Commands by 0x2142 (4)

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What is my ip?

intercept stdout/stderr of another process
similar to the previous command, but with more friendly output (tested on linux)

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

Quickly (soft-)reboot skipping hardware checks
If you are doing some tests which require reboots (e. g. startup skripts, kernel module parameters, ...), this is very time intensive, if you have got a hardware with a long pre-boot phase due to hardware checks. At this time, kexec can help, which only restarts the kernel with all related stuff. First the kernel to be started is loaded, then kexec -e jumps up to start it. Is as hard as a reboot -f, but several times faster (e. g. 1 Minute instead of 12 on some servers here).

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

list files recursively by size

Rename files in batch

list files recursively by size

combine `mkdir foo && cd foo` into a single function `mcd foo`
I find that I create a directory and then cd into that directory quite often. I found this little function on the internets somewhere and thought I'd share it. Just copy-paste it into you ~/.bash_profile and then `source ~/.bash_profile`.

move you up one directory quickly
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.


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