What should I do if php cannot write files?

php cannot write files because the permissions are insufficient. The solution is to change the permissions of the specified file through the "chmod()" function in php. The syntax of this function is "chmod(file,mode)", and the parameters "mode" indicates new permissions.

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chmod() Function changes the specified file permission.

Returns TRUE if successful and FALSE if failed.

Syntax

chmod(file,mode)

Parameters

file required. Specifies the documents to be checked.

mode Required. Specify new permissions.

The mode parameter consists of 4 numbers:

The first number is usually 0

The second number specifies the owner's permissions

The third The first number specifies the permissions of the user group to which the owner belongs

The fourth number specifies the permissions of everyone else

Possible values ​​(if you need to set multiple permissions, please adjust the numbers below Total):

1 = Execute permission

2 = Write permission

4 = Read permission

Instance

<?php
// Read and write for owner, nothing for everybody else
chmod("test.txt",0600);
// Read and write for owner, read for everybody else
chmod("test.txt",0644);
// Everything for owner, read and execute for everybody else
chmod("test.txt",0755);
// Everything for owner, read for owner&#39;s group
chmod("test.txt",0740);
?>

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