Commands by snorf

Commands by snorf (2)

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Calculate CPU load limit on GNU/Linux

shell order of operation example which calculates: x = number of physical CPU's y = number of cores per CPU 2(x * y) + 1 = CPU load limit Show Sample Output
This is sample output - yours may be different.
```
9
```
0

echo "$(( $(( $(grep 'physical id' '/proc/cpuinfo' | uniq | wc -l) * $(grep 'core id' '/proc/cpuinfo' | wc -l) )) * 2 + 1 ))"

snorf · 2015-11-14 20:44:39 1
create 7 variables using output of date command

minimal oneliner to keep track of time Show Sample Output
This is sample output - yours may be different.
```
echo $year $month $day $hour $minutes $seconds $epoch
2015 11 10 23 24 21 1447226661
```
0

read year month day hour minutes seconds epoch _ < <(date '+%Y %m %d %H %M %S %s')

snorf · 2015-11-11 07:27:37 0

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Alert visually until any key is pressed

I learned a few things reading this command. But I did run into a few issues: 1. On systems that don't use GNU echo (e.g. macOS 10.14.5 Mojave), the e option may not be supported. In this case ANSI escape codes will echoed as text and the terminal will not flash, like this: \e[?5h\e[38;5;1m A L E R T Thu Jun 20 16:31:29 PDT 2019 2. Since the read command strips\ignores leading backslashes, if a user types the backslash character once in the loop, it will not break. Typing backslash twice in a loop will break as expected. 3. The foreground color is set to red (\e[38;5;1m) on every loop. This could be set once before we call while, and then reset once when the loop breaks. 4. Instead of resetting the foreground color when it breaks, the video mode is set back to normal (\e[?5l). This has the effect of leaving the terminal text red until it is manually reset. The alternative I'm proposing here addresses these issues. I tested it on macOS and Arch Linux.

Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible.

Display / view the contents of the manifest within a Java jar file

Displays the manifest within a jar file. Can use it to confirm version number, etc.

Use curl with a local SOCKS5 proxy (e.g. Tor)

Routes curl input through a local SOCKS5 proxy; in this case, anonymizes curl activity via The Onion Router (Tor) proxy running locally. Note that the traffic will be anonymized, but it will NOT be encrypted, so your traffic will be very vulnerable to man-in-the-middle attacks.

list block devices

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

display a smiling smiley if the command succeeded and a sad smiley if the command failed

you could save the code between if and fi to a shell script named smiley.sh with the first argument as and then do a smiley.sh to see if the command succeeded. a bit needless but who cares ;)

tar directory and compress it with showing progress and Disk IO limits

tar directory and compress it with showing progress and Disk IO limits. Pipe Viewer can be used to view the progress of the task, Besides, he can limit the disk IO, especially useful for running Servers.

list files recursively by size

Use mtr to create a text file report

The report mode of mtr produces a text formated result of the mtr run using the number of ping cycles stated by the command. This text file could then be attached to an email with ease. I use this also without the ">" portion when writing email from within mutt using VI from the command mode with ":r !mtr --report --report-cycles 10 www.google.com" to actually input the same output in the body of an email.

Testing reading speed with dd

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