minix/lib/libc/sys/getppid.c


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#include <sys/cdefs.h>
#include "namespace.h"
#include <lib.h>

#include <string.h>
#include <unistd.h>

pid_t getppid(void)
{
  message m;

  memset(&m, 0, sizeof(m));
  /* POSIX says that this function is always successful and that no
   * return value is reserved to indicate an error.  Minix syscalls
   * are not always successful and Minix returns the reserved value
   * (pid_t) -1 when there is an error.
   */
  if (_syscall(PM_PROC_NR, PM_GETPID, &m) < 0) return(-1);
  return(m.m_pm_lc_getpid.parent_pid);
}