readdir() in php not seeming to work - php

Question

I'm working on the following piece of code:
<?php
$dir=opendir("docs/recipes");
$files=array();
while (($file=readdir($dir)) !== false)
{
if ($file != "." and $file != ".." and $file != "index.php")
{
array_push($files, $file);
}
}
closedir($dir);
sort($files,SORT_STRING | SORT_FLAG_CASE);
print "<div class=\"blocktext\">";
foreach ($files as $file)
print "$file<br>";
print "</div>";
?>
I had this working on my raspberry pi web server, but I moved my server to arch linux, and it doesn't seem to be working. When I load the page, it spins but then the list of files is empty.
I have checked that httpd is running with systemd and because my webpages load. I know php is working because my phpinfo test page works.
In the folder containing this file, I have a symbolic link called docs, and I know the path is correct. I have all the files in the destination readable. This file is executable.
Is there something else I am missing?

Answer 1

Not necessarily a solution, but some help with good practices and a way to find what is happening on your script
<?php
// initialize variables first
$dir = false;
$files = array();
// assign the handler
$dir = opendir( "docs/recipes" );
// work only if necessary
if ( $dir !== false ) {
while ( ( $file = readdir( $dir ) ) !== false ) {
if ($file != "." and $file != ".." and $file != "index.php") {
array_push($files, $file);
}
}
closedir( $dir );
sort( $files,SORT_STRING | SORT_FLAG_CASE );
print "<div class=\"blocktext\">";
foreach ( $files as $file ) {
print "$file<br>";
}
print "</div>";
} else {
// get informed that something is wrong, print anything that helps you
echo( 'problems opening' );
exit( __FILE__.' '.__LINE__ );
}
?>

Answer 2

from php.net/readdir comes a warning: This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE.
you have not specified which version of PHP you are using, nor if it's installed/compiled locally. it would help. my guess is that you don't have all errors turned on, and readdir is catching one of those corner cases.
try this:
$cycle = true;
while ( $cycle !== false ) {
$file = readdir( $dir );
print ( "GOT a FILe or a FALSE:". $file ."br>" );
// do your stuff here
$cycle = $file;
}
then in php.ini set the errors to E_ALL. if using PHP >= 5.4 (i guess you are, since you're on arch :) you can fire up the built-in server, so all errors/logs/messages go straight to STDERR. just do a command from the folder where your index.php is located:
$ php -S <local ip>:<some port>
open as usual in the browser (or a curl, or whatever). output goes to browser, errors go straight to console, no middle-man to cover up any message.
this should enable you to catch the real problem. and/or, you can wrap it all up in a try-catch and see if something pops up.