72 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
# arch [![travis][travis-image]][travis-url] [![npm][npm-image]][npm-url] [![downloads][downloads-image]][downloads-url] [![javascript style guide][standard-image]][standard-url]
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[travis-image]: https://img.shields.io/travis/feross/arch/master.svg
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[travis-url]: https://travis-ci.org/feross/arch
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[npm-image]: https://img.shields.io/npm/v/arch.svg
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[npm-url]: https://npmjs.org/package/arch
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[downloads-image]: https://img.shields.io/npm/dm/arch.svg
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[downloads-url]: https://npmjs.org/package/arch
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[standard-image]: https://img.shields.io/badge/code_style-standard-brightgreen.svg
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[standard-url]: https://standardjs.com
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### Better `os.arch()` for node and the browser -- detect OS architecture
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[](https://saucelabs.com/u/arch2)
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This module is used by [WebTorrent Desktop](http://webtorrent.io/desktop) to
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determine if the user is on a 32-bit vs. 64-bit operating system to offer the
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right app installer.
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In Node.js, the `os.arch()` method (and `process.arch` property) returns a string
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identifying the operating system CPU architecture **for which the Node.js binary
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was compiled**.
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This is not the same as the **operating system CPU architecture**. For example,
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you can run Node.js 32-bit on a 64-bit OS. In that situation, `os.arch()` will
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return a misleading 'x86' (32-bit) value, instead of 'x64' (64-bit).
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Use this package to get the actual operating system CPU architecture.
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**BONUS: This package works in the browser too.**
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## install
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```
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npm install arch
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```
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## usage
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```js
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var arch = require('arch')
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console.log(arch()) // always returns 'x64' or 'x86'
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```
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In the browser, there is no spec that defines where this information lives, so we
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check all known locations including `navigator.userAgent`, `navigator.platform`,
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and `navigator.cpuClass` to make a best guess.
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If there is no *affirmative indication* that the architecture is 64-bit, then
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32-bit will be assumed. This makes this package perfect for determining what
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installer executable to offer to desktop app users. If there is ambiguity, then
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the user will get the 32-bit installer, which will work fine even for a user with
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a 64-bit OS.
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For reference, `x64` means 64-bit and `x86` means 32-bit.
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Here is some history behind these naming conventions:
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- https://en.wikipedia.org/wiki/X86
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- https://en.wikipedia.org/wiki/IA-32
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- https://en.wikipedia.org/wiki/X86-64
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## Node.js proposal - `os.sysarch()`
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Note: There is
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[a proposal](https://github.com/nodejs/node-v0.x-archive/issues/2862#issuecomment-103942051)
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to add this functionality to Node.js as `os.sysarch()`.
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## license
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MIT. Copyright (c) [Feross Aboukhadijeh](http://feross.org).
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