vibol.hou » Snippets

Uninstalling MacPorts

vibol — Sat, 19 Sep 2009 23:07:44 +0000

Having upgraded to Snow Leopard, I wanted to wipe out my MacPorts installation and start clean. I’ve had tons of stuff installed and updated from the past (three versions of each port, in fact). Here’s how to uninstall MacPorts.

The first step is to uninstall all the installed ports:

1	sudo port -f uninstall installed

Then remove any trace files lingering about:

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sudo rm -rf /opt/local \
/Applications/MacPorts \
/Applications/DarwinPorts \
/Library/Tcl/macports1.0 \
/Library/Tcl/darwinports1.0 \
/Library/LaunchDaemons/org.macports.* \
/Library/StartupItems/DarwinPortsStartup \
/Library/Receipts/MacPorts*.pkg \
/Library/Receipts/DarwinPorts*.pkg \
~/.macports

Three steps to uninstalling MySQL on Mac OS X

vibol — Sat, 19 Sep 2009 23:04:55 +0000

Here are three simple steps to uninstall the MySQL installation provided by MySQL.com. You should take care with these commands since a typo can obliterate portions of your OS, requiring a reinstall. If you’re comfortable with shell commands and understand what’s being done, here are the commands:

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sudo rm -rf "/usr/local/mysql*"
sudo rm -rf "/Library/StartupItems/MySQLCOM/"
Go to System Preferences... > ctrl-click the MySQL icon and remove it.

How to find total file size in Linux

vibol — Mon, 07 Sep 2009 19:04:23 +0000

DOS sums up the sizes of all the files it lists when using the dir command, but Linux ls does not. Here’s an awk script that will calculate that information.

1	ls -la [filenames] \| awk '{ sum += $4 } END { print sum }'

An easier command (thanks Sunny):

1	du -hs * --total

Mass renaming files in Linux

vibol — Thu, 13 Sep 2007 00:35:39 +0000

1	ls -d .ext \| sed 's/$.$.ext$/mv "&" "\1.newext"/' \| sh

Explanation here: Mass renaming with Linux shell

Code folding in VIM 6.0+

vibol — Thu, 16 Nov 2006 20:44:00 +0000

Here’s a neat little feature I’ve just been introduced to. After coding in VIM for so many years, one might think I’d know these things, but as it turns out, there’s a lot of features in VIM I’m not using. This one, however, will likely be a time-saver. There are a number of different code folding methods available in VIM (:help folding). I use the marker method by including this in my .vimrc file:

set foldmethod=marker

I can then use the following commands from command mode (not colon mode):

At the beginning of a function fragment, you can type ‘zfap’ to create a fold; this should add some {{{ }}} tags around your code in the comment of choice for the language you’re coding in.
You can type ‘zo’ to open a fold, or I can just hit the right arrow key on the folded code marker.
You can type ‘zc’ to close a fold.
You can type ‘zr’ to open all folds.
You can type ‘zm’ to close all folds.

More commands are available in :help folding.

Forcing an SSL Redirect in Apache

vibol — Tue, 14 Nov 2006 09:09:23 +0000

If you’ve ever needed to ensure that users are accessing a folder using SSL, you can use the following mod_rewrite snippet to achieve this:

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}

ExternalInterface, Internet Explorer and Callbacks

vibol — Wed, 16 Aug 2006 22:48:42 +0000

Whatever you do, don’t create callbacks named ‘stop’ or ‘play’ via:

ExternalInterface.addCallback(“play”, null, thisFunc);
ExternalInterface.addCallback(“stop”, null, thatFunc);

Internet Explorer will choke a most horrible script execution error. Having a broken Internet Explorer script debugger didn’t help much either. Firefox showed no problems with this terminology.

Rebuild RRDTool when upgrading cPanel’s Perl

vibol — Sat, 10 Jun 2006 22:30:01 +0000

If you’ve upgraded Perl in cPanel, you need to make sure you’ve got an up-to-date build of rrdtool or stats will not run properly on the server. To do this, run:

/scripts/rrdtoolinstall

If there is no output, you will have to manual edit the file and comment out the version comparison to force the rebuild. You have a bad build if the following error occurs when running /scripts/runstatsonce:

root@system [~]# /scripts/runstatsonce
This script requires cPanel 6.4.2 Build 11+
/usr/bin/perl: relocation error: /usr/local/cpanel/3rdparty/lib/perl/auto/RRDs/RRDs.so: undefined symbol: Perl_Gthr_key_ptr
/usr/bin/perl: relocation error: /usr/local/cpanel/3rdparty/lib/perl/auto/RRDs/RRDs.so: undefined symbol: Perl_Gthr_key_ptr