Commands by sinevar (1)

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Screenshot Directly To Clipboard
This will take a screenshot of a selected area and save it as foo.png as well as sending it straight to the clipboard for pasting into GIMP, Anki, Zim, etc.

Test disk I/O
Especially useful to gauge the performance of a VPS.

Connect to remote machine with other enconding charset

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

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

List .log files open by a pid
Uses lsof to display the full path of ".log" files opened by a specified PID.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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)

Send youtube video to Kodi
Kodi needs the youtube plugin to be installed.

Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

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