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Like which(1) unix command. Find the first instance of an executable in the PATH.
Branch: master


latest commit c80a08e9f8
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bin should 0755 the bin
test Use windows exe semantics on cygwin & msys
LICENSE isc license Update docs
package.json v1.1.1
which.js test +g exes against secondary groups, if available


Like the unix which utility.

Finds the first instance of a specified executable in the PATH environment variable. Does not cache the results, so hash -r is not needed when the PATH changes.


var which = require('which')

// async usage
which('node', function (er, resolvedPath) {
  // er is returned if no "node" is found on the PATH
  // if it is found, then the absolute path to the exec is returned

// sync usage
// throws if not found
var resolved = which.sync('node')

// Pass options to override the PATH and PATHEXT environment vars.
which('node', { path: someOtherPath }, function (er, resolved) {
  if (er)
    throw er
  console.log('found at %j', resolved)


If you pass in options, then path and pathExt are relevant.

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