file_exists gives a misleading error message if
open_basedir is in effect.

Example:

<?php
error_reporting(E_ALL);

# We have:
# open_basedir = /var/www/htdocs/site-com-prod:/var/www/htdocs/site-com-test:/usr/local/phpwiki

// get $filename from parameters

if (file_exists($filename)) {
    print "The file $filename exists";
} else {
    print "The file $filename does not exist";
}

?>

Results:

The following give no problem, just the 'does not exist' result:

$filename = '/var/www/htdocs/site-com-prod/i_dont_exist.txt';
$filename = '/var/www/htdocs/site-com-test/i_dont_exist.txt';
$filename = '/usr/local/phpwiki-1.3.4';

Now we try something outsid of the open_basedir path set:

$filename = '/etc/passwd';

We get:

PHP Warning:  file_exists() [<a href='http://www.php.net/function.file-exists'>function.file-exists</a>]: open_basedir restriction in effect. File(/etc/passwd) is not within the allowed path(s): (/var/www/htdocs/site-com-prod) in /usr/local/phpwiki-1.3.4/test.php on line 12


Clearly, the open_basedir path indicated by file_exists() in this error message is wrong & confusing.