Commands by livibetter (4)

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Get full from half remembered commands
Show all commands having the part known by you. Eg: $apropos pdf | less

Find the package that installed a command

a shell function to print a ruler the width of the terminal window.
A similar version for Bash that doesn't require cut and shortens the function in a few places. And it uses local variables. (similar to a version by eightmillion in a comment on the another version)

Print a row of 50 hyphens
essentially the ruby one, but perhaps has a larger installed base

Execute a command with a timeout
In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

check open ports without netstat or lsof

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" }

Exclude svn directories with grep
exclude-dir option requires grep 2.5.3

mix video and audio
-map 0.0:0 map the video of video.mp4 to the video of mix.mp4 -map 1.0:1 map the audio of audio.mp3 to the audio of mix.mp4 make sure that video.mp4 and audio.mp3 have the same duration

Another Matrix Style Implementation


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