view toys/other/which.c @ 1322:b91284c2e569 draft

Make "losetup /dev/loop0 filename" work. Sigh. Implement the complex cases and you screw up the simple cases you already tested...
author Rob Landley <>
date Thu, 29 May 2014 06:29:12 -0500
parents 786841fdb1e0
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/* which.c - Find executable files in $PATH.
 * Copyright 2006 Rob landley <>


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"

// 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 (strchr(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) {
        llist_traverse(list, free);

  return 0;

void which_main(void)
  int i;

  for (i=0; toys.optargs[i]; i++)
    toys.exitval |= which_in_path(toys.optargs[i]);