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In PHP, you can use the chmod() function to modify the file read and write permissions. The function of this function is to change the permissions of the specified file; the syntax format is "chmod(file,mode)", and the parameter file specifies the Check the file, the parameter mode specifies new permissions.
The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer
php changes the read and write permissions of the file
<?php
// 所有者可读写，其他人没有任何权限
chmod("test.txt",0600);
// 所有者可读写，其他人可读
chmod("test.txt",0644);
// 所有者有所有权限，其他所有人可读和执行
chmod("test.txt",0755);
// 所有者有所有权限，所有者所在的组可读
chmod("test.txt",0740);
?>Related function description:
chmod() function changes the permissions of the specified file. Returns TRUE if successful, FALSE if failed.
Syntax
chmod(file,mode)
chmod will try to change the mode of the file specified by file to that given by mode.
| Parameters | Description |
|---|---|
| file | Required. Specifies the documents to be checked. |
| mode | Required. Specify new permissions. The mode parameter consists of 4 numbers:
Possible values (if you need to set multiple permissions, please set the following Total the numbers):
|
Note: mode will not be automatically treated as an octal value, and strings (such as "g w") cannot be used. To ensure correct operation, you need to add 0 in front of the mode:
<?php
chmod("/somedir/somefile", 755); // 十进制数，可能不对
chmod("/somedir/somefile", "u+rwx,go+rx"); // 字符串，不对
chmod("/somedir/somefile", 0755); // 八进制数，正确的 mode 值
?>The mode parameter contains three octal numbers in order to specify the owner, the owner's group, and everyone's access restrictions. Each part can be calculated by adding the required permissions. The number 1 makes the file executable, the number 2 makes the file writable, and the number 4 makes the file readable. Add these numbers to specify the required permissions.
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