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Create iso image of cd/dvd

Get the total length of all videos in the current dir in H:m:s
You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds. Someone better at awk could probably reduce this down a lot.

Record your desktop
That will capture 200 seconds of video at fullscreen 1680x1050 resolution, but scaled down 25 percent, with 15 frames per second. http://fusioncast.blogspot.com/2007/09/infobyte-how-i-record-my-desktop.html

Add temporary <1m entries to old cron
Old cron doesn't allow periods

A command to copy mysql tables from a remote host to current host via ssh.
In the example above 3 tables are copied. You can change the number of tables. You should be able to come up with variants of the command by modifying the mysqldump part easily, to copy some part of remote mysql DB.

Save current layout of top
'top' has fancy layout modes where you can have several windows with different things displayed. You can configure a layout and then save it with 'W'. It will then be restored every time you run top. E.g. to have two colored windows, one sorted by CPU usage, the other by memory usage, run top $ top then press the keys $ and then as you don?t want to repeat this the next time: $

Limit the cpu usage of a process
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: $ bc -l

computes the most frequent used words of a text file
using $ cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30 ("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...

Automatically find and re-attach to a detached screen session
man screen: "-D -R Attach here and now. In detail this means: If a session is running, then reattach. If necessary detach and logout remotely first. If it was not running create it and notify the user. This is the author?s favorite."

Find broken symlinks and delete them


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