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.
is_readable
(PHP 4, PHP 5, PHP 7)
is_readable — Tells whether a file exists and is readable
Description
is_readable
( string
$filename
) : boolTells 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.
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';
}
?>
Errors/Exceptions
Upon failure, an E_WARNING is emitted.
Notes
Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody'). Safe mode limitations are not taken into account before PHP 5.1.5.
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
- is_writable() - Tells whether the filename is writable
- file_exists() - Checks whether a file or directory exists
- fgets() - Gets line from file pointer
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User Contributed Notes 4 notes
jo at durchholz dot org ¶
14 years ago
arikan134 at gmail dot com ¶
4 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));
}
}
?>
pgl at yoyo dot org ¶
10 years ago
Note that is_readable() will return false for streams, eg, php://stdin.
