Determine accessibility of a file

POSIX Functions
posix_ctermid
POSIX Functions
PHP Manual

# posix_access

(PHP 5 >= 5.1.0)

posix_access — Determine accessibility of a file

### Description

bool posix_access ( string `$file` [, int `$mode` = POSIX_F_OK ] )

posix_access() checks the user's permission of a file.

### Parameters

`file`

  The name of the file to be tested.

`mode`

  A mask consisting of one or more of `POSIX_F_OK`, `POSIX_R_OK`, `POSIX_W_OK` and `POSIX_X_OK`.

  `POSIX_R_OK`, `POSIX_W_OK` and `POSIX_X_OK` request checking whether the file exists and has read, write and execute permissions, respectively. `POSIX_F_OK` just requests checking for the existence of the file.

### Return Values

Returns `TRUE` on success or `FALSE` on failure.

### Examples

Example #1 posix_access() example

This example will check if the $file is readable and writable, otherwise will print an error message.

`<?php
$file = 'some_file';
if (posix_access($file, POSIX_R_OK | POSIX_W_OK)) {
echo 'The file is readable and writable!';
} else {
$error = posix_get_last_error();
echo "Error $error: " . posix_strerror($error);
}
?>`

### Notes

> Note: When safe mode is enabled, PHP checks whether the files or directories being operated upon have the same UID (owner) as the script that is being executed.

### See Also

- posix_get_last_error() - Retrieve the error number set by the last posix function that failed
- posix_strerror() - Retrieve the system error message associated with the given errno

POSIX Functions
posix_ctermid
POSIX Functions
PHP Manual