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PHP chmod() Function

< Complete PHP Filesystem Reference

Definition and Usage

The chmod() function changes permissions of the specified file.

Returns TRUE on success and FALSE on failure.

Syntax

chmod(file,mode)

Parameter Description
file Required. Specifies the file to check
mode Required. Specifies the new permissions.

The mode parameter consists of four numbers:

  • The first number is always zero
  • The second number specifies permissions for the owner
  • The third number specifies permissions for the owner's user group
  • The fourth number specifies permissions for everybody else

Possible values (to set multiple permissions, add up the following numbers):

  • 1 = execute permissions
  • 2 = write permissions
  • 4 = read permissions

Example

<?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's group
chmod("test.txt",0740);
?>
< Complete PHP Filesystem Reference