int daemon_proc = 0; /* set to 0 if stdout/stderr available, else set to 1 */

static void err_doit (int errnoflag, int level, const char *fmt, va_list ap) {

    int errno_save = errno, n;

    char buf[MAXLINE+1];

    vsnprintf (buf, MAXLINE, fmt, ap);

    n = strlen(buf);

    if (errnoflag)

        snprintf (buf+n, MAXLINE-n, ": %s", strerror(errno_save));

    strcat (buf, "\n");

    if (daemon_proc)

        syslog (level, buf);

    else {

        fflush (stdout);

        fprintf (stderr, "%s", buf);

        fflush (stderr);

    return;

}

void err_ret (const char *fmt, ...) {

    va_list ap;

    va_start (ap, fmt);

    err_doit (1, LOG_INFO, fmt, ap);

    va_end (ap);

    return;

}

void err_sys (const char *fmt, ...) {

    va_list ap;

    va_start (ap, fmt);

    err_doit (1, LOG_ERR, fmt, ap);

    va_end (ap);

    exit (1);

void err_msg (const char *fmt, ...) {

    va_list ap;

    va_start (ap, fmt);

    err_doit (0, LOG_INFO, fmt, ap);

    va_end (ap);

    return;

}

void err_quit (const char *fmt, ...) {

    va_list ap;

    va_start (ap, fmt);

    err_doit (0, LOG_ERR, fmt, ap);

    va_end (ap);

    exit (1);

}

void err_dump (const char *fmt, ...) {

    va_list ap;

    va_start (ap, fmt);

    err_doit (1, LOG_ERR, fmt, ap);

    va_end (ap);

    abort();

}