view toys/which.c @ 239:4f1ca01db000

Fluff out hello.c to supply more example code as a skeleton for new commands, and update a chunk of code.html (much more to do there).
author Rob Landley <>
date Sun, 20 Jan 2008 19:00:16 -0600
parents 163498bf547b
children 5a0faa267866
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/* vi: set sw=4 ts=4:
 * which.c - Find executable files in $PATH.
 * Copyright 2006 Rob landley <>
 * Not in SUSv3.


config WHICH
	bool "which"
	default y
	  usage: which [-a] filename ...

	  Search $PATH for executable files matching filename(s).

	  -a	Show all matches
#include "toys.h"

#define OPT_a   1

// Find an exectuable file either at a path with a slash in it (absolute or
// relative to current directory), or in $PATH.  Returns absolute path to file,
// or NULL if not found.

static int which_in_path(char *filename)
	struct string_list *list;

	// If they gave us a path, don't worry about $PATH or -a

	if (index(filename, '/')) {
		// Confirm it has the executable bit set, and it's not a directory.
		if (!access(filename, X_OK)) {
			struct stat st;

			if (!stat(filename, &st) && S_ISREG(st.st_mode)) {
				return 0;
			return 1;

	// Search $PATH for matches.
	list = find_in_path(getenv("PATH"), filename);
	if (!list) return 1;

	// Print out matches
	while (list) {
		if (!access(list->str, X_OK)) {
			// If we should stop at one match, do so
			if (toys.optflags & OPT_a) {
				llist_free(list, NULL);

	return 0;

void which_main(void)
	if (!*toys.optargs) toys.exitval++;
	else {
		int i;
		for (i=0; toys.optargs[i]; i++)
			toys.exitval |= which_in_path(toys.optargs[i]);