Security fix! Correct handling of seteuid() return value See Debian bug #638002, reported by John Lightsey. When possible the (already available) set_euidgid() function is used. Additionally, it is unnecessary to change the identity when writing into an already open file descriptor. This should fix the problem.

#include <glib.h>
#include <stdio.h>
#include <stdlib.h>

#include "base64.h"

int
main()
{
	gchar line[100];
	gchar *buf;
	gint size;

	while (fgets(line, 100, stdin)) {
		buf = base64_decode(line, &size);
		fwrite(buf, size, 1, stdout);
		g_free(buf);
	}
	exit(0);
}