Checkout only changed files from TFS using gulp and gulp-changed.

TFSCheckout.js

var fs = require('fs');

// ignore missing file error
function fsOperationFailed(stream, sourceFile, err) {
    if (err) {
        if (err.code !== 'ENOENT') {
            stream.emit('error', new gutil.PluginError('gulp-changed', err, {
                fileName: sourceFile.path
            }));
        }
        stream.push(sourceFile);
    }
    return err;
}

// Checkout the changed file.
function checkoutFile(stream, sourceFile, targetPath, cb){
    var exec = require('child_process').exec;
    exec('tf checkout ' + targetPath + ' /recursive /lock:none', function (error, stdout, stderr) {
        console.log('Checking out ' + stdout);
        stream.push(sourceFile);
        cb();
    });
}

exports.checkOutSingle = function(stream, cb, sourceFile, targetPath, targetFile){
    fs.stat(targetPath, function (err, targetStat) {
        if (!fsOperationFailed(stream, sourceFile, err)) {
            if (sourceFile.stat.mtime > targetStat.mtime) {
                return checkoutFile(stream, sourceFile, targetFile, cb);
            }
        }

        cb();
    });
}

// only checkout changed files
exports.checkChanged = function(stream, cb, sourceFile, targetPath){    
    fs.stat(targetPath, function (err, targetStat) {
        if (!fsOperationFailed(stream, sourceFile, err)) {
            if (sourceFile.stat.mtime > targetStat.mtime) {
                return checkoutFile(stream, sourceFile, targetPath, cb);
            }
        }

        cb();
    });
}

@loktar00 How do i use above functions in my gulp task, and what is "exports" is it a keyword ? when i paste above code in gulp.js how do I call that fuctions to checkout files on TFS. Please provide more info of how to use it, can you provide example or something ?