util-linux/rdev.c

/* vi: set sw=4 ts=4: */
/*
 * rdev - print device node associated with a filesystem
 *
 * Copyright (c) 2008 Nuovation System Designs, LLC
 *   Grant Erickson <gerickson@nuovations.com>
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 *
 */
//config:config RDEV
//config:	bool "rdev (1.4 kb)"
//config:	default y
//config:	help
//config:	Print the device node associated with the filesystem mounted at '/'.

//applet:IF_RDEV(APPLET(rdev, BB_DIR_USR_SBIN, BB_SUID_DROP))

//kbuild:lib-$(CONFIG_RDEV) += rdev.o

//usage:#define rdev_trivial_usage
//usage:       ""
//usage:#define rdev_full_usage "\n\n"
//usage:       "Print the device node associated with the filesystem mounted at '/'"
//usage:
//usage:#define rdev_example_usage
//usage:       "$ rdev\n"
//usage:       "/dev/mtdblock9 /\n"

#include "libbb.h"

int rdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int rdev_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
{
	const char *root_device = find_block_device("/");

	if (root_device) {
		printf("%s /\n", root_device);
		return EXIT_SUCCESS;
	}
	return EXIT_FAILURE;
}