uid test utility

src/tools/testuid.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2014-2018 Firejail Authors
+ *
+ * This file is part of firejail project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+// compile: gcc -o testuid testuid.c
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+
+static void print_status(void) {
+	FILE *fp = fopen("/proc/self/status", "r");
+	if (!fp) {
+		fprintf(stderr, "Error, cannot open staus file\n");
+		exit(1);
+	}
+
+	char buf[4096];
+	while (fgets(buf, 4096, fp)) {
+		if (strncmp(buf, "Uid", 3) == 0 || strncmp(buf, "Gid", 3) == 0)
+			printf("%s", buf);
+	}
+
+	fclose(fp);
+}
+
+int main(void) {
+	print_status();
+	return 0;
+}