if (grbuflen == -1)
if (grbuflen == (size_t) -1L)
grantpt (int fd){  int retval = -1;#ifdef PATH_MAX  char _buf[PATH_MAX];#else  char _buf[512];#endif  char *buf = _buf;  struct stat64 st;  char *grtmpbuf;  struct group grbuf;  size_t grbuflen = __sysconf (_SC_GETGR_R_SIZE_MAX);  struct group *p;  uid_t uid;  gid_t gid;  pid_t pid;  if (pts_name (fd, &buf, sizeof (_buf)))    return -1;  if (__xstat64 (_STAT_VER, buf, &st) < 0)    goto cleanup;  /* Make sure that we own the device.  */  uid = __getuid ();  if (st.st_uid != uid)    {      if (__chown (buf, uid, st.st_gid) < 0)	goto helper;    }  /* Get the group ID of the special `tty' group.  */  if (grbuflen == -1)    /* `sysconf' does not support _SC_GETGR_R_SIZE_MAX.       Try a moderate value.  */    grbuflen = 1024;  grtmpbuf = (char *) __alloca (grbuflen);  __getgrnam_r (TTY_GROUP, &grbuf, grtmpbuf, grbuflen, &p);  gid = p ? p->gr_gid : __getgid ();  /* Make sure the group of the device is that special group.  */  if (st.st_gid != gid)    {      if (__chown (buf, uid, gid) < 0)	goto helper;    }  /* Make sure the permission mode is set to readable and writable by     the owner, and writable by the group.  */  if ((st.st_mode & ACCESSPERMS) != (S_IRUSR|S_IWUSR|S_IWGRP))    {      if (__chmod (buf, S_IRUSR|S_IWUSR|S_IWGRP) < 0)	goto helper;    }  retval = 0;  goto cleanup;  /* We have to use the helper program.  */ helper:  pid = __fork ();  if (pid == -1)    goto cleanup;  else if (pid == 0)    {      /* Disable core dumps.  */      struct rlimit rl = { 0, 0 };      __setrlimit (RLIMIT_CORE, &rl);      /* We pass the master pseudo terminal as file descriptor PTY_FILENO.  */      if (fd != PTY_FILENO)	if (__dup2 (fd, PTY_FILENO) < 0)	  _exit (FAIL_EBADF);      execle (_PATH_PT_CHOWN, basename (_PATH_PT_CHOWN), NULL, NULL);      _exit (FAIL_EXEC);    }  else    {      int w;      if (__waitpid (pid, &w, 0) == -1)	goto cleanup;      if (!WIFEXITED (w))	__set_errno (ENOEXEC);      else	switch (WEXITSTATUS(w))	  {	  case 0:	    retval = 0;	    break;	  case FAIL_EBADF:	    __set_errno (EBADF);	    break;	  case FAIL_EINVAL:	    __set_errno (EINVAL);	    break;	  case FAIL_EACCES:	    __set_errno (EACCES);	    break;	  case FAIL_EXEC:	    __set_errno (ENOEXEC);	    break;	  default:	    assert(! "getpt: internal error: invalid exit code from pt_chown");	  }    } cleanup:  if (buf != _buf)    free (buf);  return retval;}