set-blocking

What is set-blocking?

The set-blocking npm package is primarily used to control the blocking behavior of streams in Node.js. This can be particularly useful in scenarios where you need to ensure that stdout or stderr is fully drained before your process exits, especially in the context of CLI applications. The package provides a straightforward API to toggle the blocking behavior of these streams.

What are set-blocking's main functionalities?

Setting stream blocking

This code enables blocking on stdout and stderr, ensuring that all output is flushed to these streams before the process exits. This is particularly useful for CLI tools that output to the terminal and need to ensure that all output is displayed to the user before the process terminates.

require('set-blocking')(true);

Other packages similar to set-blocking

block-stream

The block-stream package provides functionality for creating streams that block until a certain number of bytes have been collected. While it serves a different purpose by focusing on the manipulation and control of stream data in blocks, it shares the concept of controlling stream behavior with set-blocking. However, set-blocking is specifically tailored for setting the blocking behavior of process output streams, making it more specialized for scenarios involving stdout or stderr.

end-of-stream

end-of-stream is a package that allows you to wait for the end of a stream (readable, writable, or duplex) and execute a callback. It is similar to set-blocking in the sense that both packages deal with stream behavior and ensuring certain conditions are met before proceeding. However, end-of-stream focuses on detecting the end of a stream, whereas set-blocking specifically enables or disables blocking behavior on stdout and stderr.

README

set-blocking

set blocking stdio and stderr ensuring that terminal output does not truncate.

const setBlocking = require('set-blocking')
setBlocking(true)
console.log(someLargeStringToOutput)

Historical Context/Word of Warning

This was created as a shim to address the bug discussed in node #6456. This bug crops up on newer versions of Node.js (0.12+), truncating terminal output.

You should be mindful of the side-effects caused by using set-blocking:

• if your module sets blocking to true, it will effect other modules consuming your library. In yargs we only call setBlocking(true) once we already know we are about to call process.exit(code).
• this patch will not apply to subprocesses spawned with isTTY = true, this is the default spawn() behavior.

License

ISC

Changelog

2.0.0 (2016-05-17)

Features

• add an isTTY check (#3) (66ce277)

BREAKING CHANGES

• stdio/stderr will not be set to blocking if isTTY === false

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