50 lines
1.3 KiB
HTML
50 lines
1.3 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
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<html>
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<head>
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<meta name="generator" content="HTML Tidy, see www.w3.org">
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<meta http-equiv="Content-Type" content=
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"text/html; charset=utf-8">
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<title>Performance considerations</title>
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<LINK rel="stylesheet" type="text/css" href="../rzahg/ic.css">
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</HEAD>
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<body bgcolor="#FFFFFF">
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<!-- Java sync-link -->
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<SCRIPT LANGUAGE="Javascript" SRC="../rzahg/synch.js" TYPE="text/javascript"></SCRIPT>
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<h2>Performance considerations</h2>
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<p>The following tips can help improve performance when using <strong>qsh</strong>.</p>
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<ul>
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<li>Do not use command substitutions in the value of the <strong>
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PS1</strong> variable. This causes a new process to be started
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every time you press the <enter> key.<p></li>
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<li>Use input redirection instead of cat. For example, the
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following command:
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<pre>
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cat myfile | grep Hello
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</pre>
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<p>can be replaced with this command:</p>
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<pre>
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grep Hello < myfile
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</pre>
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</li>
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<li>Use built-in utilities whenever possible because they are run
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in the current process.<p></li>
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<li>Leave the <strong>SHELL</strong> variable unset. If a script
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file does not contain a "#!" on the first line, the script is run
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in the current activation of <strong>qsh</strong>.<p></li>
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</ul>
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</body>
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</html>
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