Commands by mikhail (9)

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check web server port 80 response header

Define words and phrases with google.
This function takes a word or a phrase as arguments and then fetches definitions using Google's "define" syntax. The "nl" and perl portion isn't strictly necessary. It just makes the output a bit more readable, but this also works: $define(){ local y="[email protected]";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?/dev/null;}

List all commands present on system
List all commands present on system by folder. $PATH contains all command folder separated by ':'. With ${PATH//:/ }, we change ':' in space and create a list of folder for ls command.

send DD a signal to print its progress
every 1sec sends DD the USR1 signal which causes DD to print its progress.

Monitor memory fine-grained usage (e.g. firefox)
Sometimes top/htop don't give the fine-grained detail on memory usage you might need. Sum up the exact memory types you want

Stream audio over ssh
This will allow you to convert an audio file to wav format, and send it via ssh to a player on the other computer, which will open and play it there. Of course, substitute your information for the sound file and remote address You do not have to use paplay on the remote end, as it is a PulseAudio thing. If the remote end uses ALSA, you should use aplay instead. If it uses OSS, you should berate them about having a lousy sound system. Also, you're not limited to transmitting encoded as wav either, it's just that AFAIK, most systems don't come with mp3 codecs, but will play wav files fine. If you know SoX is installed on the remote end and has mp3 codecs, you can use the following instead: $ cat Klaxon.mp3 |ssh [email protected] play -t mp3 - this will transmit as mp3. Again, use your specific information. if you're not playing mp3s, use another type with the -t option

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" }

list block devices
Shows all block devices in a tree with descruptions of what they are.

mercurial close branch

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.


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