Archive for Notes
Debugging CGI Using ptkdb
Posted by: | Commentsptkdb is a graphical Perl debugger. To use it when debugging command line scripts is very straight forward. Just type in the command line:
perl -d:ptkdb script.pl
and you’re good to go.
However, using it to debug CGIs needs some tweaking to your CGI source. Replace the usual
#!/usr/bin/perlline at the top of the CGI script with this one:
#!/usr/bin/perl -d:ptkdb BEGIN {$ENV{DISPLAY} = "$ENV{REMOTE_ADDR}:0.0";}
Go to your browser and invoke your CGI and a debugger window should pop up.
Change Behavior of iTunes Arrows
Posted by: | CommentsStarting with iTunes 4.5, Apple implemented those little grey arrows next to the song title, artist, and album, which will take you to the corresponding match in the iTunes Music Store. To change the behavior of these arrows so that instead of going to the store, it will take you to your library instead, you can do either one of two ways:
- Hit option key when you click the arrow.
- Change it permamnently by executing this from the terminal:
defaults write com.apple.iTunes invertStoreLinks -bool YES
Make sure iTunes is not running when you execute this command.
Enable Safari Debug Menu
Posted by: | CommentsTo enable Safari Debug menu from the command line:
% defaults write \ com.apple.Safari IncludeDebugMenu 1
Make sure Safari is not running when you run this command.
Determine Disk Usage
Posted by: | CommentsThis command will show the number of KBs used for all non-hidden files and folders in the current directory:
du -sk * | sort -rn
Find By Contents
Posted by: | CommentsThis will recursively search all the files, with a certain filename pattern (in this case *.h) in a certain directory, that contains a certain text pattern in its contents (in this case ‘DeviceDriver’).
find . -name '*.h' -print0 \ | xargs -0 grep -n -e DeviceDriver
CGI To Display Module Documentation
Posted by: | CommentsHere’s a CGI to display a module’s POD. The module has to be in the $INC. This is great for providing documentation to internal modules.
# save this as showdoc.cgi #!/usr/local/bin/perl use strict; use Pod::Html; use CGI; use CGI::Carp qw(fatalsToBrowser); # Send out the header print "Content-type: text/html", "\n\n"; my $q = new CGI; my $module = $q->param('module'); require $module; $| = 1; chdir ("/tmp"); my $fullpath = $INC{$module} or die "$module not found"; pod2html("--infile=$fullpath", "--flush"); # Clean up the junk left by pod2html END { unlink("pod2html-dircache"); unlink("pod2html-itemcache"); }
To use this, say you want to view POD for Data::Dumper:
http://localhost/cgi-bin/showdoc.cgi?module=Data/Dumper.pm
crontab Format
Posted by: | Comments[I could never remember this so I'm putting it here.]
These are the fields of a crontab file:
a b c d e /full/path/to/script where a = minute (0-59), b = hour (0-23), c = day of the month (1-31), d = month of the year (1-12), e = day of the week (0-6 with 0=Sunday). * = every min, hour, day, etc. */10 = every 10 min, hour, day, etc.
Read A Text File
Posted by: | CommentsThis will open a text file and read it line by line. As it is, it will just print each line to the screen, so very much like the unix ‘cat’ command, but could very well do anything on the line just read by replacing the cout statement.
#include <fstream> #include <iostream> #include <string> void main() { string s; ifstream infile; infile.open("aaa.txt"); while(infile >> s) { cout << s << endl; } }
Create Skeleton Module
Posted by: | CommentsUse this to create a skeleton module:
h2xs -AXn Your::Module
stty Settings
Posted by: | CommentsThis is my stty setting (all in one line):
stty intr '^c' erase '^?' kill '^u' echoe \ echoctl echoke -ixany