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diff --git a/node_modules/flagged-respawn/README.md b/node_modules/flagged-respawn/README.md new file mode 100644 index 000000000..a431fe36e --- /dev/null +++ b/node_modules/flagged-respawn/README.md @@ -0,0 +1,58 @@ +# flagged-respawn [](http://travis-ci.org/js-cli/js-flagged-respawn) +> A tool for respawning node binaries when special flags are present. + +[](https://nodei.co/npm/flagged-respawn/) + +## What is it? + +Say you wrote a command line tool that runs arbitrary javascript (e.g. task runner, test framework, etc). For the sake of discussion, let's pretend it's a testing harness you've named `testify`. + +Everything is going splendidly until one day you decide to test some code that relies on a feature behind a v8 flag in node (`--harmony`, for example). Without much thought, you run `testify --harmony spec tests.js`. + +It doesn't work. After digging around for a bit, you realize this produces a [`process.argv`](http://nodejs.org/docs/latest/api/process.html#process_process_argv) of: + +`['node', '/usr/local/bin/test', '--harmony', 'spec', 'tests.js']` + +Crap. The `--harmony` flag is in the wrong place! It should be applied to the **node** command, not our binary. What we actually wanted was this: + +`['node', '--harmony', '/usr/local/bin/test', 'spec', 'tests.js']` + +Flagged-respawn fixes this problem and handles all the edge cases respawning creates, such as: +- Providing a method to determine if a respawn is needed. +- Piping stderr/stdout from the child into the parent. +- Making the parent process exit with the same code as the child. +- If the child is killed, making the parent exit with the same signal. + +To see it in action, clone this repository and run `npm install` / `npm run respawn` / `npm run nospawn`. + +## Sample Usage + +```js +#!/usr/bin/env node + +const flaggedRespawn = require('flagged-respawn'); + +// get a list of all possible v8 flags for the running version of node +const v8flags = require('v8flags').fetch(); + +flaggedRespawn(v8flags, process.argv, function (ready, child) { + if (ready) { + console.log('Running!'); + // your cli code here + } else { + console.log('Special flags found, respawning.'); + } + if (process.pid !== child.pid) { + console.log('Respawned to PID:', child.pid); + } +}); + +``` + +## Release History + +* 2016-03-22 - v0.3.2 - fix issue with v8 flags values being dropped +* 2014-09-12 - v0.3.1 - use `{ stdio: 'inherit' }` for spawn to maintain colors +* 2014-09-11 - v0.3.0 - for real this time +* 2014-09-11 - v0.2.0 - cleanup +* 2014-09-04 - v0.1.1 - initial release |