ConFoo 2025

is_readable

(PHP 4, PHP 5, PHP 7, PHP 8)

is_readableTells whether a file exists and is readable

Description

is_readable(string $filename): bool

Tells whether a file exists and is readable.

Parameters

filename

Path to the file.

Return Values

Returns true if the file or directory specified by filename exists and is readable, false otherwise.

Errors/Exceptions

Upon failure, an E_WARNING is emitted.

Examples

Example #1 is_readable() example

<?php
$filename
= 'test.txt';
if (
is_readable($filename)) {
echo
'The file is readable';
} else {
echo
'The file is not readable';
}
?>

Notes

Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody').

Note: The results of this function are cached. See clearstatcache() for more details.

Tip

As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to Supported Protocols and Wrappers to determine which wrappers support stat() family of functionality.

Note:

The check is done using the real UID/GID instead of the effective one.

This function may return true for directories. Use is_dir() to distinguish file and directory.

See Also

add a note

User Contributed Notes 3 notes

up
9
jo at durchholz dot org
18 years ago
DrTebi at yahoo dot com is wrong. is_readable() checks whether you can do file_get_contents() or similar calls, no more, no less. If the location given returns a 500 or 403 error, you can still read() that (you'll simply get the error page), but it's still read()able. Using is_readable to check the validity of a URL is simply the wrong function.
up
1
pgl at yoyo dot org
15 years ago
Note that is_readable() will return false for streams, eg, php://stdin.
up
0
arikan134 at gmail dot com
8 years ago
is readable recursively. Check all sub directories and files readable
<?php
function is_readable_r($dir) {
if (
is_dir($dir)) {
if(
is_readable($dir)){
$objects = scandir($dir);
foreach (
$objects as $object) {
if (
$object != "." && $object != "..") {
if (!
is_readable_r($dir."/".$object)) return false;
else continue;
}
}
return
true;
}else{
return
false;
}

}else if(
file_exists($dir)){
return (
is_readable($dir));

}
}

?>
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