Commands using echo (1,545)

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Calculates the number of physical cores considering HyperThreading in AWK
Check whether hyperthreading is enabled or not. a better solution as nproc should work on all OS with awk

Search for a string inside all files in the current directory
shorter typing with no need to use xargs.

remove hostname from known_hosts

Display or use a random file from current directory via a small bash one-liner
An other way to run it ( playing a random file ending with avi, flv or mpeg ) from a specified dir and a specified type of extension : making MOVIE array with a glob : $ MOVIE=( /PATH/TO/MY/FAVORITE/MOVIES/*.{avi,flv,mpeg} ) playing the random file from a random key from the array $ mplayer ${MOVIE[ RANDOM % ( ${#i[@]} + 1 ) ]]} I use only globs and a bash array. I use GNU bash, version 3.2.48

Install pip with Proxy
Installs pip packages defining a proxy

Content search.
Grep will read the contents of each file in PWD and will use the REs $1 $2 ... $n to match the contents. In case of match, grep will print the appropriate file, line number and the matching line. It's just easier to write $ ff word1 word2 word3 Instead of $ grep -rinE 'word1|word2|word3' .

Clone all repos from a user with lynx
https://wuseman.github.io/wcloner/

Start dd and show progress every X seconds

Generate RSA private key and self-signed certificate
This will create, in the current directory, a file called 'pk.pem' containing an unencrypted 2048-bit RSA private key and a file called 'cert.pem' containing a certificate signed by 'pk.pem'. The private key file will have mode 600. !!ATTENTION!! ==> this command will overwrite both files if present.

Record a webcam output into a video file.
The option -an disables audio recording, -f forces the use of video4linux for the input, -s sets the video to the size 320x240, -b sets the recording bitrate, -r sets the frame rate to 15fps, -i gives the input device, -vcodec sets the output format. Press Q to stop recording or you can specify the recording time with the -t option like -t 00:1:30


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