How to Use the touch() Function Together with chmod() to Adjust File Permissions?

gitbox 2025-09-09
<span class="hljs-meta"><?php
// This part is unrelated to the article content and can include some initialization code
date_default_timezone_set('Asia/Shanghai');
$logFile = __DIR__ . '/log.txt';
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    file_put_contents($logFile, "Log initialized\n");
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<p><span class="hljs-meta"><?php<br>
/**</p>
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<p>Title: How to Use the touch() Function Together with chmod() to Adjust File Permissions?</p>
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<p>In PHP, the touch() function is commonly used to create new files or update the modification time of existing files,</p>
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<p>while the chmod() function is used to set file access permissions. By combining the two, you can conveniently</p>
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<p>control file permissions at the moment of creation, ensuring files can be correctly read and written in your application.</p>
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<p>Example steps are as follows:<br>
*/</p>
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<p>// 1. Create a file using touch()<br>
$filePath = <strong>DIR</strong> . '/example.txt';<br>
if (touch($filePath)) {<br>
echo "File created or modification time updated: $filePath\n";<br>
} else {<br>
echo "Failed to create file\n";<br>
}</p>
<p>// 2. Set file permissions using chmod()<br>
// For example, set to 0644, which allows the owner to read/write and group/others to read<br>
if (chmod($filePath, 0644)) {<br>
echo "File permissions set to 0644\n";<br>
} else {<br>
echo "Failed to set file permissions\n";<br>
}</p>
<p>/**</p>
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<p>3. Notes:</p>
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<p>The permission parameter of chmod() is usually represented in octal, e.g., 0644, 0755.</p>
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<p>The actual effect of permissions depends on the operating system and the user under which PHP runs.</p>
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<p>On some systems, chmod() may fail if the PHP process lacks sufficient permissions.</p>
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<p>touch() can also update the access and modification times of existing files, not just create new files.</p>
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<p>Combining touch() and chmod() allows convenient initialization of files, such as log files,</p>
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<p>temporary files, or configuration files, ensuring their permissions comply with security policies.<br>
*/<br>
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<p data-is-last-node="" data-is-only-node=""><span class="hljs-meta"><?php<br>
// This part is also unrelated to the article content and can include end-of-script logging or cleanup<br>
file_put_contents($logFile, "Script execution completed\n", FILE_APPEND);<br>
?><br>
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