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-rw-r--r--linuxthreads/Examples/ex8.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/linuxthreads/Examples/ex8.c b/linuxthreads/Examples/ex8.c
new file mode 100644
index 0000000000..89ad8ae5d5
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+++ b/linuxthreads/Examples/ex8.c
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+/* Tests for fork in multi-threaded environment.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 2000.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <errno.h>
+#include <error.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <wait.h>
+
+enum
+{
+  PREPARE_BIT = 1,
+  PARENT_BIT = 2,
+  CHILD_BIT = 4
+};
+
+static int var;
+
+static void
+prepare (void)
+{
+  var |= PREPARE_BIT;
+}
+
+static void
+parent (void)
+{
+  var |= PARENT_BIT;
+}
+
+static void
+child (void)
+{
+  var |= CHILD_BIT;
+}
+
+
+static void *thread (void *arg);
+
+
+int
+main (void)
+{
+  pthread_t th;
+  void *res;
+
+  pthread_atfork (prepare, parent, child);
+
+  if (pthread_create (&th, NULL, thread, NULL) != 0)
+    error (EXIT_FAILURE, 0, "cannot create thread");
+
+  pthread_join (th, &res);
+
+  return (int) res;
+}
+
+
+static void *
+thread (void *arg)
+{
+  int status;
+  pid_t pid;
+
+  pid = fork ();
+  if (pid == 0)
+    {
+      /* We check whether the `prepare' and `child' function ran.  */
+      exit (var != (PREPARE_BIT | CHILD_BIT));
+    }
+  else if (pid == (pid_t) -1)
+    error (EXIT_FAILURE, errno, "cannot fork");
+
+  if (waitpid (pid, &status, 0) != pid)
+    error (EXIT_FAILURE, errno, "wrong child");
+
+  if (WTERMSIG (status) != 0)
+    error (EXIT_FAILURE, 0, "Child terminated incorrectly");
+  status = WEXITSTATUS (status);
+
+  if (status == 0)
+    status = var != (PREPARE_BIT | PARENT_BIT);
+
+  return (void *) status;
+}