php chmod function changes file mode
When we operate files, we often use the chmod function to change the operation permissions of the specified directory.
Attributes
(in PHP 4, PHP 5)
With chmod - change the file mode
Description
Boolean attribute (character string $filename, int $mode)
Attempts to change the mode of the specified file to the provided mode.
Parameters
File name
File path.
Mode
Please note that mode is not automatically assumed to be an octal value, so strings (such as "grams + watts") will not work correctly. To ensure expected operation, you need to prefix the mode with zero ( 0 ):
chmod("/somedir/somefile", 755); // decimal; probably incorrect
chmod("/somedir/somefile" , "u+rwx,go+rx"); // string; incorrect
chmod("/somedir/somefile", 0755); // octal; correct value of mode
?>
The mode parameter contains three The octal number component specifies the owner of the access restriction; the owner of the user group is in the same order as everyone else in that order. A component can be calculated, adding the necessary permissions to this target user group. Number 1 means you granted execution rights, number 2 means you granted the file writeability, and number 4 meant you granted the file readability. These numbers were purchased to specify the rights required. You can also read more about the modes 'Man1Attribute' and 'Man2Attribute' on Unix systems.
// Read and write for owner, nothing for everybody else
chmod("/somedir/somefile", 0600);
// Read and write for owner, read for everybody else
chmod(" /somedir/somefile", 0644);
// Everything for owner, read and execute for others
chmod("/somedir/somefile", 0755);
// Everything for owner, read and execute for owner's group
chmod("/somedir/somefile", 0750);
?>
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