is tiny nodejs wrapper around altered version of lsof binary included in Mac OS X. This binary will only analyze regular files and is much faster than the original bundled with the os. More information can be found in the mac-lsof-regular-files-only repository. This library works only on Mac OS X.
#Usage
npm install lsof-mac-fast
Then you can use it like this:
var fastLsof = require('lsof-mac-fast');
var filesToCheck = ['/tmp/doc.docx', '/tmp/sheet.xlsx']; // or [] to analyze all file descriptors currently open
fastLsof.lsof(filesToCheck, function(err, stdout, stderr) { ... do something useful with the result ... })