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glibc  2.9
tst-fork2.c
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00001 /* Copyright (C) 2002 Free Software Foundation, Inc.
00002    This file is part of the GNU C Library.
00003    Contributed by Roland McGrath <roland@redhat.com>, 2002.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #include <errno.h>
00021 #include <pthread.h>
00022 #include <stdio.h>
00023 #include <stdlib.h>
00024 #include <unistd.h>
00025 #include <sys/wait.h>
00026 
00027 
00028 static pid_t initial_pid;
00029 
00030 
00031 static void *
00032 tf (void *arg)
00033 {
00034   if (getppid () != initial_pid)
00035     {
00036       printf ("getppid in thread returned %ld, expected %ld\n",
00037              (long int) getppid (), (long int) initial_pid);
00038       return (void *) -1;
00039     }
00040 
00041   return NULL;
00042 }
00043 
00044 
00045 int
00046 main (void)
00047 {
00048   initial_pid = getpid ();
00049 
00050   pid_t child = fork ();
00051   if (child == 0)
00052     {
00053       if (getppid () != initial_pid)
00054        {
00055          printf ("first getppid returned %ld, expected %ld\n",
00056                 (long int) getppid (), (long int) initial_pid);
00057          exit (1);
00058        }
00059 
00060       pthread_t th;
00061       if (pthread_create (&th, NULL, tf, NULL) != 0)
00062        {
00063          puts ("pthread_create failed");
00064          exit (1);
00065        }
00066 
00067       void *result;
00068       if (pthread_join (th, &result) != 0)
00069        {
00070          puts ("pthread_join failed");
00071          exit  (1);
00072        }
00073 
00074       exit (result == NULL ? 0 : 1);
00075     }
00076   else if (child == -1)
00077     {
00078       puts ("initial fork failed");
00079       return 1;
00080     }
00081 
00082   int status;
00083   if (TEMP_FAILURE_RETRY (waitpid (child, &status, 0)) != child)
00084     {
00085       printf ("waitpid failed: %m\n");
00086       return 1;
00087     }
00088 
00089   return status;
00090 }