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| <html lang="en"> |
| |
| <head> |
| <link rel="stylesheet" type="text/css" href="../stylesheets/style.css"> |
| <title>Truncate Task</title> |
| </head> |
| |
| <body> |
| |
| <h2 id="touch">Truncate</h2> |
| <p><em>Since Apache Ant 1.7.1</em></p> |
| <h3>Description</h3> |
| |
| <p>Set the length of one or more files, as the <code>truncate</code> Unix function or GNU |
| utility. In addition to working with a single file, this Task can also work |
| on <a href="../Types/resources.html">resources</a> and resource collections.</p> |
| |
| <h3>Parameters</h3> |
| <table class="attr"> |
| <tr> |
| <th scope="col">Attribute</th> |
| <th scope="col">Description</th> |
| <th scope="col">Required</th> |
| </tr> |
| <tr> |
| <td>file</td> |
| <td>The name of the file.</td> |
| <td>Unless a nested resource collection element has been specified</td> |
| </tr> |
| <tr> |
| <td>length</td> |
| <td>Specifies the new file length (in bytes) to set. The following suffixes are supported: |
| <ul> |
| <li><q>K</q> : Kilobytes (1024 bytes)</li> |
| <li><q>M</q> : Megabytes (1024 K)</li> |
| <li><q>G</q> : Gigabytes (1024 M)</li> |
| <li><q>T</q> : Terabytes (1024 G)</li> |
| <li><q>P</q> : Petabytes (1024 T)</li> |
| </ul> |
| </td> |
| <td rowspan="2">At most one of these; omitting both implies <var>length</var>=<q>0</q> |
| </td> |
| </tr> |
| <tr> |
| <td>adjust</td> |
| <td class="left">Specifies the number of bytes (and positive/negative direction) by which to |
| adjust file lengths. The same suffixes are supported for this attribute as for |
| the <var>length</var> attribute. |
| </td> |
| </tr> |
| <tr> |
| <td>create</td> |
| <td>Whether to create nonexistent files.</td> |
| <td>No; default <q>true</q></td> |
| </tr> |
| <tr> |
| <td>mkdirs</td> |
| <td>Whether to create nonexistent parent directories when creating new files.</td> |
| <td>No; default <q>false</q></td> |
| </tr> |
| </table> |
| <h3>Parameters specified as nested elements</h3> |
| <h4>any resource collection</h4> |
| |
| <p>You can use any number of nested resource collection elements to define the resources for this |
| task and refer to resources defined elsewhere. <strong>Note</strong>: resources passed to this task |
| are expected to be filesystem-based.</p> |
| |
| <h3>Examples</h3> |
| |
| <p>Set the length of file <samp>foo</samp> to zero.</p> |
| <pre><truncate file="foo"/></pre> |
| |
| <p>Set the length of file <samp>foo</samp> to 1 kilobyte (1024 bytes).</p> |
| <pre><truncate file="foo" length="1K"/></pre> |
| |
| <p>Adjust the length of file <samp>foo</samp> upward by 1 kilobyte.</p> |
| <pre><truncate file="foo" adjust="1K"/></pre> |
| |
| <p>Adjust the length of file <samp>foo</samp> downward by 1 megabyte.</p> |
| <pre><truncate file="foo" adjust="-1M"/></pre> |
| |
| </body> |
| </html> |
