linux/tools/testing/selftests/proc/self.c

/*
 * Copyright © 2018 Alexey Dobriyan <[email protected]>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
// Test that /proc/self gives correct TGID.
#undef NDEBUG
#include <assert.h>
#include <stdio.h>
#include <unistd.h>

#include "proc.h"

int main(void)
{
	char buf1[64], buf2[64];
	pid_t pid;
	ssize_t rv;

	pid = sys_getpid();
	snprintf(buf1, sizeof(buf1), "%u", pid);

	rv = readlink("/proc/self", buf2, sizeof(buf2));
	assert(rv == strlen(buf1));
	buf2[rv] = '\0';
	assert(streq(buf1, buf2));

	return 0;
}