Commands by byryc69 (0)

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Short URLs with is.gd
No curl and no sed, just wget :)

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

Measures download speed on eth0

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.

Check how far along (in %) your program is in a file
Say you're started "xzcat bigdata.xz | complicated-processing-program >summary" an hour ago, and you of course forgot to enable progress output (you could've just put "awk 'NR%1000==0{print NR>"/dev/stderr"}{print}'" in the pipeline but it's too late for that now). But you really want some idea of how far along your program is. Then you can run the above command to see how many % along xzcat is in reading the file. Note that this is for the GNU/Linux version of lsof; the one found on e.g. Darwin has slightly different output so the awk part may need some tweaks.

Output entire line once per unique value of the first column
Removes duplicates in the specified field/column while outputting entire lines. An elegant command for processing tab (or otherwise) delimited data.

Search and play MP3 from Skreemr
This use the Screemr search engine to play mp3 songs

shortcut to scp a file to the same location on a remote machine
This will copy a file from your current directory to the same location on another machine. Handy for configuring ha, copying your resolv.conf, .bashrc, anything in /usr/local, etc.

lists files and folders in a folder
lists files and folders in a folder with summary.

Count the total amount of hours of your music collection
First the find command finds all files in your current directory (.). This is piped to xargs to be able to run the next shell pipeline in parallel. The xargs -P argument specifies how many processes you want to run in parallel, you can set this higher than your core count as the duration reading is mainly IO bound. The -print0 and -0 arguments of find and xargs respectively are used to easily handle files with spaces or other special characters. A subshell is executed by xargs to have a shell pipeline for each file that is found by find. This pipeline extracts the duration and converts it to a format easily parsed by awk. ffmpeg reads the file and prints a lot of information about it, grep extracts the duration line. cut and sed cut out the time information, and tr converts the last . to a : to make it easier to split by awk. awk is a specialized programming language for use in shell scripts. Here we use it to split the time elements in 4 variables and add them up.


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