C++ (Cpp) fd_get_write_lock Exemples

Exemple #1

Fichier : cpu_frequency.c Projet : asanchez1987/slurm

static int _fd_lock_retry(int fd)
{
	int i, rc;

	for (i = 0; i < 10; i++) {
		if (i)
			usleep(1000);	/* 1000 usec */
		rc = fd_get_write_lock(fd);
		if (rc == 0)
			break;
		if ((errno != EACCES) && (errno != EAGAIN))
			break;	/* Lock held by other job */
	}
	return rc;
}

Exemple #2

Fichier : daemonize.c Projet : IFCA/slurm

int
create_pidfile(const char *pidfile, uid_t uid)
{
	FILE *fp;
	int fd = -1;

	xassert(pidfile != NULL);
	xassert(pidfile[0] == '/');

	if (!(fp = fopen(pidfile, "w"))) {
		error("Unable to open pidfile `%s': %m", pidfile);
		return -1;
	}

	fd = fileno(fp);

	if (fd_get_write_lock(fd) < 0) {
		error ("Unable to lock pidfile `%s': %m", pidfile);
		fd = -1;
		goto error;
	}

	if (fprintf(fp, "%lu\n", (unsigned long) getpid()) == EOF) {
		error("Unable to write to pidfile `%s': %m", pidfile);
		fd = -1;
		goto error;
	}

	fflush(fp);

	if (uid && (fchown(fd, uid, -1) < 0))
		error ("Unable to reset owner of pidfile: %m");

	return fd;

  error:
	(void)fclose(fp); /* Ignore errors */

	if (unlink(pidfile) < 0)
		error("Unable to remove pidfile `%s': %m", pidfile);
	return -1;
}