index.js

// thanks @krisselden for explaining the difference between win32 & unix FS's
// that manifest in this scenario

var fs = require('fs');
var file = 'output.txt';

fs.writeFileSync(file, 'first file');

var bufferA = new Buffer(256);
var bufferB = new Buffer(256);

var a = fs.openSync(file, 'r');

fs.unlinkSync(file);
fs.writeFileSync(file, 'second file');

var b = fs.openSync(file, 'r');

// thanks @krisselden for fixing my output
aBytesRead = fs.readSync(a, bufferA, 0, 20, 'utf-8');
bBytesRead = fs.readSync(b, bufferB, 0, 20, 'utf-8');

console.log('a', bufferA.toString('utf-8', 0, aBytesRead));
console.log('b', bufferB.toString('utf-8', 0, bBytesRead));

// On posix we will get:
//  first file
//  second file

// On win32 we should explode while doing the second writeFileSync loc:15
// as unlinking allows shared delete (via libuv) but not writing to a file 
// named the same as one that is unlinked, if the unlinked file still has open
// file descriptors

https://github.com/joyent/libuv/blob/master/src/win/fs.c#L426-L432

although https://github.com/joyent/libuv/blob/master/src/win/fs.c#L426-L432 claims to match unix semantics, it does so in many scenarios, but not the one demonstrated above.

I do not believe it to be possible to match this scenario, but maybe someone with more win32 chops can correct me.