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int	read_pid_file(const char *pidfile, pid_t *pid, char *error, size_t max_error_len)
{
	int	ret = FAIL;
	FILE	*fpid;

	if (NULL == (fpid = fopen(pidfile, "r")))
	{
		zbx_snprintf(error, max_error_len, "cannot open PID file [%s]: %s", pidfile, zbx_strerror(errno));
		return ret;
	}

	if (1 == fscanf(fpid, "%d", (int *)pid))
		ret = SUCCEED;
	else
		zbx_snprintf(error, max_error_len, "cannot retrieve PID from file [%s]", pidfile);

	zbx_fclose(fpid);

	return ret;
}