which

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.

USAGE

```javascript 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 })

// or promise which('node').then(resolvedPath => { ... }).catch(er => { ... not found ... })

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

// if nothrow option is used, returns null if not found resolved = which.sync('node', {nothrow: true})

// 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) }) ```

CLI USAGE

Same as the BSD which(1) binary.

usage: which [-as] program ...

OPTIONS

You may pass an options object as the second argument.

• path: Use instead of the PATH environment variable.
• pathExt: Use instead of the PATHEXT environment variable.
• all: Return all matches, instead of just the first one. Note that this means the function returns an array of strings instead of a single string.