Commands by sufoo (3)

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Terminal - Prints out, what the users name, notifyed in the gecos field, is

perl one-liner to get the current week number
Not perl but shorter.

Recursively remove directory with many files quickly
rsync'ing an empty directory over a directory to be deleted recursively is much faster than using rm -rf, for various reasons. Relevant only for directories with really a lot of files.

Reverse SSH
this command from the source server and this follow in the destination server: ssh user@localhost -p 8888

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

get a random 0/1, use it for on/off, yes/no
use it to add a random boolean switch to your script

Recall “N”th command from your BASH history without executing it.

Search big files with long lines
This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error. Once you have run the above command (or put it in your .bashrc), files can be searched using: $ lgrep search-string /file/to/search

Redefine the cd command's behavior
Often, the very next command after the cd command is 'ls', so why not combine them?. Tested on a Red Hat derivative and Mac OS X Leopard Update: changed ${1:-$HOME} to "${@:-$HOME}" to accomodate directories with spaces in the names


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