Commands by Negate

Commands by Negate (3)

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Check a directory of PNG files for errors

Useful for checking if a large number of PNG files was downloaded successfully by verifying the built-in CRC checksum. For incomplete files, the command will print: "00002309.png EOF while reading IDAT data ERROR: 00002309.png" The process is very fast; checking 21,000 files of 5MB in size took only five minutes on a 2011 Intel mobile dual-core.
This is sample output - yours may be different.
1

ls *.png |parallel --nice 19 --bar --will-cite "pngcheck -q {}"

Negate · 2021-09-05 00:37:07 380
Print process run time, average CPU usage, and maximum memory usage on exit

Bash has a built-in time command which provides less functionality than the real time command. Thus we reference /usr/bin/time directly. Since the command isn't very easy to remember you could alias it to something like "cputime" or even just "time". Show Sample Output
This is sample output - yours may be different.
```
/usr/bin/time -f "\ntime\t%E\nCPU\t%P\nRAM\t%Mk" sleep 10

time	0:10.00
CPU	0%
RAM	2216k
```
1

/usr/bin/time -f "\ntime\t%E\nCPU\t%P\nRAM\t%Mk" <command>

Negate · 2018-10-27 03:11:51 643
Create a simple video contact sheet using the vcs bash script

Assumes you've downloaded Toni Corvera's vcs script (http://p.outlyer.net/vcs), have it in your PATH, and have installed the script's dependencies. Generates a video contact sheet of 24 thumbnails and 3 thumbnails per column. The bold font and white-on-black color scheme keeps the text readable at the chosen 70% JPEG compression quality, which keeps the file size at a manageable level. You can go even lower with the quality and get a good looking result.
This is sample output - yours may be different.
2

vcs -c 3 -H 220 -n 24 -dt -ds -dp -j --anonymous -O bg_heading=black -O bg_sign=black -O fg_heading=white -O fg_heading=white -O fg_sign=white -O fg_title=white -O font_heading=DejaVu-Sans-Bold -O quality=70

Negate · 2018-06-06 00:49:25 298

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The wisdom of Cave Johnson

There's been a similar Futurama thing around for a while, which grabs a quote from the /. headers [curl -Ism3 slashdot.org | egrep "^X-(F|B|L)" | cut -d \- -f 2- | fmt -w $(tput cols)]. Same deal, but more likely to stop working when someone forgets to pay the bill on the domain. Until then: Cave Johnson!

Should I be sleeping?

Change prompt to MS-DOS one (joke)

This one eliminates the additional backslash at the end (which is not necessary)

Press Any Key to Continue

Find out current working directory of a process

Installing debian on fedora (chrooted)

return external ip

remove comments (even those starting with spaces), empty lines (even those containing spaces) in one grep command

useful for discarding even those comments which start with blanks or those empty lines which contain blanks

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"

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

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