The is_readable() function in PHP used to check whether the specified file exists and is readable or not. The name of the file is sent as a parameter to the is_readable() function and it returns True if the file exists and is readable.
is_readable() function returns False for streams, for example, php://stdin.
is_readable() function can also be used with some URL wrappers such as file: // ,http:// ,ftp:// ,php:// in PHP 5.0.0.
Syntax:
is_readable($file)
Parameters Used:
The is_readable() function in PHP accepts only one parameter.
- file : It is a mandatory parameter which specifies the file.
Return Value:
It returns True if the file or directory specified exists and is readable otherwise it returns False.
Exceptions:
- An E_WARNING is emitted on failure.
- The result of this function are cached and therefore the clearstatcache() function is used to clear the cache.
Below programs illustrate the is_readable() function.
Program 1
<?php $myfile = "gfg.txt" ;
// checking whether file is readable or not if ( is_readable ( $myfile ))
{ echo '$myfile is readable' ;
} else { echo '$myfile is not readable' ;
} ?> |
Output:
gfg.txt is readable
Program 2
<?php $myfile = "gfg.txt" ;
// checking whether file is readable or not if ( is_readable ( $myfile ))
{ echo '$myfile is readable' ;
// displaying contents of the uploaded file
echo "Contents of the file are :\n" ;
readfile( $myfile );
} else { echo '$myfile is not readable' ;
} ?> |
Output:
gfg.txt is readable Contents of the file are : Portal for geeks!
Program 3
<?php $permissions = fileperms ( "gfg.txt" );
$permvalue = sprintf( "%o" , $permissions );
// Clearing the File Status Cache clearstatcache(); if ( is_readable ( "gfg.txt" ))
{ echo ("File is Readable
and File Permissions are : $permvalue )");
} else { echo ("File is Not Readable
and File Permissions are : $permvalue )");
} // Clearing the File Status Cache clearstatcache(); ?> |
Output:
File is Readable and File Permissions are : 0644
Related Article: PHP | is_writable() Function
Reference:
http://php.net/manual/en/function.is-readable.php