What is PHP chgrp() Function?
If you want to change the group of a file to another one, use chgrp() function. You can change the owner of a file if you are a superuser or running with root privilege. Other users may change the group of a file to any group of which that user is a member.
What is group in a file/directory? In Unix based operating system, the file control mechanism determines who can access a file/folder and what they can do with it. There are three type of users of each file/folder – owner (who own it), group (who share the same permission), and other (all the users except owner and group).
Syntax:
chgrp(filename, group)
Parameters:
The Function has 2 required parameters-
filename (Required): It is the path to the file or folder whose group you want to change.
group (Required): It is the new group to which you want to change. It could be a string or a number. When you mention name as a group, then it is a string. On the other hand, when you mention group id, then it is a number.
Return Values:
The function returns-
- TRUE – if it successfully changes the group.
- FALSE – if it can’t change the group.
Examples:
Example 1: Changing group using group name-
<?php
chown("docs/dl.pdf", "guest");
?>
Explanation:
The function changes group of the file dl.pdf to “guest”.
Example 2: Changing group using group id-
<?php
chgrp("docs/dl.pdf", 7);
?>
Explanation:
The function changes group of the file dl.pdf to the group whose group id is 7”.
Example 3: Changing group of the file with confirmation-
<?php
if (chgrp("docs/dl.pdf", "group")) {
echo "File group changed.";
} else {
echo "File group doesn't change.";
}
?>
Output:
File group changed.
Explanation:
Line 2: The function changes group of the file dl.pdf to “group” and returns TRUE and prints the message on line 3.
Best Practices on chgrp() Function:
- As the function returns TRUE on success and FALSE on failure, it is good practice to check the function’s success with conditional statement. Check example 3.
Notes on chgrp() Function:
- On Windows system, this function doesn’t work.
- This function can’t work on remote files as it can’t access the filesystem.
PHP Version Support:
PHP 4, PHP 5, PHP 7, PHP 8
Summary: PHP chgrp() Function
chgrp() is one of the filesystem functions in PHP which is used to change the group of a file. It helps you to manage your files and directories assigning proper ownership.