Commands using bc (51)

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print lib path of perl

Generate a random left-hand password
Generates a random 8-character password that can be typed using only the left hand on a QWERTY keyboard. Useful to avoid taking your hand off of the mouse, especially if your username is left-handed. Change the 8 to your length of choice, add or remove characters from the list based on your preferences or kezboard layout, etc.

Count opening and closing braces in a string.
This function counts the opening and closing braces in a string. This is useful if you have eg long boolean expressions with many braces and you simply want to check if you didn't forget to close one.

restoring some data from a corrupted text file
man tac When there is a bad block in the middle of your file, you can see its begninning with `cat' and its end with `tac'. But both commands terminates with an error. So this sequence rebuilds a new file without badblock.

Blink LED Port of NIC Card
Blinks LED of a NIC card. Its used when you have multiple NICs and you want to identify the physical port of a particular ethernet card.

Fibonacci numbers with awk
Another combination of seq and awk. Not very efficient, but sufficiently quick.

Create date based backups
This script creates date based backups of the files. It copies the files to the same place the original ones are but with an additional extension that is the timestamp of the copy on the following format: YearMonthDay-HourMinuteSecond

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"

bash find function
basic find implementation for systems that don't actually have find, like an android console without busybox installed.

MSDOS command to check existance of command and exit batch if failed
This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits. An error message of the command itself is suppressed for clarity purpose.


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