#15438 [Com]: include_once fails when comparing output to a value

ID: 15438 Comment by: m dot maika at charter dot net Reported By: michael at gamepoint dot net Status: Verified Bug Type: Scripting Engine problem Operating System: FreeBSD/Linux PHP Version: 4CVS-2002-10-14 New Comment: I'm think I know the cause, don't know the fix though. From reading and trying the examples it seems to be a precedence problem. include_once is running on the return value of the boolean operation. Similar to the reason why this doesn't work: $i=0; while ($row = mysql_fetch_object($result) && $i <= 10){ There, $row would be a true/false value because the && operator has a higher precedence than = and is executed first. I'm almost positive that this is the reason that include_once is failing when doing the comparison. Here you can see an example: ====t.php==== <?php if (include_once('s.php')==true){ echo 'It was included'; } ?> ============== ====s.php===== <?php echo 'This file should be included'; ?> ============== (Name file file 1, no extension) ====1========= <?php echo 'This file is included, when it was never mentioned.'; ?> ============== Results of running: [kicken@dell ~]$ php -q t.php This file gets included, when it was never mentionedIt was included All look at the php source, but I don't have high hopes for figure out how to fix it. Thought I'd mention this fact though incase anyone does know how to fix it. Tested on: PHP 4.3.0 (cgi), Copyright (c) 1997-2002 The PHP Group Zend Engine v1.3.0, Copyright (c) 1998-2002 Zend Technologies and PHP 4.3.2-RC1 (cli) (built: Apr 7 2003 18:50:44) Copyright (c) 1997-2003 The PHP Group Zend Engine v1.3.0, Copyright (c) 1998-2003 Zend Technologies Previous Comments: ------------------------------------------------------------------------ [2002-12-10 11:16:28] rogierbiba at hotmail dot com Because michael did mention this bug again... mfisher already did describe what happens when you use var_dump(include_once("someinclude.inc")) twice. So what's only left is the weird behaviour from the if(include_once("test.php") == false) or == true. when adding a few ()'s it works as expected. if((include_once("test.php"))== $bool){ echo("file test.php included"); } when $bool is 'true', it will echo the line, if $bool is 'false' it will not echo the line. if the file is not found it will produce a warning, and it will display the line when $bool is 'false'. In any case, adding the () around the include() will make the strange Warning: Failed opening '' for inclusion, or Warning: Failed opening '1' for inclusion, go away. ------------------------------------------------------------------------ [2002-12-09 06:25:34] andi@php.net I still don't understand what the problem is. includee() and friends are supposed to return whatever you return from within the included file. It's not supposed to return true or false. If you have a concrete reproducing script which doesn't work the way I mentioned please post it and email it to me (andi@zend.com) ------------------------------------------------------------------------ [2002-10-14 17:51:04] mfischer@php.net > Updated Version The include*/require* functions are a bit inconsistent. In the simple tests done, the filename printed after "Running" is the statement included in the source and executed by PHP, e.g. var_dump(require("file2include")); Every script ran exeutes the same statement twice in a row. First tests done by including the following: <?php echo "File got included\n"; ?> --> Running include.php File got included int(1) File got included int(1) --> Running include_once.php File got included int(1) bool(true) --> Running require.php File got included UNKNOWN:0 File got included UNKNOWN:0 --> Running require_once.php File got included int(1) bool(true) Same tests ran with: <?php echo "File got included\n"; return "Returning a string"; ?> --> Running include.php File got included string(18) "Returning a string" File got included string(18) "Returning a string" --> Running include_once.php File got included string(18) "Returning a string" bool(true) --> Running require.php File got included UNKNOWN:0 File got included UNKNOWN:0 --> Running require_once.php File got included string(18) "Returning a string" bool(true) ------------------------------------------------------------------------ [2002-10-08 06:29:23] cynic@php.net confirmed with 4.4.0-dev (cli)/ ZE 1.4.0. i'm including a repro recipe # This is a shell archive. Save it in a file, remove anything before # this line, and then unpack it by entering "sh file". Note, it may # create directories; files and directories will be owned by you and # have default permissions. # # This archive contains: # # foo.php # bar.inc # echo x - foo.php sed 's/^X//' >foo.php << 'END-of-foo.php' X#!/usr/bin/env php X<? X X if (include('bar.inc') == true) { X print "1. ok\n"; X } X X if (true == include('bar.inc')) { X print "2. ok\n"; X } X X $rv = include('bar.inc'); X if (true == $rv) { X print "3. ok\n"; X } END-of-foo.php echo x - bar.inc sed 's/^X//' >bar.inc << 'END-of-bar.inc' X<? X print "Hello world\n"; X END-of-bar.inc exit ------------------------------------------------------------------------ [2002-10-08 06:02:46] michael at gamepoint dot net I already forgot about this bug, but received the email today that this was considered bugus. Well i'm surprised, and tested it a few times more (with a newer php version), and i'm still convinced that this is a bug. A few new examples: <? if( include("include.txt") == true ) { print "File included\n"; } ?> The code above returns this fatal error: Warning: Failed opening '1' for inclusion (include_path='.:/usr/local/lib/php') in /usr/local/apache/htdocs/test.php on line 2 And now i do it the longer way: <? $status = include("include.txt"); if( $status == true ) { printf("File included!\n"); } ?> Works perfectly And another way that works: <? if( true == include("include.txt") ) { print "File included\n"; } ?> The problem really seems what derick@php.net said, a scripting engine bug. PS. Your reply about me asking a support question here is rather weird to me, i was just reporting a bug.. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/15438 -- Edit this bug report at http://bugs.php.net/?id=15438&edit=1