advanced: tr

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site/pages/cmd/advanced/tr.html

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