Commands by tkembo (5)

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Recursively remove directory with many files quickly
rsync'ing an empty directory over a directory to be deleted recursively is much faster than using rm -rf, for various reasons. Relevant only for directories with really a lot of files.

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"

Send your svn diff to meld
If you like to view what has been changed between revision 100 and the BASE on FILE. Meld will give you a nice overview.

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"

Set an alarm to wake up
Sleep 5h and plays the song as a wake up alarm

generate 30 x 30 matrix
or $ od /dev/urandom -w60 -An|sed 's/ ..../ /g'|head -n 30 (this one lacks digits 8 and 9)

Displays the attempted user name, ip address, and time of SSH failed logins on Debian machines
A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Create a transition between two videos
We take the first 50 frames of a.mp4 for track a, and 24 blank frames followed by b.mp4 for track b. We then create a transition from track a to track b starting from frame 25 and ending at frame 49. The output is stored in out.mp4 To view the results without saving remove "-consumer avformat:out.mp4" from the end. Documentation of the mlt framework and the melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

pipe commands from a textfile to a telnet-server with netcat
sends commands specified in $commandfile to the telnet-server specified by $telnetserver. to have newlines in $commandfile interpreted as ENTER, save the file in CR+LF (aka "Windows-Textfile") format. if you want to save the output in a separate file, use: $nc $telnetserver 23 < $commandfile > $resultfile


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