Function kwsysProcessCreate

Source/kwsys/ProcessUNIX.c:1710–1888

#endif

static int kwsysProcessCreate(kwsysProcess* cp, int prIndex,
                              kwsysProcessCreateInformation* si)
{
  sigset_t mask;
  sigset_t old_mask;
  int pgidPipe[2];
  char tmp;
  ssize_t readRes;

  /* Create the error reporting pipe.  */
  if (pipe(si->ErrorPipe) < 0) {
    return 0;
  }

  /* Create a pipe for detecting that the child process has created a process
     group and session.  */
  if (pipe(pgidPipe) < 0) {
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[0]);
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[1]);
    return 0;
  }

  /* Set close-on-exec flag on the pipe's write end.  */
  if (fcntl(si->ErrorPipe[1], F_SETFD, FD_CLOEXEC) < 0 ||
      fcntl(pgidPipe[1], F_SETFD, FD_CLOEXEC) < 0) {
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[0]);
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[1]);
    kwsysProcessCleanupDescriptor(&pgidPipe[0]);
    kwsysProcessCleanupDescriptor(&pgidPipe[1]);
    return 0;
  }

  /* Block SIGINT / SIGTERM while we start.  The purpose is so that our signal
     handler doesn't get called from the child process after the fork and
     before the exec, and subsequently start kill()'ing PIDs from ForkPIDs. */
  sigemptyset(&mask);
  sigaddset(&mask, SIGINT);
  sigaddset(&mask, SIGTERM);
  if (sigprocmask(SIG_BLOCK, &mask, &old_mask) < 0) {
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[0]);
    kwsysProcessCleanupDescriptor(&si->ErrorPipe[1]);
    kwsysProcessCleanupDescriptor(&pgidPipe[0]);
    kwsysProcessCleanupDescriptor(&pgidPipe[1]);
    return 0;
  }

/* Fork off a child process.  */
#if defined(__VMS)
  /* VMS needs vfork and execvp to be in the same function because
     they use setjmp/longjmp to run the child startup code in the
     parent!  TODO: OptionDetach.  Also
     TODO:  CreateProcessGroup.  */
  cp->ForkPIDs[prIndex] = vfork();
#else
  cp->ForkPIDs[prIndex] = kwsysProcessFork(cp, si);
#endif
  if (cp->ForkPIDs[prIndex] < 0) {
    sigprocmask(SIG_SETMASK, &old_mask, 0);