Commands using awk (1,418)

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Check all bash scripts in current dir for syntax errors
Check all bash scripts in current dir for syntax errors WITHOUT running them.

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 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.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

edit hex mode in vim
return to normal mode from hex mode :%!xxd -r

A function to find the newest file in a directory

Recursive replace of directory and file names in the current directory.
no grep, no perl, no pipe. even better in zsh/bash4: $ for i in **/*oldname*; do "mv $i ${i/oldname/newname/}"; done No find, no grep, no perl, no pipe

Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

Screen enable/disable loggin in all windows
The command when added in screenrc enables logging all open windows by using the C-l (control-l key combination) and disable by C-o . The lines need to be added in separate lines .

Remove all old kernels
http://askubuntu.com/questions/89710/how-do-i-free-up-more-space-in-boot


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