status (job)
     int job;
{
  register PROCESS *p;
  int fail;
  WAIT ret;

  if (pipefail_opt)
    {
      fail = 0;
      p = jobs[job]->pipe;
      do
	{
	  if (WSTATUS (p->status) != EXECUTION_SUCCESS)
	    fail = WSTATUS(p->status);
	  p = p->next;
	}
      while (p != jobs[job]->pipe);
      WSTATUS (ret) = fail;
      return ret;
    }

  for (p = jobs[job]->pipe; p->next != jobs[job]->pipe; p = p->next)
    ;
  return (p->status);
}

/* Return the exit status of job JOB.  This is the exit status of the last
   (rightmost) process in the job's pipeline, modified if the job was killed
   by a signal or stopped. */
int
job_exit_status (job)
     int job;
{
  return (process_exit_status (raw_job_exit_status (job)));
}

int
job_exit_signal (job)
     int job;
{
  return (process_exit_signal (raw_job_exit_status (job)));
}

#define FIND_CHILD(pid, child) \
  do \
    { \
      child = find_pipeline (pid, 0, (int *)NULL); \
      if (child == 0) \
	{ \
	  give_terminal_to (shell_pgrp, 0); \
	  UNBLOCK_CHILD (oset); \
	  internal_error (_("wait_for: No record of process %ld"), (long)pid); \
	  restore_sigint_handler (); \
	  return (termination_state = 127); \
	} \
    } \
  while (0)

/* Wait for pid (one of our children) to terminate, then
   return the termination state.  Returns 127 if PID is not found in
   the jobs table.  Returns -1 if waitchld() returns -1, indicating
   that there are no unwaited-for child processes. */
int
wait_for (pid)
     pid_t pid;
{
  int job, termination_state, r;
  WAIT s;
  register PROCESS *child;
  sigset_t set, oset;

  /* In the case that this code is interrupted, and we longjmp () out of it,
     we are relying on the code in throw_to_top_level () to restore the
     top-level signal mask. */
  BLOCK_CHILD (set, oset);

  /* Ignore interrupts while waiting for a job run without job control
     to finish.  We don't want the shell to exit if an interrupt is
     received, only if one of the jobs run is killed via SIGINT.  If
     job control is not set, the job will be run in the same pgrp as
     the shell, and the shell will see any signals the job gets.  In
     fact, we want this set every time the waiting shell and the waited-
     for process are in the same process group, including command
     substitution. */

  /* This is possibly a race condition -- should it go in stop_pipeline? */
  wait_sigint_received = 0;
  if (job_control == 0 || (subshell_environment&SUBSHELL_COMSUB))
    {
      old_sigint_handler = set_signal_handler (SIGINT, wait_sigint_handler);
      if (old_sigint_handler == SIG_IGN)
	set_signal_handler (SIGINT, old_sigint_handler);
    }

  termination_state = last_command_exit_value;

  if (interactive && job_control == 0)
    QUIT;
  /* Check for terminating signals and exit the shell if we receive one */
  CHECK_TERMSIG;

  /* If we say wait_for (), then we have a record of this child somewhere.
     If it and none of its peers are running, don't call waitchld(). */

  job = NO_JOB;
  do
    {
      FIND_CHILD (pid, child);

      /* If this child is part of a job, then we are really waiting for the
	 job to finish.  Otherwise, we are waiting for the child to finish.
	 We check for JDEAD in case the job state has been set by waitchld
	 after receipt of a SIGCHLD. */
      if (job == NO_JOB)
	job = find_job (pid, 0, NULL);

      /* waitchld() takes care of setting the state of the job.  If the job
	 has already exited before this is called, sigchld_handler will have
	 called waitchld and the state will be set to JDEAD. */

      if (PRUNNING(child) || (job != NO_JOB && RUNNING (job)))
	{
#if defined (WAITPID_BROKEN)    /* SCOv4 */
	  sigset_t suspend_set;
	  sigemptyset (&suspend_set);
	  sigsuspend (&suspend_set);
#else /* !WAITPID_BROKEN */
#  if defined (MUST_UNBLOCK_CHLD)
	  struct sigaction act, oact;
	  sigset_t nullset, chldset;

	  sigemptyset (&nullset);
	  sigemptyset (&chldset);
	  sigprocmask (SIG_SETMASK, &nullset, &chldset);
	  act.sa_handler = SIG_DFL;
	  sigemptyset (&act.sa_mask);
	  sigemptyset (&oact.sa_mask);
	  act.sa_flags = 0;
	  sigaction (SIGCHLD, &act, &oact);
#  endif
	  queue_sigchld = 1;
	  r = waitchld (pid, 1);
#  if defined (MUST_UNBLOCK_CHLD)
	  sigaction (SIGCHLD, &oact, (struct sigaction *)NULL);
	  sigprocmask (SIG_SETMASK, &chldset, (sigset_t *)NULL);
#  endif
	  queue_sigchld = 0;
	  if (r == -1 && errno == ECHILD && this_shell_builtin == wait_builtin)
	    {
	      termination_state = -1;
	      goto wait_for_return;
	    }

	  /* If child is marked as running, but waitpid() returns -1/ECHILD,
	     there is something wrong.  Somewhere, wait should have returned
	     that child's pid.  Mark the child as not running and the job,
	     if it exists, as JDEAD. */
	  if (r == -1 && errno == ECHILD)
	    {
	      child->running = PS_DONE;
	      WSTATUS (child->status) = 0;	/* XXX -- can't find true status */
	      js.c_living = 0;		/* no living child processes */
	      if (job != NO_JOB)
		{
		  jobs[job]->state = JDEAD;
		  js.c_reaped++;
		  js.j_ndead++;
		}
	    }
#endif /* WAITPID_BROKEN */
	}

      /* If the shell is interactive, and job control is disabled, see
	 if the foreground process has died due to SIGINT and jump out
	 of the wait loop if it has.  waitchld has already restored the
	 old SIGINT signal handler. */
      if (interactive && job_control == 0)
	QUIT;
      /* Check for terminating signals and exit the shell if we receive one */
      CHECK_TERMSIG;
    }
  while (PRUNNING (child) || (job != NO_JOB && RUNNING (job)));

  /* The exit state of the command is either the termination state of the
     child, or the termination state of the job.  If a job, the status
     of the last child in the pipeline is the significant one.  If the command
     or job was terminated by a signal, note that value also. */
  termination_state = (job != NO_JOB) ? job_exit_status (job)
				      : process_exit_status (child->status);
  last_command_exit_signal = (job != NO_JOB) ? job_exit_signal (job)
					     : process_exit_signal (child->status);

  /* XXX */
  if ((job != NO_JOB && JOBSTATE (job) == JSTOPPED) || WIFSTOPPED (child->status))
    termination_state = 128 + WSTOPSIG (child->status);

  if (job == NO_JOB || IS_JOBCONTROL (job))
    {
      /* XXX - under what circumstances is a job not present in the jobs
	 table (job == NO_JOB)?
	 	1.  command substitution

	 In the case of command substitution, at least, it's probably not
	 the right thing to give the terminal to the shell's process group,
	 even though there is code in subst.c:command_substitute to work
	 around it.

	 Things that don't:
		$PROMPT_COMMAND execution
		process substitution
       */
#if 0
if (job == NO_JOB)
  itrace("wait_for: job == NO_JOB, giving the terminal to shell_pgrp (%ld)", (long)shell_pgrp);
#endif
      give_terminal_to (shell_pgrp, 0);
    }

  /* If the command did not exit cleanly, or the job is just
     being stopped, then reset the tty state back to what it
     was before this command.  Reset the tty state and notify
     the user of the job termination only if the shell is
     interactive.  Clean up any dead jobs in either case. */
  if (job != NO_JOB)
    {
      if (interactive_shell && subshell_environment == 0)
	{
	  /* This used to use `child->status'.  That's wrong, however, for
	     pipelines.  `child' is the first process in the pipeline.  It's
	     likely that the process we want to check for abnormal termination
	     or stopping is the last process in the pipeline, especially if
	     it's long-lived and the first process is short-lived.  Since we
	     know we have a job here, we can check all the processes in this
	     job's pipeline and see if one of them stopped or terminated due
	     to a signal.  We might want to change this later to just check
	     the last process in the pipeline.  If no process exits due to a
	     signal, S is left as the status of the last job in the pipeline. */
	  s = job_signal_status (job);

	  if (WIFSIGNALED (s) || WIFSTOPPED (s))
	    {
	      set_tty_state ();

	      /* If the current job was stopped or killed by a signal, and
		 the user has requested it, get a possibly new window size */
	      if (check_window_size && (job == js.j_current || IS_FOREGROUND (job)))
		get_new_window_size (0, (int *)0, (int *)0);
	    }
	  else
	    get_tty_state ();

	  /* If job control is enabled, the job was started with job
	     control, the job was the foreground job, and it was killed
	     by SIGINT, then print a newline to compensate for the kernel
	     printing the ^C without a trailing newline. */
	  if (job_control && IS_JOBCONTROL (job) && IS_FOREGROUND (job) &&
		WIFSIGNALED (s) && WTERMSIG (s) == SIGINT)
	    {
	      /* If SIGINT is not trapped and the shell is in a for, while,
		 or until loop, act as if the shell received SIGINT as
		 well, so the loop can be broken.  This doesn't call the
		 SIGINT signal handler; maybe it should. */
	      if (signal_is_trapped (SIGINT) == 0 && (loop_level || (shell_compatibility_level > 32 && executing_list)))
		ADDINTERRUPT;
	      else
		{
		  putchar ('\n');
		  fflush (stdout);
		}
	    }
	}
      else if ((subshell_environment & (SUBSHELL_COMSUB|SUBSHELL_PIPE)) && wait_sigint_received)
	{
	  /* If waiting for a job in a subshell started to do command
	     substitution or to run a pipeline element that consists of
	     something like a while loop or a for loop, simulate getting
	     and being killed by the SIGINT to pass the status back to our
	     parent. */
	  s = job_signal_status (job);
	
	  if (WIFSIGNALED (s) && WTERMSIG (s) == SIGINT && signal_is_trapped (SIGINT) == 0)
	    {
	      UNBLOCK_CHILD (oset);
	      restore_sigint_handler ();
	      old_sigint_handler = set_signal_handler (SIGINT, SIG_DFL);
	      if (old_sigint_handler == SIG_IGN)
		restore_sigint_handler ();
	      else
		kill (getpid (), SIGINT);
	    }
	}

      /* Moved here from set_job_status_and_cleanup, which is in the SIGCHLD
         signal handler path */
      if (DEADJOB (job) && IS_FOREGROUND (job) /*&& subshell_environment == 0*/)
	setjstatus (job);

      /* If this job is dead, notify the user of the status.  If the shell
	 is interactive, this will display a message on the terminal.  If
	 the shell is not interactive, make sure we turn on the notify bit
	 so we don't get an unwanted message about the job's termination,
	 and so delete_job really clears the slot in the jobs table. */
      notify_and_cleanup ();
    }

wait_for_return:

  UNBLOCK_CHILD (oset);

  /* Restore the original SIGINT signal handler before we return. */
  restore_sigint_handler ();

  return (termination_state);
}

/* Wait for the last process in the pipeline for JOB.  Returns whatever
   wait_for returns: the last process's termination state or -1 if there
   are no unwaited-for child processes or an error occurs. */
int
wait_for_job (job)
     int job;
{
  pid_t pid;
  int r;
  sigset_t set, oset;

  BLOCK_CHILD(set, oset);
  if (JOBSTATE (job) == JSTOPPED)
    internal_warning (_("wait_for_job: job %d is stopped"), job+1);

  pid = find_last_pid (job, 0);
  UNBLOCK_CHILD(oset);
  r = wait_for (pid);

  /* POSIX.2: we can remove the job from the jobs table if we just waited
     for it. */
  BLOCK_CHILD (set, oset);
  if (job != NO_JOB && jobs[job] && DEADJOB (job))
    jobs[job]->flags |= J_NOTIFIED;
  UNBLOCK_CHILD (oset);

  return r;
}

/* Print info about dead jobs, and then delete them from the list
   of known jobs.  This does not actually delete jobs when the
   shell is not interactive, because the dead jobs are not marked
   as notified. */
void
notify_and_cleanup ()
{
  if (jobs_list_frozen)
    return;

  if (interactive || interactive_shell == 0 || sourcelevel)
    notify_of_job_status ();

  cleanup_dead_jobs ();
}

/* Make dead jobs disappear from the jobs array without notification.
   This is used when the shell is not interactive. */
void
reap_dead_jobs ()
{
  mark_dead_jobs_as_notified (0);
  cleanup_dead_jobs ();
}

/* Return the next closest (chronologically) job to JOB which is in
   STATE.  STATE can be JSTOPPED, JRUNNING.  NO_JOB is returned if
   there is no next recent job. */
static int
most_recent_job_in_state (job, state)
     int job;
     JOB_STATE state;
{
  register int i, result;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);

  for (result = NO_JOB, i = job - 1; i >= 0; i--)
    {
      if (jobs[i] && (JOBSTATE (i) == state))
	{
	  result = i;
	  break;
	}
    }

  UNBLOCK_CHILD (oset);

  return (result);
}

/* Return the newest *stopped* job older than JOB, or NO_JOB if not
   found. */
static int
job_last_stopped (job)
     int job;
{
  return (most_recent_job_in_state (job, JSTOPPED));
}

/* Return the newest *running* job older than JOB, or NO_JOB if not
   found. */
static int
job_last_running (job)
     int job;
{
  return (most_recent_job_in_state (job, JRUNNING));
}

/* Make JOB be the current job, and make previous be useful.  Must be
   called with SIGCHLD blocked. */
static void
set_current_job (job)
     int job;
{
  int candidate;

  if (js.j_current != job)
    {
      js.j_previous = js.j_current;
      js.j_current = job;
    }

  /* First choice for previous job is the old current job. */
  if (js.j_previous != js.j_current &&
      js.j_previous != NO_JOB &&
      jobs[js.j_previous] &&
      STOPPED (js.j_previous))
    return;

  /* Second choice:  Newest stopped job that is older than
     the current job. */
  candidate = NO_JOB;
  if (STOPPED (js.j_current))
    {
      candidate = job_last_stopped (js.j_current);

      if (candidate != NO_JOB)
	{
	  js.j_previous = candidate;
	  return;
	}
    }

  /* If we get here, there is either only one stopped job, in which case it is
     the current job and the previous job should be set to the newest running
     job, or there are only running jobs and the previous job should be set to
     the newest running job older than the current job.  We decide on which
     alternative to use based on whether or not JOBSTATE(js.j_current) is
     JSTOPPED. */

  candidate = RUNNING (js.j_current) ? job_last_running (js.j_current)
				    : job_last_running (js.j_jobslots);

  if (candidate != NO_JOB)
    {
      js.j_previous = candidate;
      return;
    }

  /* There is only a single job, and it is both `+' and `-'. */
  js.j_previous = js.j_current;
}

/* Make current_job be something useful, if it isn't already. */

/* Here's the deal:  The newest non-running job should be `+', and the
   next-newest non-running job should be `-'.  If there is only a single
   stopped job, the js.j_previous is the newest non-running job.  If there
   are only running jobs, the newest running job is `+' and the
   next-newest running job is `-'.  Must be called with SIGCHLD blocked. */

static void
reset_current ()
{
  int candidate;

  if (js.j_jobslots && js.j_current != NO_JOB && jobs[js.j_current] && STOPPED (js.j_current))
    candidate = js.j_current;
  else
    {
      candidate = NO_JOB;

      /* First choice: the previous job. */
      if (js.j_previous != NO_JOB && jobs[js.j_previous] && STOPPED (js.j_previous))
	candidate = js.j_previous;

      /* Second choice: the most recently stopped job. */
      if (candidate == NO_JOB)
	candidate = job_last_stopped (js.j_jobslots);

      /* Third choice: the newest running job. */
      if (candidate == NO_JOB)
	candidate = job_last_running (js.j_jobslots);
    }

  /* If we found a job to use, then use it.  Otherwise, there
     are no jobs period. */
  if (candidate != NO_JOB)
    set_current_job (candidate);
  else
    js.j_current = js.j_previous = NO_JOB;
}

/* Set up the job structures so we know the job and its processes are
   all running. */
static void
set_job_running (job)
     int job;
{
  register PROCESS *p;

  /* Each member of the pipeline is now running. */
  p = jobs[job]->pipe;

  do
    {
      if (WIFSTOPPED (p->status))
	p->running = PS_RUNNING;	/* XXX - could be PS_STOPPED */
      p = p->next;
    }
  while (p != jobs[job]->pipe);

  /* This means that the job is running. */
  JOBSTATE (job) = JRUNNING;
}

/* Start a job.  FOREGROUND if non-zero says to do that.  Otherwise,
   start the job in the background.  JOB is a zero-based index into
   JOBS.  Returns -1 if it is unable to start a job, and the return
   status of the job otherwise. */
int
start_job (job, foreground)
     int job, foreground;
{
  register PROCESS *p;
  int already_running;
  sigset_t set, oset;
  char *wd, *s;
  static TTYSTRUCT save_stty;

  BLOCK_CHILD (set, oset);

  if (DEADJOB (job))
    {
      internal_error (_("%s: job has terminated"), this_command_name);
      UNBLOCK_CHILD (oset);
      return (-1);
    }

  already_running = RUNNING (job);

  if (foreground == 0 && already_running)
    {
      internal_error (_("%s: job %d already in background"), this_command_name, job + 1);
      UNBLOCK_CHILD (oset);
      return (0);		/* XPG6/SUSv3 says this is not an error */
    }

  wd = current_working_directory ();

  /* You don't know about the state of this job.  Do you? */
  jobs[job]->flags &= ~J_NOTIFIED;

  if (foreground)
    {
      set_current_job (job);
      jobs[job]->flags |= J_FOREGROUND;
    }

  /* Tell the outside world what we're doing. */
  p = jobs[job]->pipe;

  if (foreground == 0)
    {
      /* POSIX.2 says `bg' doesn't give any indication about current or
	 previous job. */
      if (posixly_correct == 0)
	s = (job == js.j_current) ? "+ ": ((job == js.j_previous) ? "- " : " ");       
      else
	s = " ";
      printf ("[%d]%s", job + 1, s);
    }

  do
    {
      printf ("%s%s",
	       p->command ? p->command : "",
	       p->next != jobs[job]->pipe? " | " : "");
      p = p->next;
    }
  while (p != jobs[job]->pipe);

  if (foreground == 0)
    printf (" &");

  if (strcmp (wd, jobs[job]->wd) != 0)
    printf ("	(wd: %s)", polite_directory_format (jobs[job]->wd));

  printf ("\n");

  /* Run the job. */
  if (already_running == 0)
    set_job_running (job);

  /* Save the tty settings before we start the job in the foreground. */
  if (foreground)
    {
      get_tty_state ();
      save_stty = shell_tty_info;
      /* Give the terminal to this job. */
      if (IS_JOBCONTROL (job))
	give_terminal_to (jobs[job]->pgrp, 0);
    }
  else
    jobs[job]->flags &= ~J_FOREGROUND;

  /* If the job is already running, then don't bother jump-starting it. */
  if (already_running == 0)
    {
      jobs[job]->flags |= J_NOTIFIED;
      killpg (jobs[job]->pgrp, SIGCONT);
    }

  if (foreground)
    {
      pid_t pid;
      int st;

      pid = find_last_pid (job, 0);
      UNBLOCK_CHILD (oset);
      st = wait_for (pid);
      shell_tty_info = save_stty;
      set_tty_state ();
      return (st);
    }
  else
    {
      reset_current ();
      UNBLOCK_CHILD (oset);
      return (0);
    }
}

/* Give PID SIGNAL.  This determines what job the pid belongs to (if any).
   If PID does belong to a job, and the job is stopped, then CONTinue the
   job after giving it SIGNAL.  Returns -1 on failure.  If GROUP is non-null,
   then kill the process group associated with PID. */
int
kill_pid (pid, sig, group)
     pid_t pid;
     int sig, group;
{
  register PROCESS *p;
  int job, result, negative;
  sigset_t set, oset;

  if (pid < -1)
    {
      pid = -pid;
      group = negative = 1;
    }
  else
    negative = 0;

  result = EXECUTION_SUCCESS;
  if (group)
    {
      BLOCK_CHILD (set, oset);
      p = find_pipeline (pid, 0, &job);

      if (job != NO_JOB)
	{
	  jobs[job]->flags &= ~J_NOTIFIED;

	  /* Kill process in backquotes or one started without job control? */

	  /* If we're passed a pid < -1, just call killpg and see what happens  */
	  if (negative && jobs[job]->pgrp == shell_pgrp)
	    result = killpg (pid, sig);
	  /* If we're killing using job control notification, for example,
	     without job control active, we have to do things ourselves. */
	  else if (jobs[job]->pgrp == shell_pgrp)
	    {
	      p = jobs[job]->pipe;
	      do
		{
		  if (PALIVE (p) == 0)
		    continue;		/* avoid pid recycling problem */
		  kill (p->pid, sig);
		  if (PEXITED (p) && (sig == SIGTERM || sig == SIGHUP))
		    kill (p->pid, SIGCONT);
		  p = p->next;
		}
	      while  (p != jobs[job]->pipe);
	    }
	  else
	    {
	      result = killpg (jobs[job]->pgrp, sig);
	      if (p && STOPPED (job) && (sig == SIGTERM || sig == SIGHUP))
		killpg (jobs[job]->pgrp, SIGCONT);
	      /* If we're continuing a stopped job via kill rather than bg or
		 fg, emulate the `bg' behavior. */
	      if (p && STOPPED (job) && (sig == SIGCONT))
		{
		  set_job_running (job);
		  jobs[job]->flags &= ~J_FOREGROUND;
		  jobs[job]->flags |= J_NOTIFIED;
		}
	    }
	}
      else
	result = killpg (pid, sig);

      UNBLOCK_CHILD (oset);
    }
  else
    result = kill (pid, sig);

  return (result);
}

/* sigchld_handler () flushes at least one of the children that we are
   waiting for.  It gets run when we have gotten a SIGCHLD signal. */
static sighandler
sigchld_handler (sig)
     int sig;
{
  int n, oerrno;

  oerrno = errno;
  REINSTALL_SIGCHLD_HANDLER;
  sigchld++;
  n = 0;
  if (queue_sigchld == 0)
    n = waitchld (-1, 0);
  errno = oerrno;
  SIGRETURN (n);
}

/* waitchld() reaps dead or stopped children.  It's called by wait_for and
   sigchld_handler, and runs until there aren't any children terminating any
   more.
   If BLOCK is 1, this is to be a blocking wait for a single child, although
   an arriving SIGCHLD could cause the wait to be non-blocking.  It returns
   the number of children reaped, or -1 if there are no unwaited-for child
   processes. */
static int
waitchld (wpid, block)
     pid_t wpid;
     int block;
{
  WAIT status;
  PROCESS *child;
  pid_t pid;
  int call_set_current, last_stopped_job, job, children_exited, waitpid_flags;
  static int wcontinued = WCONTINUED;	/* run-time fix for glibc problem */

  call_set_current = children_exited = 0;
  last_stopped_job = NO_JOB;

  do
    {
      /* We don't want to be notified about jobs stopping if job control
	 is not active.  XXX - was interactive_shell instead of job_control */
      waitpid_flags = (job_control && subshell_environment == 0)
			? (WUNTRACED|wcontinued)
			: 0;
      if (sigchld || block == 0)
	waitpid_flags |= WNOHANG;
      /* Check for terminating signals and exit the shell if we receive one */
      CHECK_TERMSIG;

      if (block == 1 && queue_sigchld == 0 && (waitpid_flags & WNOHANG) == 0)
	{
	  internal_warning (_("waitchld: turning on WNOHANG to avoid indefinite block"));
	  waitpid_flags |= WNOHANG;
	}

      pid = WAITPID (-1, &status, waitpid_flags);

      /* WCONTINUED may be rejected by waitpid as invalid even when defined */
      if (wcontinued && pid < 0 && errno == EINVAL)
	{
	  wcontinued = 0;
	  continue;	/* jump back to the test and retry without WCONTINUED */
	}

      /* The check for WNOHANG is to make sure we decrement sigchld only
	 if it was non-zero before we called waitpid. */
      if (sigchld > 0 && (waitpid_flags & WNOHANG))
	sigchld--;
  
      /* If waitpid returns -1 with errno == ECHILD, there are no more
	 unwaited-for child processes of this shell. */
      if (pid < 0 && errno == ECHILD)
	{
	  if (children_exited == 0)
	    return -1;
	  else
	    break;
	}

      /* If waitpid returns 0, there are running children.  If it returns -1,
	 the only other error POSIX says it can return is EINTR. */
      CHECK_TERMSIG;
      if (pid <= 0)
	continue;	/* jumps right to the test */

      /* children_exited is used to run traps on SIGCHLD.  We don't want to
         run the trap if a process is just being continued. */
      if (WIFCONTINUED(status) == 0)
	{
	  children_exited++;
	  js.c_living--;
	}

      /* Locate our PROCESS for this pid. */
      child = find_process (pid, 1, &job);	/* want living procs only */

#if defined (COPROCESS_SUPPORT)
      coproc_pidchk (pid, status);
#endif

      /* It is not an error to have a child terminate that we did
	 not have a record of.  This child could have been part of
	 a pipeline in backquote substitution.  Even so, I'm not
	 sure child is ever non-zero. */
      if (child == 0)
	{
	  if (WIFEXITED (status) || WIFSIGNALED (status))
	    js.c_reaped++;
	  continue;
	}

      /* Remember status, and whether or not the process is running. */
      child->status = status;
      child->running = WIFCONTINUED(status) ? PS_RUNNING : PS_DONE;

      if (PEXITED (child))
	{
	  js.c_totreaped++;
	  if (job != NO_JOB)
	    js.c_reaped++;
	}
        
      if (job == NO_JOB)
	continue;

      call_set_current += set_job_status_and_cleanup (job);

      if (STOPPED (job))
	last_stopped_job = job;
      else if (DEADJOB (job) && last_stopped_job == job)
	last_stopped_job = NO_JOB;
    }
  while ((sigchld || block == 0) && pid > (pid_t)0);

  /* If a job was running and became stopped, then set the current
     job.  Otherwise, don't change a thing. */
  if (call_set_current)
    {
      if (last_stopped_job != NO_JOB)
	set_current_job (last_stopped_job);
      else
	reset_current ();
    }

  /* Call a SIGCHLD trap handler for each child that exits, if one is set. */
  if (job_control && signal_is_trapped (SIGCHLD) && children_exited &&
      trap_list[SIGCHLD] != (char *)IGNORE_SIG)
    {
      if (posixly_correct && this_shell_builtin && this_shell_builtin == wait_builtin)
	{
	  interrupt_immediately = 0;
	  trap_handler (SIGCHLD);	/* set pending_traps[SIGCHLD] */
	  wait_signal_received = SIGCHLD;
	  longjmp (wait_intr_buf, 1);
	}

      run_sigchld_trap (children_exited);
    }

  /* We have successfully recorded the useful information about this process
     that has just changed state.  If we notify asynchronously, and the job
     that this process belongs to is no longer running, then notify the user
     of that fact now. */
  if (asynchronous_notification && interactive)
    notify_of_job_status ();

  return (children_exited);
}

/* Set the status of JOB and perform any necessary cleanup if the job is
   marked as JDEAD.

   Currently, the cleanup activity is restricted to handling any SIGINT
   received while waiting for a foreground job to finish. */
static int
set_job_status_and_cleanup (job)
     int job;
{
  PROCESS *child;
  int tstatus, job_state, any_stopped, any_tstped, call_set_current;
  SigHandler *temp_handler;

  child = jobs[job]->pipe;
  jobs[job]->flags &= ~J_NOTIFIED;

  call_set_current = 0;

  /*
   * COMPUTE JOB STATUS
   */

  /* If all children are not running, but any of them is  stopped, then
     the job is stopped, not dead. */
  job_state = any_stopped = any_tstped = 0;
  do
    {
      job_state |= PRUNNING (child);
#if 0
      if (PEXITED (child) && (WIFSTOPPED (child->status)))
#else
      /* Only checking for WIFSTOPPED now, not for PS_DONE */
      if (PSTOPPED (child))
#endif
	{
	  any_stopped = 1;
	  any_tstped |= interactive && job_control &&
			    (WSTOPSIG (child->status) == SIGTSTP);
	}
      child = child->next;
    }
  while (child != jobs[job]->pipe);

  /* If job_state != 0, the job is still running, so don't bother with
     setting the process exit status and job state unless we're
     transitioning from stopped to running. */
  if (job_state != 0 && JOBSTATE(job) != JSTOPPED)
    return 0;

  /*
   * SET JOB STATUS
   */

  /* The job is either stopped or dead.  Set the state of the job accordingly. */
  if (any_stopped)
    {
      jobs[job]->state = JSTOPPED;
      jobs[job]->flags &= ~J_FOREGROUND;
      call_set_current++;
      /* Suspending a job with SIGTSTP breaks all active loops. */
      if (any_tstped && loop_level)
	breaking = loop_level;
    }
  else if (job_state != 0)	/* was stopped, now running */
    {
      jobs[job]->state = JRUNNING;
      call_set_current++;
    }
  else
    {
      jobs[job]->state = JDEAD;
      js.j_ndead++;

#if 0
      if (IS_FOREGROUND (job))
	setjstatus (job);
#endif

      /* If this job has a cleanup function associated with it, call it
	 with `cleanarg' as the single argument, then set the function
	 pointer to NULL so it is not inadvertently called twice.  The
	 cleanup function is responsible for deallocating cleanarg. */
      if (jobs[job]->j_cleanup)
	{
	  (*jobs[job]->j_cleanup) (jobs[job]->cleanarg);
	  jobs[job]->j_cleanup = (sh_vptrfunc_t *)NULL;
	}
    }

  /*
   * CLEANUP
   *
   * Currently, we just do special things if we got a SIGINT while waiting
   * for a foreground job to complete
   */

  if (JOBSTATE (job) == JDEAD)
    {
      /* If we're running a shell script and we get a SIGINT with a
	 SIGINT trap handler, but the foreground job handles it and
	 does not exit due to SIGINT, run the trap handler but do not
	 otherwise act as if we got the interrupt. */
      if (wait_sigint_received && interactive_shell == 0 &&
	  WIFSIGNALED (child->status) == 0 && IS_FOREGROUND (job) &&
	  signal_is_trapped (SIGINT))
	{
	  int old_frozen;
	  wait_sigint_received = 0;
	  last_command_exit_value = process_exit_status (child->status);

	  old_frozen = jobs_list_frozen;
	  jobs_list_frozen = 1;
	  tstatus = maybe_call_trap_handler (SIGINT);
	  jobs_list_frozen = old_frozen;
	}

      /* If the foreground job is killed by SIGINT when job control is not
	 active, we need to perform some special handling.

	 The check of wait_sigint_received is a way to determine if the
	 SIGINT came from the keyboard (in which case the shell has already
	 seen it, and wait_sigint_received is non-zero, because keyboard
	 signals are sent to process groups) or via kill(2) to the foreground
	 process by another process (or itself).  If the shell did receive the
	 SIGINT, it needs to perform normal SIGINT processing. */
      else if (wait_sigint_received && (WTERMSIG (child->status) == SIGINT) &&
	      IS_FOREGROUND (job) && IS_JOBCONTROL (job) == 0)
	{
	  int old_frozen;

	  wait_sigint_received = 0;

	  /* If SIGINT is trapped, set the exit status so that the trap
	     handler can see it. */
	  if (signal_is_trapped (SIGINT))
	    last_command_exit_value = process_exit_status (child->status);

	  /* If the signal is trapped, let the trap handler get it no matter
	     what and simply return if the trap handler returns.
	    maybe_call_trap_handler() may cause dead jobs to be removed from
	    the job table because of a call to execute_command.  We work
	    around this by setting JOBS_LIST_FROZEN. */
	  old_frozen = jobs_list_frozen;
	  jobs_list_frozen = 1;
	  tstatus = maybe_call_trap_handler (SIGINT);
	  jobs_list_frozen = old_frozen;
	  if (tstatus == 0 && old_sigint_handler != INVALID_SIGNAL_HANDLER)
	    {
	      /* wait_sigint_handler () has already seen SIGINT and
		 allowed the wait builtin to jump out.  We need to
		 call the original SIGINT handler, if necessary.  If
		 the original handler is SIG_DFL, we need to resend
		 the signal to ourselves. */

	      temp_handler = old_sigint_handler;

	      /* Bogus.  If we've reset the signal handler as the result
		 of a trap caught on SIGINT, then old_sigint_handler
		 will point to trap_handler, which now knows nothing about
		 SIGINT (if we reset the sighandler to the default).
		 In this case, we have to fix things up.  What a crock. */
	      if (temp_handler == trap_handler && signal_is_trapped (SIGINT) == 0)
		  temp_handler = trap_to_sighandler (SIGINT);
		restore_sigint_handler ();
	      if (temp_handler == SIG_DFL)
		termsig_handler (SIGINT);
	      else if (temp_handler != SIG_IGN)
		(*temp_handler) (SIGINT);
	    }
	}
    }

  return call_set_current;
}

/* Build the array of values for the $PIPESTATUS variable from the set of
   exit statuses of all processes in the job J. */
static void
setjstatus (j)
     int j;
{
#if defined (ARRAY_VARS)
  register int i;
  register PROCESS *p;

  for (i = 1, p = jobs[j]->pipe; p->next != jobs[j]->pipe; p = p->next, i++)
    ;
  i++;
  if (statsize < i)
    {
      pstatuses = (int *)xrealloc (pstatuses, i * sizeof (int));
      statsize = i;
    }
  i = 0;
  p = jobs[j]->pipe;
  do
    {
      pstatuses[i++] = process_exit_status (p->status);
      p = p->next;
    }
  while (p != jobs[j]->pipe);

  pstatuses[i] = -1;	/* sentinel */
  set_pipestatus_array (pstatuses, i);
#endif
}

void
run_sigchld_trap (nchild)
     int nchild;
{
  char *trap_command;
  int i;

  /* Turn off the trap list during the call to parse_and_execute ()
     to avoid potentially infinite recursive calls.  Preserve the
     values of last_command_exit_value, last_made_pid, and the_pipeline
     around the execution of the trap commands. */
  trap_command = savestring (trap_list[SIGCHLD]);

  begin_unwind_frame ("SIGCHLD trap");
  unwind_protect_int (last_command_exit_value);
  unwind_protect_int (last_command_exit_signal);
  unwind_protect_var (last_made_pid);
  unwind_protect_int (interrupt_immediately);
  unwind_protect_int (jobs_list_frozen);
  unwind_protect_pointer (the_pipeline);
  unwind_protect_pointer (subst_assign_varlist);

  /* We have to add the commands this way because they will be run
     in reverse order of adding.  We don't want maybe_set_sigchld_trap ()
     to reference freed memory. */
  add_unwind_protect (xfree, trap_command);
  add_unwind_protect (maybe_set_sigchld_trap, trap_command);

  subst_assign_varlist = (WORD_LIST *)NULL;
  the_pipeline = (PROCESS *)NULL;

  set_impossible_sigchld_trap ();
  jobs_list_frozen = 1;
  for (i = 0; i < nchild; i++)
    {
      interrupt_immediately = 1;
      parse_and_execute (savestring (trap_command), "trap", SEVAL_NOHIST|SEVAL_RESETLINE);
    }

  run_unwind_frame ("SIGCHLD trap");
}

/* Function to call when you want to notify people of changes
   in job status.  This prints out all jobs which are pending
   notification to stderr, and marks those printed as already
   notified, thus making them candidates for cleanup. */
static void
notify_of_job_status ()
{
  register int job, termsig;
  char *dir;
  sigset_t set, oset;
  WAIT s;

  if (jobs == 0 || js.j_jobslots == 0)
    return;

  if (old_ttou != 0)
    {
      sigemptyset (&set);
      sigaddset (&set, SIGCHLD);
      sigaddset (&set, SIGTTOU);
      sigemptyset (&oset);
      sigprocmask (SIG_BLOCK, &set, &oset);
    }
  else
    queue_sigchld++;

  /* XXX could use js.j_firstj here */
  for (job = 0, dir = (char *)NULL; job < js.j_jobslots; job++)
    {
      if (jobs[job] && IS_NOTIFIED (job) == 0)
	{
	  s = raw_job_exit_status (job);
	  termsig = WTERMSIG (s);

	  /* POSIX.2 says we have to hang onto the statuses of at most the
	     last CHILD_MAX background processes if the shell is running a
	     script.  If the shell is running a script, either from a file
	     or standard input, don't print anything unless the job was
	     killed by a signal. */
	  if (startup_state == 0 && WIFSIGNALED (s) == 0 &&
		((DEADJOB (job) && IS_FOREGROUND (job) == 0) || STOPPED (job)))
	    continue;
	  
#if 0
	  /* If job control is disabled, don't print the status messages.
	     Mark dead jobs as notified so that they get cleaned up.  If
	     startup_state == 2, we were started to run `-c command', so
	     don't print anything. */
	  if ((job_control == 0 && interactive_shell) || startup_state == 2)
#else
	  /* If job control is disabled, don't print the status messages.
	     Mark dead jobs as notified so that they get cleaned up.  If
	     startup_state == 2 and subshell_environment has the
	     SUBSHELL_COMSUB bit turned on, we were started to run a command
	     substitution, so don't print anything. */
	  if ((job_control == 0 && interactive_shell) ||
	      (startup_state == 2 && (subshell_environment & SUBSHELL_COMSUB)))
#endif
	    {
	      /* POSIX.2 compatibility:  if the shell is not interactive,
		 hang onto the job corresponding to the last asynchronous
		 pid until the user has been notified of its status or does
		 a `wait'. */
	      if (DEADJOB (job) && (interactive_shell || (find_last_pid (job, 0) != last_asynchronous_pid)))
		jobs[job]->flags |= J_NOTIFIED;
	      continue;
	    }

	  /* Print info on jobs that are running in the background,
	     and on foreground jobs that were killed by anything
	     except SIGINT (and possibly SIGPIPE). */
	  switch (JOBSTATE (job))
	    {
	    case JDEAD:
	      if (interactive_shell == 0 && termsig && WIFSIGNALED (s) &&
		  termsig != SIGINT &&
#if defined (DONT_REPORT_SIGPIPE)
		  termsig != SIGPIPE &&
#endif
		  signal_is_trapped (termsig) == 0)
		{
		  /* Don't print `0' for a line number. */
		  fprintf (stderr, _("%s: line %d: "), get_name_for_error (), (line_number == 0) ? 1 : line_number);
		  pretty_print_job (job, JLIST_NONINTERACTIVE, stderr);
		}
	      else if (IS_FOREGROUND (job))
		{
#if !defined (DONT_REPORT_SIGPIPE)
		  if (termsig && WIFSIGNALED (s) && termsig != SIGINT)
#else
		  if (termsig && WIFSIGNALED (s) && termsig != SIGINT && termsig != SIGPIPE)
#endif
		    {
		      fprintf (stderr, "%s", j_strsignal (termsig));

		      if (WIFCORED (s))
			fprintf (stderr, _(" (core dumped)"));

		      fprintf (stderr, "\n");
		    }
		}
	      else if (job_control)	/* XXX job control test added */
		{
		  if (dir == 0)
		    dir = current_working_directory ();
		  pretty_print_job (job, JLIST_STANDARD, stderr);
		  if (dir && strcmp (dir, jobs[job]->wd) != 0)
		    fprintf (stderr,
			     _("(wd now: %s)\n"), polite_directory_format (dir));
		}

	      jobs[job]->flags |= J_NOTIFIED;
	      break;

	    case JSTOPPED:
	      fprintf (stderr, "\n");
	      if (dir == 0)
		dir = current_working_directory ();
	      pretty_print_job (job, JLIST_STANDARD, stderr);
	      if (dir && (strcmp (dir, jobs[job]->wd) != 0))
		fprintf (stderr,
			 _("(wd now: %s)\n"), polite_directory_format (dir));
	      jobs[job]->flags |= J_NOTIFIED;
	      break;

	    case JRUNNING:
	    case JMIXED:
	      break;

	    default:
	      programming_error ("notify_of_job_status");
	    }
	}
    }
  if (old_ttou != 0)
    sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL);
  else
    queue_sigchld--;
}

/* Initialize the job control mechanism, and set up the tty stuff. */
int
initialize_job_control (force)
     int force;
{
  pid_t t;
  int t_errno;

  t_errno = -1;
  shell_pgrp = getpgid (0);

  if (shell_pgrp == -1)
    {
      sys_error (_("initialize_job_control: getpgrp failed"));
      exit (1);
    }

  /* We can only have job control if we are interactive. */
  if (interactive == 0)
    {
      job_control = 0;
      original_pgrp = NO_PID;
      shell_tty = fileno (stderr);
    }
  else
    {
      shell_tty = -1;

      /* If forced_interactive is set, we skip the normal check that stderr
	 is attached to a tty, so we need to check here.  If it's not, we
	 need to see whether we have a controlling tty by opening /dev/tty,
	 since trying to use job control tty pgrp manipulations on a non-tty
	 is going to fail. */
      if (forced_interactive && isatty (fileno (stderr)) == 0)
	shell_tty = open ("/dev/tty", O_RDWR|O_NONBLOCK);

      /* Get our controlling terminal.  If job_control is set, or
	 interactive is set, then this is an interactive shell no
	 matter where fd 2 is directed. */
      if (shell_tty == -1)
	shell_tty = dup (fileno (stderr));	/* fd 2 */

      shell_tty = move_to_high_fd (shell_tty, 1, -1);

      /* Compensate for a bug in systems that compiled the BSD
	 rlogind with DEBUG defined, like NeXT and Alliant. */
      if (shell_pgrp == 0)
	{
	  shell_pgrp = getpid ();
	  setpgid (0, shell_pgrp);
	  tcsetpgrp (shell_tty, shell_pgrp);
	}

      while ((terminal_pgrp = tcgetpgrp (shell_tty)) != -1)
	{
	  if (shell_pgrp != terminal_pgrp)
	    {
	      SigHandler *ottin;

	      ottin = set_signal_handler(SIGTTIN, SIG_DFL);
	      kill (0, SIGTTIN);
	      set_signal_handler (SIGTTIN, ottin);
	      continue;
	    }
	  break;
	}

      if (terminal_pgrp == -1)
	t_errno = errno;

      /* Make sure that we are using the new line discipline. */
      if (set_new_line_discipline (shell_tty) < 0)
	{
	  sys_error (_("initialize_job_control: line discipline"));
	  job_control = 0;
	}
      else
	{
	  original_pgrp = shell_pgrp;
	  shell_pgrp = getpid ();

	  if ((original_pgrp != shell_pgrp) && (setpgid (0, shell_pgrp) < 0))
	    {
	      sys_error (_("initialize_job_control: setpgid"));
	      shell_pgrp = original_pgrp;
	    }

	  job_control = 1;

	  /* If (and only if) we just set our process group to our pid,
	     thereby becoming a process group leader, and the terminal
	     is not in the same process group as our (new) process group,
	     then set the terminal's process group to our (new) process
	     group.  If that fails, set our process group back to what it
	     was originally (so we can still read from the terminal) and
	     turn off job control.  */
	  if (shell_pgrp != original_pgrp && shell_pgrp != terminal_pgrp)
	    {
	      if (give_terminal_to (shell_pgrp, 0) < 0)
		{
		  t_errno = errno;
		  setpgid (0, original_pgrp);
		  shell_pgrp = original_pgrp;
		  job_control = 0;
		}
	    }

	  if (job_control && ((t = tcgetpgrp (shell_tty)) == -1 || t != shell_pgrp))
	    {
	      if (t_errno != -1)
		errno = t_errno;
	      sys_error (_("cannot set terminal process group (%d)"), t);
	      job_control = 0;
	    }
	}
      if (job_control == 0)
	internal_error (_("no job control in this shell"));
    }

  if (shell_tty != fileno (stderr))
    SET_CLOSE_ON_EXEC (shell_tty);

  set_signal_handler (SIGCHLD, sigchld_handler);

  change_flag ('m', job_control ? '-' : '+');

  if (interactive)
    get_tty_state ();

  if (js.c_childmax < 0)
    js.c_childmax = getmaxchild ();
  if (js.c_childmax < 0)
    js.c_childmax = DEFAULT_CHILD_MAX;

  return job_control;
}

#ifdef DEBUG
void
debug_print_pgrps ()
{
  itrace("original_pgrp = %ld shell_pgrp = %ld terminal_pgrp = %ld",
	 (long)original_pgrp, (long)shell_pgrp, (long)terminal_pgrp);
  itrace("tcgetpgrp(%d) -> %ld, getpgid(0) -> %ld",
	 shell_tty, (long)tcgetpgrp (shell_tty), (long)getpgid(0));
}
#endif

/* Set the line discipline to the best this system has to offer.
   Return -1 if this is not possible. */
static int
set_new_line_discipline (tty)
     int tty;
{
#if defined (NEW_TTY_DRIVER)
  int ldisc;

  if (ioctl (tty, TIOCGETD, &ldisc) < 0)
    return (-1);

  if (ldisc != NTTYDISC)
    {
      ldisc = NTTYDISC;

      if (ioctl (tty, TIOCSETD, &ldisc) < 0)
	return (-1);
    }
  return (0);
#endif /* NEW_TTY_DRIVER */

#if defined (TERMIO_TTY_DRIVER)
#  if defined (TERMIO_LDISC) && (NTTYDISC)
  if (ioctl (tty, TCGETA, &shell_tty_info) < 0)
    return (-1);

  if (shell_tty_info.c_line != NTTYDISC)
    {
      shell_tty_info.c_line = NTTYDISC;
      if (ioctl (tty, TCSETAW, &shell_tty_info) < 0)
	return (-1);
    }
#  endif /* TERMIO_LDISC && NTTYDISC */
  return (0);
#endif /* TERMIO_TTY_DRIVER */

#if defined (TERMIOS_TTY_DRIVER)
#  if defined (TERMIOS_LDISC) && defined (NTTYDISC)
  if (tcgetattr (tty, &shell_tty_info) < 0)
    return (-1);

  if (shell_tty_info.c_line != NTTYDISC)
    {
      shell_tty_info.c_line = NTTYDISC;
      if (tcsetattr (tty, TCSADRAIN, &shell_tty_info) < 0)
	return (-1);
    }
#  endif /* TERMIOS_LDISC && NTTYDISC */
  return (0);
#endif /* TERMIOS_TTY_DRIVER */

#if !defined (NEW_TTY_DRIVER) && !defined (TERMIO_TTY_DRIVER) && !defined (TERMIOS_TTY_DRIVER)
  return (-1);
#endif
}

/* Setup this shell to handle C-C, etc. */
void
initialize_job_signals ()
{
  if (interactive)
    {
      set_signal_handler (SIGINT, sigint_sighandler);
      set_signal_handler (SIGTSTP, SIG_IGN);
      set_signal_handler (SIGTTOU, SIG_IGN);
      set_signal_handler (SIGTTIN, SIG_IGN);
    }
  else if (job_control)
    {
      old_tstp = set_signal_handler (SIGTSTP, sigstop_sighandler);
      old_ttin = set_signal_handler (SIGTTIN, sigstop_sighandler);
      old_ttou = set_signal_handler (SIGTTOU, sigstop_sighandler);
    }
  /* Leave these things alone for non-interactive shells without job
     control. */
}

/* Here we handle CONT signals. */
static sighandler
sigcont_sighandler (sig)
     int sig;
{
  initialize_job_signals ();
  set_signal_handler (SIGCONT, old_cont);
  kill (getpid (), SIGCONT);

  SIGRETURN (0);
}

/* Here we handle stop signals while we are running not as a login shell. */
static sighandler
sigstop_sighandler (sig)
     int sig;
{
  set_signal_handler (SIGTSTP, old_tstp);
  set_signal_handler (SIGTTOU, old_ttou);
  set_signal_handler (SIGTTIN, old_ttin);

  old_cont = set_signal_handler (SIGCONT, sigcont_sighandler);

  give_terminal_to (shell_pgrp, 0);

  kill (getpid (), sig);

  SIGRETURN (0);
}

/* Give the terminal to PGRP.  */
int
give_terminal_to (pgrp, force)
     pid_t pgrp;
     int force;
{
  sigset_t set, oset;
  int r, e;

  r = 0;
  if (job_control || force)
    {
      sigemptyset (&set);
      sigaddset (&set, SIGTTOU);
      sigaddset (&set, SIGTTIN);
      sigaddset (&set, SIGTSTP);
      sigaddset (&set, SIGCHLD);
      sigemptyset (&oset);
      sigprocmask (SIG_BLOCK, &set, &oset);

      if (tcsetpgrp (shell_tty, pgrp) < 0)
	{
	  /* Maybe we should print an error message? */
#if 0
	  sys_error ("tcsetpgrp(%d) failed: pid %ld to pgrp %ld",
	    shell_tty, (long)getpid(), (long)pgrp);
#endif
	  r = -1;
	  e = errno;
	}
      else
	terminal_pgrp = pgrp;
      sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL);
    }

  if (r == -1)
    errno = e;

  return r;
}

/* Give terminal to NPGRP iff it's currently owned by OPGRP.  FLAGS are the
   flags to pass to give_terminal_to(). */
static int
maybe_give_terminal_to (opgrp, npgrp, flags)
     pid_t opgrp, npgrp;
     int flags;
{
  int tpgrp;

  tpgrp = tcgetpgrp (shell_tty);
  if (tpgrp < 0 && errno == ENOTTY)
    return -1;
  if (tpgrp == npgrp)
    {
      terminal_pgrp = npgrp;
      return 0;
    }
  else if (tpgrp != opgrp)
    {
#if defined (DEBUG)
      internal_warning ("maybe_give_terminal_to: terminal pgrp == %d shell pgrp = %d new pgrp = %d", tpgrp, opgrp, npgrp);
#endif
      return -1;
    }
  else
    return (give_terminal_to (npgrp, flags));     
}

/* Clear out any jobs in the job array.  This is intended to be used by
   children of the shell, who should not have any job structures as baggage
   when they start executing (forking subshells for parenthesized execution
   and functions with pipes are the two that spring to mind).  If RUNNING_ONLY
   is nonzero, only running jobs are removed from the table. */
void
delete_all_jobs (running_only)
     int running_only;
{
  register int i;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);

  /* XXX - need to set j_lastj, j_firstj appropriately if running_only != 0. */
  if (js.j_jobslots)
    {
      js.j_current = js.j_previous = NO_JOB;

      /* XXX could use js.j_firstj here */
      for (i = 0; i < js.j_jobslots; i++)
	{
#if defined (DEBUG)
	  if (i < js.j_firstj && jobs[i])
	    itrace("delete_all_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
	  if (i > js.j_lastj && jobs[i])
	    itrace("delete_all_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
	  if (jobs[i] && (running_only == 0 || (running_only && RUNNING(i))))
	    delete_job (i, DEL_WARNSTOPPED);
	}
      if (running_only == 0)
	{
	  free ((char *)jobs);
	  js.j_jobslots = 0;
	  js.j_firstj = js.j_lastj = js.j_njobs = 0;
	}
    }

  if (running_only == 0)
    bgp_clear ();

  UNBLOCK_CHILD (oset);
}

/* Mark all jobs in the job array so that they don't get a SIGHUP when the
   shell gets one.  If RUNNING_ONLY is nonzero, mark only running jobs. */
void
nohup_all_jobs (running_only)
     int running_only;
{
  register int i;
  sigset_t set, oset;

  BLOCK_CHILD (set, oset);

  if (js.j_jobslots)
    {
      /* XXX could use js.j_firstj here */
      for (i = 0; i < js.j_jobslots; i++)
	if (jobs[i] && (running_only == 0 || (running_only && RUNNING(i))))
	  nohup_job (i);
    }

  UNBLOCK_CHILD (oset);
}

int
count_all_jobs ()
{
  int i, n;
  sigset_t set, oset;

  /* This really counts all non-dead jobs. */
  BLOCK_CHILD (set, oset);
  /* XXX could use js.j_firstj here */
  for (i = n = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("count_all_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("count_all_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
      if (jobs[i] && DEADJOB(i) == 0)
	n++;
    }
  UNBLOCK_CHILD (oset);
  return n;
}

static void
mark_all_jobs_as_dead ()
{
  register int i;
  sigset_t set, oset;

  if (js.j_jobslots == 0)
    return;

  BLOCK_CHILD (set, oset);

  /* XXX could use js.j_firstj here */
  for (i = 0; i < js.j_jobslots; i++)
    if (jobs[i])
      {
	jobs[i]->state = JDEAD;
	js.j_ndead++;
      }

  UNBLOCK_CHILD (oset);
}

/* Mark all dead jobs as notified, so delete_job () cleans them out
   of the job table properly.  POSIX.2 says we need to save the
   status of the last CHILD_MAX jobs, so we count the number of dead
   jobs and mark only enough as notified to save CHILD_MAX statuses. */
static void
mark_dead_jobs_as_notified (force)
     int force;
{
  register int i, ndead, ndeadproc;
  sigset_t set, oset;

  if (js.j_jobslots == 0)
    return;

  BLOCK_CHILD (set, oset);

  /* If FORCE is non-zero, we don't have to keep CHILD_MAX statuses
     around; just run through the array. */
  if (force)
    {
    /* XXX could use js.j_firstj here */
      for (i = 0; i < js.j_jobslots; i++)
	{
	  if (jobs[i] && DEADJOB (i) && (interactive_shell || (find_last_pid (i, 0) != last_asynchronous_pid)))
	    jobs[i]->flags |= J_NOTIFIED;
	}
      UNBLOCK_CHILD (oset);
      return;
    }

  /* Mark enough dead jobs as notified to keep CHILD_MAX processes left in the
     array with the corresponding not marked as notified.  This is a better
     way to avoid pid aliasing and reuse problems than keeping the POSIX-
     mandated CHILD_MAX jobs around.  delete_job() takes care of keeping the
     bgpids list regulated. */
          
  /* Count the number of dead jobs */
  /* XXX could use js.j_firstj here */
  for (i = ndead = ndeadproc = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("mark_dead_jobs_as_notified: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("mark_dead_jobs_as_notified: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
      if (jobs[i] && DEADJOB (i))
	{
	  ndead++;
	  ndeadproc += processes_in_job (i);
	}
    }

#ifdef DEBUG
  if (ndeadproc != js.c_reaped)
    itrace("mark_dead_jobs_as_notified: ndeadproc (%d) != js.c_reaped (%d)", ndeadproc, js.c_reaped);
  if (ndead != js.j_ndead)
    itrace("mark_dead_jobs_as_notified: ndead (%d) != js.j_ndead (%d)", ndead, js.j_ndead);
#endif

  if (js.c_childmax < 0)
    js.c_childmax = getmaxchild ();
  if (js.c_childmax < 0)
    js.c_childmax = DEFAULT_CHILD_MAX;

  /* Don't do anything if the number of dead processes is less than CHILD_MAX
     and we're not forcing a cleanup. */
  if (ndeadproc <= js.c_childmax)
    {
      UNBLOCK_CHILD (oset);
      return;
    }

#if 0
itrace("mark_dead_jobs_as_notified: child_max = %d ndead = %d ndeadproc = %d", js.c_childmax, ndead, ndeadproc);
#endif

  /* Mark enough dead jobs as notified that we keep CHILD_MAX jobs in
     the list.  This isn't exactly right yet; changes need to be made
     to stop_pipeline so we don't mark the newer jobs after we've
     created CHILD_MAX slots in the jobs array.  This needs to be
     integrated with a way to keep the jobs array from growing without
     bound.  Maybe we wrap back around to 0 after we reach some max
     limit, and there are sufficient job slots free (keep track of total
     size of jobs array (js.j_jobslots) and running count of number of jobs
     in jobs array.  Then keep a job index corresponding to the `oldest job'
     and start this loop there, wrapping around as necessary.  In effect,
     we turn the list into a circular buffer. */
  /* XXX could use js.j_firstj here */
  for (i = 0; i < js.j_jobslots; i++)
    {
      if (jobs[i] && DEADJOB (i) && (interactive_shell || (find_last_pid (i, 0) != last_asynchronous_pid)))
	{
#if defined (DEBUG)
	  if (i < js.j_firstj && jobs[i])
	    itrace("mark_dead_jobs_as_notified: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
	  if (i > js.j_lastj && jobs[i])
	    itrace("mark_dead_jobs_as_notified: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif
	  /* If marking this job as notified would drop us down below
	     child_max, don't mark it so we can keep at least child_max
	     statuses.  XXX -- need to check what Posix actually says
	     about keeping statuses. */
	  if ((ndeadproc -= processes_in_job (i)) <= js.c_childmax)
	    break;
	  jobs[i]->flags |= J_NOTIFIED;
	}
    }

  UNBLOCK_CHILD (oset);
}

/* Here to allow other parts of the shell (like the trap stuff) to
   freeze and unfreeze the jobs list. */
void
freeze_jobs_list ()
{
  jobs_list_frozen = 1;
}

void
unfreeze_jobs_list ()
{
  jobs_list_frozen = 0;
}

/* Allow or disallow job control to take place.  Returns the old value
   of job_control. */
int
set_job_control (arg)
     int arg;
{
  int old;

  old = job_control;
  job_control = arg;

  /* If we're turning on job control, reset pipeline_pgrp so make_child will
     put new child processes into the right pgrp */
  if (job_control != old && job_control)
    pipeline_pgrp = 0;

  return (old);
}

/* Turn off all traces of job control.  This is run by children of the shell
   which are going to do shellsy things, like wait (), etc. */
void
without_job_control ()
{
  stop_making_children ();
  start_pipeline ();
#if defined (PGRP_PIPE)
  sh_closepipe (pgrp_pipe);
#endif
  delete_all_jobs (0);
  set_job_control (0);
}

/* If this shell is interactive, terminate all stopped jobs and
   restore the original terminal process group.  This is done
   before the `exec' builtin calls shell_execve. */
void
end_job_control ()
{
  if (interactive_shell)		/* XXX - should it be interactive? */
    {
      terminate_stopped_jobs ();

      if (original_pgrp >= 0)
	give_terminal_to (original_pgrp, 1);
    }

  if (original_pgrp >= 0)
    setpgid (0, original_pgrp);
}

/* Restart job control by closing shell tty and reinitializing.  This is
   called after an exec fails in an interactive shell and we do not exit. */
void
restart_job_control ()
{
  if (shell_tty != -1)
    close (shell_tty);
  initialize_job_control (0);
}

/* Set the handler to run when the shell receives a SIGCHLD signal. */
void
set_sigchld_handler ()
{
  set_signal_handler (SIGCHLD, sigchld_handler);
}

#if defined (PGRP_PIPE)
/* Read from the read end of a pipe.  This is how the process group leader
   blocks until all of the processes in a pipeline have been made. */
static void
pipe_read (pp)
     int *pp;
{
  char ch;

  if (pp[1] >= 0)
    {
      close (pp[1]);
      pp[1] = -1;
    }

  if (pp[0] >= 0)
    {
      while (read (pp[0], &ch, 1) == -1 && errno == EINTR)
	;
    }
}

/* Functional interface closes our local-to-job-control pipes. */
void
close_pgrp_pipe ()
{
  sh_closepipe (pgrp_pipe);
}

void
save_pgrp_pipe (p, clear)
     int *p;
     int clear;
{
  p[0] = pgrp_pipe[0];
  p[1] = pgrp_pipe[1];
  if (clear)
    pgrp_pipe[0] = pgrp_pipe[1] = -1;
}

void
restore_pgrp_pipe (p)
     int *p;
{
  pgrp_pipe[0] = p[0];
  pgrp_pipe[1] = p[1];
}

#endif /* PGRP_PIPE */