Commands by dagh (1)

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Print current running shell, PID
works as well as echo $0, but also prints process id, which pts you're using. echo $SHELL doesn't always get updated when changing shells, so this is a better solution than that. Just one more variation on a theme.

restore the contents of a deleted file for which a descriptor is still available
Note that the file at the given path will have the contents of the (still) deleted file, but it is a new file with a new node number; in other words, this restores the data, but it does not actually "undelete" the old file. I posted a function declaration encapsulating this functionality to http://www.reddit.com/r/programming/comments/7yx6f/how_to_undelete_any_open_deleted_file_in_linux/c07sqwe (please excuse the crap formatting).

Do some learning...
compgen -c finds everything in your path.

Add fade in/out to first & last 25 frames of a video
Replace vid.mp4 with the path to your original video file, and out.mp4 to the path where you want to save the new file. To view the output first before saving, remove "-consumer avformat:out.mp4" from the end. Documentation for mlt framework and melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

fetch all revisions of a specific file in an SVN repository
Manages everything through one sed script instead of pipes of greps and awks. Quoting of shell variables is generally easier within a sed script.

Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

list files in 'hitlar' mode
Was playing with the shell. It struck to me, just by rearranging the parameters, i was able to remember what they did and in a cool way. Enter the 'hitlar' mode. bash-3.2$ ls -hitlar Shows all items with inodes, in list view, human readable size, sorted by modification time in reverse, bash-3.2$ ls -Fhitlar Shows the same with classification info. Add the hitlar mode alias to your .bashrc. bash-3.2$ echo "alias hitlar='ls -Fhitlar'" >> ~/.bashrc bash-3.2$ hitlar bash-3.2$ hitlar filename

Have netcat listening on your ports and use telnet to test connection
This will start a netcat process listening on port 666. If you are able connect to your your server, netcat will receive the data being sent and spit it out to the screen (it may look like random garbage, so you might want to redirect it to a file).

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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