Beaver6813.com » Notes

PHP Compilation (Cannot find -lltdl)

Beaver6813 — Sat, 10 Jul 2010 18:15:10 +0000

When compiling PHP from source (in my case version 5.3.2) on CentOS 5.4 I kept getting the following error when trying to compile with mcrypt:

"/usr/bin/ld: cannot find -lltdl"

This seems to be due to a missing development library with the obscure name of libtool-ltdl-devel to fix this simply use:

yum install libtool-ltdl-devel

Which should include the package along with several dependencies.

libltdl3-dev

PHP Search and Replace Directory Recursively

Beaver6813 — Tue, 13 Apr 2010 16:04:11 +0000

On a message forum I regularily visit a member was having issues with code being placed in multiple files that he wanted to remove or change without having to edit each and every file manually. For this I created a search and replace function which will recursively search the directory and every file for a specific piece of code and will replace with whatever:

^?View Code PHP


$stringsearch = "texttosearchfor";
$dir = "./";
echo "Starting search for $stringsearch within directory $dir
";
        $listDir = array();
        if($handler = opendir($dir)) {
            while (($sub = readdir($handler)) !== FALSE) {
                if ($sub != "." &amp;&amp; $sub != ".." &amp;&amp; $sub != "Thumb.db") {
                    if(is_file($dir."/".$sub)) {
                        if(substr_count($sub,'.php'))
                            {
                            $getfilecontents = file_get_contents($dir."/".$sub);
                            if(substr_count($getfilecontents,$stringsearch)&gt;0)
                            {
                            $replacer = str_replace($stringsearch,$stringreplace,$getfilecontents);
                            // Let's make sure the file exists and is writable first.
                              if (is_writable($dir."/".$sub)) {
                                  if (!$handle = fopen($dir."/".$sub, 'w')) {
                                       echo "Cannot open file (".$dir."/".$sub.")";
                                       exit;
                                  }
                                  // Write $somecontent to our opened file.
                                  if (fwrite($handle, $replacer) === FALSE) {
                                      echo "Cannot write to file (".$dir."/".$sub.")";
                                      exit;
                                  }
                                  echo "Success, removed searched content from:"$dir."/".$sub."
";
                                  fclose($handle);
                              } else {
                                  echo "The file ".$dir."/".$sub" is not writable
";
                              }
                            }
                            }
                        $listDir[] = $sub;
                    }elseif(is_dir($dir."/".$sub)){
                        $listDir[$sub] = SearchandReplace($dir."/".$sub,$stringsearch,$stringreplace);
                    }
                }
            }
            closedir($handler);
        }
        return $listDir;
    }
?>

GoDaddy mod_rewrite Hell

Beaver6813 — Thu, 18 Mar 2010 13:17:58 +0000

Whilst trying to install a piece of software on a GoDaddy hosted account I noticed that mod_rewrite variables were simply not being passed to the correct pages. When digging a bit deeper I found that it was effectively ignoring extensions in URLs and just displaying the file with the extension. i.e. instead of having to enter:

www.example.com/advertise.php

you could instead type

www.example.com/advertise

And it would return the same file, which is good if for some unknown reason your file doesn’t have the correct extension, but its not exactly.. good..

After trawling Google for a while I found a post by Eric Faerber that solved the problem. The strange redirects were due to Apache MultiViews being enabled, disabling this by entering

Options -MultiViews

into the .htaccess file. Solved the problem, the simplest solutions are always the best!

Case of the missing/hidden IE8 Developer Tools window

Beaver6813 — Fri, 27 Nov 2009 14:14:02 +0000

Whilst working on a current project I was trying to get cross-browser compatability working nicely. However when I came to load up IE’s Developer Tools I found it was loading up the window but nothing was there! I’m running Windows 7 and this seems to be the only version of windows the problem is affecting:

The solution I found is actually very simple, right click on that hidden window thumbnail and click maximise. If that fails then you could always try a solution outlined on StackOverflow. The best solutions are often the most simple!!

[PHP] Get current time in milliseconds

Beaver6813 — Tue, 20 Oct 2009 17:59:31 +0000

I recently needed to get the current time in milliseconds, of course this can easily be retrieved using microtime() however I needed the entire number in digits, not in decimals with seconds seperately etc. Heres how:

^?View Code PHP

1
2
3

$timeparts = explode(" ",microtime());
$currenttime = bcadd(($timeparts[0]*1000),bcmul($timeparts[1],1000));
echo $currenttime;

NOTE: PHP5 is required for this function due to the improvements with microtime() and the bc math module is also required (as we’re dealing with large numbers, you can check if you have the module in phpinfo).

Bash, Bad Interpreter

Beaver6813 — Mon, 12 Oct 2009 15:42:42 +0000

I recently came across:

/bin/bash^M: bad interpreter: No such file or directory

When trying to run a bash script that someone else had edited. This most commonly happens on UNIX systems if the file has been edited on MS-DOS or Mac. The cure for this is to run a simple perl script:

^?View Code BASH

1 2	#!/usr/bin/perl -pi s/\n/\r\n/;

Save as unix2dos.pl, chmod +x unix2dos.pl and then run like:

./unix2dos.pl filetoconvert.txt

Simples!