src/tests/system/libroot/posix/setpgid_test.cpp

   1 #include <errno.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <unistd.h>
   6
   7
   8 int
   9 main()
  10 {
  11         pid_t parentPID = getpid();
  12         printf("parent pid: %d\n", parentPID);
  13         printf("parent pgid: %d\n", getpgrp());
  14
  15         pid_t childPID = fork();
  16         if (childPID < 0) {
  17                 fprintf(stderr, "fork() failed: %s\n", strerror(errno));
  18                 exit(1);
  19         } else if (childPID == 0) {
  20                 // child
  21                 childPID = getpid();
  22                 printf("child  pid: %d, pgid: %d\n", childPID, getpgrp());
  23
  24                 printf("child  setpgid(0, 0)\n");
  25                 if (setpgid(0, 0) < 0) {
  26                         fprintf(stderr, "child: first setpgid() failed: %s\n", strerror(errno));
  27                         exit(1);
  28                 }
  29 //              printf("child  setsid()\n");
  30 //              if (setsid() < 0) {
  31 //                      fprintf(stderr, "child: setsid() failed: %s\n", strerror(errno));
  32 //                      exit(1);
  33 //              }
  34
  35                 printf("child  pgid: %d\n", getpgrp());
  36
  37                 pid_t grandChildPID = fork();
  38                 if (grandChildPID < 0) {
  39                         fprintf(stderr, "fork() 2 failed: %s\n", strerror(errno));
  40                         exit(1);
  41                 } else if (grandChildPID == 0) {
  42                         // grand child
  43                         grandChildPID = getpid();
  44                         printf("gchild pid: %d, pgid: %d\n", grandChildPID, getpgrp());
  45                         sleep(2);
  46                         printf("gchild pid: %d, pgid: %d\n", grandChildPID, getpgrp());
  47                 } else {
  48                         // child
  49                         sleep(1);
  50
  51                         printf("child  setpgid(0, %d)\n", parentPID);
  52                         if (setpgid(0, parentPID) < 0) {
  53 //                      printf("child  setpgid(0, 0)\n");
  54 //                      if (setpgid(0, 0) < 0) {
  55                                 fprintf(stderr, "child: second setpgid() failed: %s\n", strerror(errno));
  56                                 exit(1);
  57                         }
  58
  59                         printf("child  pgid: %d\n", getpgrp());
  60                 }
  61
  62         } else {
  63                 // parent
  64                 sleep(3);
  65         }
  66
  67         return 0;
  68 }