From:             mpb dot mail at gmail dot com
Operating system: Linux/Irrelevant
PHP version:      Irrelevant
PHP Bug Type:     Documentation problem
Bug description:  socket_set_option code example is misleading

Description:
------------
On this page:

http://www.php.net/manual/en/function.socket-set-option.php

Example 2275. socket_set_option() example

The example is misleading.  To be useful, SO_REUSEADDR must be set before
bind.  However, socket_create_listen calls bind (internally) before
SO_REUSEADDR is set.

So, if you:

1) run the (modified) script (the Reproduce code)
2) connect (via another process, say a manual telnet)
3) (the script will exit after socket_accept)
4) then re-run the script

In step 4, socket_create_listen will fail, because SO_REUSEADDR is NOT set
when socket_create_listen is called.

So, basically, unless socket_create_listen *automatically* and *invisibly*
sets SO_REUSEADDR for us, we cannot meaningfully use SO_REUSEADDR in
combination with socket_create_listen.

Probably socket_create_listen should be extend with another (boolean)
parameter so that we can tell it whether or not to set SO_RESUEADDR.

But, at the very least the docs should be fixed.

Additionally, the logic is flawed.  On error, socket_get_option returns
NULL, and (NULL !== 0) is true, so the example prints "SO_REUSEADDR is set
on socket !", even though there is *no* socket!.

Additionally, the docs say that socket_get_option should return false on
error, but on my machine (PHP 5.2.3) it returns NULL.

That's a lot of bugs!

Reproduce code:
---------------
<?php
$socket = socket_create_listen(1223);
socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);

if (socket_get_option($socket, SOL_SOCKET, SO_REUSEADDR) !== 0) {
    echo 'SO_REUSEADDR is set on socket !' . PHP_EOL;
}

// I add the following line so we can actually connect.
socket_accept ($socket);

?> 

Expected result:
----------------
SO_REUSEADDR is set on socket !


Actual result:
--------------
PHP Warning:  socket_create_listen(): unable to bind to given adress [98]:
Address already in use in <snip>/test.php on line 2
PHP Warning:  socket_set_option() expects parameter 1 to be resource,
boolean given in <snip>/test.php on line 3
PHP Warning:  socket_get_option() expects parameter 1 to be resource,
boolean given in <snip>/test.php on line 5
SO_REUSEADDR is set on socket !
PHP Warning:  socket_accept() expects parameter 1 to be resource, boolean
given in <snip>/test.php on line 10


-- 
Edit bug report at http://bugs.php.net/?id=42343&edit=1
-- 
Try a CVS snapshot (PHP 4.4): 
http://bugs.php.net/fix.php?id=42343&r=trysnapshot44
Try a CVS snapshot (PHP 5.2): 
http://bugs.php.net/fix.php?id=42343&r=trysnapshot52
Try a CVS snapshot (PHP 6.0): 
http://bugs.php.net/fix.php?id=42343&r=trysnapshot60
Fixed in CVS:                 http://bugs.php.net/fix.php?id=42343&r=fixedcvs
Fixed in release:             
http://bugs.php.net/fix.php?id=42343&r=alreadyfixed
Need backtrace:               http://bugs.php.net/fix.php?id=42343&r=needtrace
Need Reproduce Script:        http://bugs.php.net/fix.php?id=42343&r=needscript
Try newer version:            http://bugs.php.net/fix.php?id=42343&r=oldversion
Not developer issue:          http://bugs.php.net/fix.php?id=42343&r=support
Expected behavior:            http://bugs.php.net/fix.php?id=42343&r=notwrong
Not enough info:              
http://bugs.php.net/fix.php?id=42343&r=notenoughinfo
Submitted twice:              
http://bugs.php.net/fix.php?id=42343&r=submittedtwice
register_globals:             http://bugs.php.net/fix.php?id=42343&r=globals
PHP 3 support discontinued:   http://bugs.php.net/fix.php?id=42343&r=php3
Daylight Savings:             http://bugs.php.net/fix.php?id=42343&r=dst
IIS Stability:                http://bugs.php.net/fix.php?id=42343&r=isapi
Install GNU Sed:              http://bugs.php.net/fix.php?id=42343&r=gnused
Floating point limitations:   http://bugs.php.net/fix.php?id=42343&r=float
No Zend Extensions:           http://bugs.php.net/fix.php?id=42343&r=nozend
MySQL Configuration Error:    http://bugs.php.net/fix.php?id=42343&r=mysqlcfg

Reply via email to