Commands by madd (2)

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List out classes in of all htmls in directory
Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box) WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

Insert a line at the top of a text file without sed or awk or bash loops
Yet another way to add a line at the top a of text file with the help of the tac command (reverse cat).

Reload all sysctl variables without reboot
Reload all defined kernel variables from /etc/sysctl.conf(if no parameter after -p is given) without the old myth "Ah, you'll need to reboot to apply those variables"...

fast access to any of your favorite directory.
example: -------------------------------------------------------------------------------------------- user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ addpi -------------------------------------------------------------------------------------------- Now that directory is in the list of fast access directories. You can switch to it anytime like this: -------------------------------------------------------------------------------------------- user@ubuntu:~$ pi internal` user@ubuntu:~/workspace/SVN/haystak-repos/trunk/internal/src$ -------------------------------------------------------------------------------------------- Please note the backquote ( the symbol that shares its key with ~ in the keyboard ) pi will switch you to that directory. To see the list of all fast access directories you have to say "cat ~/.pi"

List recorded formular fields of Firefox
When you fill a formular with Firefox, you see things you entered in previous formulars with same field names. This command list everything Firefox has registered. Using a "delete from", you can remove anoying Google queries, for example ;-)

know the current running shell (the true)
Return the current shell. It is better than print $SHELL which can sometimes return a false value.

Use default value if unassigned
Will use variable value (for variable $my_dir, in this case), an assign a default value if there is none.

use jq to validate and pretty-print json output
the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

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Convert text to lowercase
Usage: lower [STRING]...

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