Commands by hute37 (28)

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determine if tcp port is open
for udp nmap -sU -p 80 hostname

Show the PATH, one directory per line
This is useful for examining the path.

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" }

Print a file to a LPD server
You don't need cups =)

Extract audio from Mythtv recording to Rockbox iPod using ffmpeg
There are some pretty good live performances on late night TV. With Mythtv I record David Letterman, Jimmy Fallon, and Conan nightly all in HD from over the air broadcasts. If I find a live performance I like I copy it to my Rockboxed iPod using this command. The Rockbox firmware knows how to downmix 5.1 audio. The command above extracts the audio from the video starting at 58 minutes and 15 seconds. It ends at the end of the file since this was the last performance of the recording. The command creates an ac3 file. I copy the ac3 file to my Rockbox iPod and rock on.

Use Perl like grep
Much better alternatives - grep-alikes using perl regexps. With more options, and nicer outputs.

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"

Backup all MySQL Databases to individual files
Backups all MySQL databases to individual files. Can be put into a script that grabs current date so you have per day backups.

Open (in vim) all modified files in a git repository
For editing files added to the index: $ vim `git diff --name-only --cached` To edit all changed files: $ vim `git diff --name-only HEAD` To edit changed files matching glob: $ vim `git diff --name-only -- '*.html'` If the commands needs to support filenames with whitespace, it gets a bit hacky (see http://superuser.com/questions/336016/invoking-vi-through-find-xargs-breaks-my-terminal-why for the reason): $ git diff --name-only -z | xargs -0 bash -c '

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" }


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