init

node_modules/outpipe/readme.markdown

@@ -0,0 +1,117 @@
+# outpipe
+
+write output to a file through shell commands
+
+# purpose
+
+Suppose you have a tool like
+[watchify](https://npmjs.com/package/watchify)
+or [factor-bundle](https://npmjs.com/package/factor-bundle)
+that write to multiple files or write to the same file more than once.
+
+If you want to pipe the output of these tools to other programs, such as
+minification with the `uglify` command, it's very difficult! You might need to
+use the tool's API or use a separate command to watch for changes to the output
+files. Ick.
+
+You don't get the elegance of something like:
+
+``` sh
+$ browserify main.js | uglifyjs -cm | gzip > bundle.js.gz
+```
+
+Until now! With this library and a hypothetical version of watchify, you could
+do:
+
+``` sh
+$ watchify main.js -dv -o 'uglifyjs -cm | gzip > bundle.js.gz'
+```
+
+# example
+
+Here's a small watcher program that will just copy input files to a destination,
+but transforms can be applied along the way with shell pipes and redirects.
+
+``` js
+var outpipe = require('outpipe');
+var gaze = require('gaze');
+var fs = require('fs');
+
+var minimist = require('minimist');
+var argv = minimist(process.argv.slice(2), {
+    alias: { o: 'output' }
+});
+
+var file = argv._[0];
+gaze(file, function (err, w) {
+    w.on('changed', read);
+});
+read();
+
+function read () {
+    var r = fs.createReadStream(file);
+    r.pipe(outpipe(argv.output));
+}
+```
+
+We can run the program with a single output file:
+
+``` sh
+$ node watch.js input/x.js -o output/hmm.js
+```
+
+which just copies `x.js` to `output/hmm.js` whenever `x.js` changes.
+
+We could also run a minification step using the `uglify` command:
+
+``` sh
+$ node watch.js input/x.js -o 'uglifyjs -cm > output/wow.js'
+```
+
+or we can just print the size of the minified and gzipped output to stdout:
+
+``` sh
+$ node watch.js input/x.js -o 'uglifyjs -cm | gzip | wc -c'
+123
+```
+
+or we could write that size to a file:
+
+``` sh
+$ node watch.js input/x.js -o 'uglifyjs -cm | gzip | wc -c > size.txt'
+```
+
+# methods
+
+``` js
+var outpipe = require('outpipe')
+```
+
+## var w = outpipe(cmd, opts={})
+
+Return a writable stream `w` that will pipe output to the command string `cmd`.
+
+If `cmd` has no operators (`|` or `>`), it will write to a file.
+
+Otherwise, each command between pipes will be executed and output is written to
+a file if `>` is given.
+
+`opts` can be:
+
+* `opts.env` - an object mapping environment variables to their values or a
+`function (key) {}` that returns the values.
+
+stdout and stderr are forwarded to process.stdout and process.stderr if
+unhandled in the command.
+
+# install
+
+With [npm](https://npmjs.org) do:
+
+```
+npm install outpipe
+```
+
+# license
+
+MIT