49 lines
1.6 KiB
HTML
49 lines
1.6 KiB
HTML
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---
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layout: page
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author: Alessandro Luini
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category-page: advanced
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category-title: Advanced commands
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tags: translate
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title: tr
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---
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<p> tr is a command in Unix-like operating systems. It is an abbreviation of
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translate or transliterate, indicating its operation of replacing or removing
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specific characters in its input data set.</p>
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<h3>How to use</h3>
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<p> The utility reads a byte stream from its standard input and writes the
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result to the standard output. As arguments, it takes two sets of
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characters (generally of the same length), and replaces occurrences of
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the characters in the first set with the corresponding elements from the
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second set. For example,
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</p>
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<pre> <code>tr 'abcd' 'jkmn'</code></pre>
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<p> maps all characters a to j, b to k, c to m, and d to n.</p>
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<p> The character set may be abbreviated by using character ranges. The
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previous example could be written: </p>
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<pre> tr 'a-d' 'jkmn' </pre>
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<h3>Flags</h3>
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<ul>
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<li><h4> -s:</h4> The s flag causes tr to compress sequences of identical
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adjacent characters in its output to a single token.
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<pre> tr -s '\n'</pre>
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replaces sequences of one or more newline characters with a single
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newline.</li>
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<li><h4> -d</h4>:The d flag causes tr to delete all tokens of the specified
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set of characters from its input. In this case, only a single character
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set argument is used. The following command removes carriage return
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characters.
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<pre>tr -d '\r'</pre>
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</li>
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