Commands using grep (1,935)

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Mirror the NASA Astronomy Picture of the Day Archive
Mirror the entire NASA Astronomy Picture of the Day archive, all the way from 1995. The archive is close to 2.5 GB, with lots of files, so give it some time. The logs can be redirected to a file using '-o somefile'. You might also want to try '-nH' and the '--cut-dirs' options

Double your disk read performance in a single command
(WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: $ time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. $ blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample)

list block devices
Shows all block devices in a tree with descruptions of what they are.

continuously print string as if being entered from the keyboard
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

Preserve colors when piping tree to less

Find failures with journalctl
Sometimes things break. You can find the most recent errors using a combination of journalctl, along with the classic tools sort and uniq

ThePirateBay.org torrent search
usage: tpb searchterm example: tpb the matrix trilogy This searches for torrents from thepiratebay and displays the top results in reverse order, so the 1st result is at the bottom instead of the top -- which is better for command line users

erase content from a cdrw

Runs a command without hangups.
puts command in background and sends its output to nohup.out file it will not die if you log out fromyour shell session ;-)

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


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