process - How to find whether a file is an executable in node.js -

i looking platform independent (win, mac, linux) way of finding whether file executable or not. following doesn't work me (not on linux) -

var spawn = require("child_process").spawn; var proc = spawn("whatever file"); proc.stderr.on('data', function (data) {   if (/^execvp\(\)/.test(data)) {     console.log('failed start child process.');   } }); 

i advise against executing file way test whether it's executable. if don't know file is, don't run it! security , general damage nightmare. analogous testing whether vial of clear liquid poison drinking it.

step 1: read it's metadata via stat

on posix (linux, mac, bsd), use fs.stat examine mode field check various permutations executable.

step 2: read beginning of file data , guess type

you can run file utility on it, use database of magic numbers , other heuristics guess file type.

windows

in terms of platform independent, afaik functionality isn't similar enough on windows there reliable windows equivalent of above posix-oriented techniques. windows filesystems , filetypes different, think if want work, you'll need separate implementation handle windows (and other me suggest how implement on windows).