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 00:37:07 237
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 03:11:51 526
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 00:49:25 217

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list block devices

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

FInd the 10 biggest files taking up disk space

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Countdown Clock

Countdown clock - Counts down from $MIN minutes to zero. I let the date command do the maths. This version doesn't use seq.

split and combine different pages from different pdf's

The command shows the real power of the pdftk tool, you can do basically everything you want with multiple pdf's. In the command a book is created from chapters, headings and covers.

List the most recent dates in reverse-chronological order

check open ports without netstat or lsof

Show a 4-way scrollable process tree with full details.

If you want a visual representation of the parent/child relationships between processes, this is one easy way to do it. It's useful in debugging collections of shell scripts, because it provides something like a call traceback. When a shell script breaks, just remember "awwfux".

Immediately put execute permission on any file saved/created in $HOME/bin

Smart `cd`.. cd to the file directory if you try to cd to a file

This little function will smarten 'cd'. If you try to cd into a file (which I guess we all have done), it cd's into the directory of that file instead. I had to use nesten if's, to get cd to still work with 'cd' (to get to $HOME), 'cd -' (to get to last directory), and 'cd foo\ bar'.

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