Commands by ferqwerty (2)

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A bit of privacy in .bash_history
Don't track in history commands starting with whitespace. Moreover ignore duplicates from history. To be set in .bashrc ex. $ export HISTCONTROL=ignoreboth $   echo antani $   history|grep -c antani 0

Switch all connected PulseAudio bluetooth devices to A2DP profile
Tries to switch all audio devices to the A2DP profile for optimal sound quality. Useful for bluetooth speakers and headphones that always power up in HSP/HFP mode. Note however that this command is only a shorthand for the GUI, so it cannot fix stubborn BT controllers that leave your device stuck in HSP mode until a manual re-coupling.

Display all shell functions set in the current shell environment
Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'; }

gzip over ssh
I've kept the gzip compression at a low level, but depending on the cpu power available on the source machine you may want to increase it. However, SQL compresses really well, and I found even with -1 I was able to transfer 40 MiB/s over a 100 mbps wire, which was good enough for me.

Install pip with Proxy
Installs pip packages defining a proxy

Cut the first 'N' characters of a line
You can also cut charactes starting from X to N.

Have a random "cow" say a random thing
You need to have fortune and cowsay installed. It uses a subshell to list cow files in you cow directory (this folder is default for debian based systems, others might use another folder). you can add it to your .bashrc file to have it great you with something interesting every time you start a new session.

convert a mp4 video file to mp3 audio file (multiple files)

combine `mkdir foo && cd foo` into a single function `mcd foo`
I find that I create a directory and then cd into that directory quite often. I found this little function on the internets somewhere and thought I'd share it. Just copy-paste it into you ~/.bash_profile and then `source ~/.bash_profile`.

Rename files in batch


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