posix_access
(PHP 5 >= 5.1.0, PHP 7)
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_ctermid →
? 1997–2017 The PHP Documentation GroupLicensed under the Creative Commons Attribution License v3.0 or later.
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