If you ever encounter Firefox saying

Error code: ssl_error_rx_record_too_long

or Chrome / Chromium / Webkit complaining with

Error 107 (net::ERR_SSL_PROTOCOL_ERROR): SSL protocol error.

and you just reconfigured your Apache webserver, adding a new VirtualHost on port 443, make sure you didn't forget

SSLEnable on

in the VirtualHost block. Otherwise Apache tries to serve non-encrypted content over the SSL-port and web browsers don't like that and don't produce helpful error messages. Nothing in the Apache log files either...

posted at: 00:00 | path: /unix | permanent link to this entry

DraftSight is a pretty complete 2D CAD product which can read and write DXF and DWG files. It works great in a VirtualBox virtual-machine in Linux, but I rather like to run things natively if possible. Installing it in my existing Wine prefix worked, but trying to run it gave me the following error: Runtime Error! An application has made an attempt to load the C runtime library incorrectly. Please contact the application's support team for more information. Therefore I tried a clean install in a new Wine prefix using the following commands (using some hints from here):

export WINEPREFIX=$HOME/.winedraft
wget -O $WINEPREFIX/winetricks http://www.kegel.com/wine/winetricks
sh $WINEPREFIX/winetricks vcrun2005
chmod -R u-w $WINEPREFIX/drive_c/windows/winsxs
# execute the downloaded installation package
# http://www.3ds.com/products/draftsight/download-draftsight/
wine Downloads/DraftSight.exe
# You've to do a custome installation, otherwise the 'Install'
# button doesn't work

To launch (or use the installed menu link):

WINEPREFIX=$HOME/.winedraft wine $HOME/.winedraft/drive_c/P*/D*/D*/bin/DraftSight.exe

And that's it. Wine version 1.0.1, DraftSight version 10.7.400. The process was tested with Debian/Squeeze as of October 2010, but should also work with Ubuntu.

posted at: 00:00 | path: /unix | permanent link to this entry

A very handy way to estimate the on-disk size of your databases in PostgreSQL:

> SELECT datname,pg_size_pretty(pg_database_size(datname)) FROM pg_database;
    datname    | pg_size_pretty
---------------+----------------
 template1     | 4144 kB
 template0     | 4144 kB

And the same for individual tables:

> SELECT tablename,pg_size_pretty(pg_total_relation_size(tablename))
    FROM pg_tables WHERE schemaname NOT IN ('information_schema','pg_catalog');

         tablename          | pg_size_pretty
----------------------------+----------------
 django_content_type        | 40 kB
 django_session             | 152 kB
 django_site                | 24 kB

Now go and bug your application developers to save your resources.

posted at: 00:00 | path: /unix | permanent link to this entry