103 lines
2.0 KiB
Markdown
103 lines
2.0 KiB
Markdown
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@license Apache-2.0
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Copyright (c) 2018 The Stdlib Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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-->
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# Standard Error
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> [Standard error][standard-streams].
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<section class="usage">
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## Usage
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```javascript
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var stderr = require( '@stdlib/streams/node/stderr' );
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```
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#### stderr
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[Standard error][standard-streams] as a [Writable stream][writable-stream].
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```javascript
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// Write to the terminal...
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stderr.write( 'Oh no!', 'utf8' );
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// e.g., => 'Oh no!'
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```
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</section>
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<!-- /.usage -->
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<section class="notes">
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## Notes
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- Unlike other streams, `stderr` can **never** be closed and, thus, never emits a `'finish'` event.
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- Although rare, writes can block when output is redirected to a file.
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</section>
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<!-- /.notes -->
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<section class="examples">
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## Examples
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<!-- run-disable -->
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<!-- eslint no-undef: "error" -->
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```javascript
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var proc = require( 'process' );
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var stdin = require( '@stdlib/streams/node/stdin' );
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var stderr = require( '@stdlib/streams/node/stderr' );
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// Set the encoding:
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stdin.setEncoding( 'utf8' );
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// Create an echo stream:
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stdin.pipe( stderr );
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// Push data to `stdin`:
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stdin.push( 'beep' );
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stdin.push( ' ' );
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stdin.push( 'boop' );
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stdin.push( '\n' );
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// End the stream:
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stdin.push( null );
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// Ensure the process closes:
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setTimeout( proc.exit, 1000 );
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```
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</section>
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<!-- /.examples -->
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<section class="links">
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[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
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[writable-stream]: https://nodejs.org/api/stream.html#stream_class_stream_writable
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</section>
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<!-- /.links -->
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