[pmwiki-users] Transferring Wiki to another server

[Patrick R. Michaud]

On Mon, Nov 07, 2005 at 11:34:44AM -0600, Jonathan Scott Duff wrote:
> On Mon, Nov 07, 2005 at 12:20:09PM -0500, Bob Hazeldine wrote:
> > PHP on new server is 5.0.4
> > Pmwiki is 1.0.13
> 
> Looking at the code, I'd guess that your previous webserver had a more
> forgiving version of PHP installed as that line looks like it might
> need addslashes wrapped around part of it. I'm not sure, but here's a
> guess at what might work:
> 
> $text = preg_replace("/(\\\\*)\\\\\n/e",
>     "' '.str_repeat('<br />',strlen('".addslashes($1)."'))",$text);

I'm suspecting a PHP bug, or perhaps PHP is changing the way it
interprets the /e option (which would be Very Bad).

The original lines are:

  $text = preg_replace("/(\\\\*)\\\\\n/e",
    "' '.str_repeat('<br />',strlen('$1'))",$text);

which is supposed to find lines with two or more backslashes at
the end and generates <br /> tags for each.  In a normal preg_replace,
PHP sees the "/e" at the end and puts backslashes in front of any
quotes or backslashes it finds in the capture variable, so that
$1 should be "\\" and not "\".  However, the error message being
received is

    Fatal error: preg_replace() [function.preg-replace]: Failed evaluating 
    code: ' '.str_repeat('<br />',strlen('\')) in 
    /var/www/htdocs/pmwiki/pmwiki.php on line 821

which indicates that $1 received a single backslash.  Using
addslashes() doesn't help here, as the argument ($1) still
contains an unescaped backslash.

I think that several people have been able to run PmWiki on PHP 5.0.4
without any problems, so I'm guessing it's something about the PHP
instance on the server that's causing the problem here.

Pm