Commands by wekoch (2)

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Count items in JSON array
Pipe any JSON to jq, then count with the appropiate expression and use the | length on the array

Backup entire system through SSH

Show linux kernel modules dependencies
Use modprobe to list all the dependencies of a certain kernel module. Handy when debugging system issues.

check open ports without netstat or lsof

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

Duplicate several drives concurrently
If you have some drive imaging to do, you can boot into any liveCD and use a commodity machine. The drives will be written in parallel. To improve efficiency, specify a larger block size in dd: $dd if=/dev/sda bs=64k | tee >(dd of=/dev/sdb bs=64k) | dd of=/dev/sdc bs=64k To image more drives , insert them as additional arguments to tee: $dd if=/dev/sda | tee >(dd of=/dev/sdb) >(dd of=/dev/sdc) >(dd of=/dev/sdd) | dd of=/dev/sde

Send a file to a pastebin from STDIN or a file, with a single function
echo "Hello world!" | sprunge # Redirect a stream to a pastebin sprunge ~/.bashrc # Send a file to a pastebin

Download file with multiple simultaneous connections
jrk's aria2 example is incorrect. -s specifies the global connection limit; the per-host connection limit is specified with -x.

open a screenshot of a remote desktop via ssh
standard image viewers do not seem to be able to open a FIFO file. xloadimage was the first one i've stumbled upon that can handle this.

delete all leading and trailing whitespace from each line in file


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