Commands tagged perl (190)

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FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

list files recursively by size

Share a 'screen'-session
Ater person A starts his screen-session with `screen`, person B can attach to the srceen of person A with `screen -x`. Good to know, if you need or give support from/to others.

How to sum lines with decimals in awk
Read all lines using decimal marker as point, then add all them up and outputs the result.

Remove ( color / special / escape / ANSI ) codes, from text, with sed
Remove ( color / special / escape / ANSI ) codes, from text, with sed Credit to the original folks who I've copied this command from. The diff here is: Theirs: [m|K] Theirs is supposed to remove \E[NUMBERS;NUMBERS[m OR K] This statement is incorrect in 2 ways. 1. The letters m and K are two of more than 20+ possible letters that can end these sequences. 2. Inside []'s , OR is already assumed, so they are also looking for sequences ending with | which is not correct. This : [a-zA-Z] This resolves the "OR" issue noted above, and takes care of all sequences, as they all end with a lower or upper cased letter. This ensures 100% of any escape code 'mess' is removed.

Backup all MySQL Databases to individual files

Multi line grep using sed and specifying open/close tags
This line does not include your closing tag in the output.

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"

Access partitions inside a LVM volume
kpartx can be found inside of the multipath-tools package -a adds the mappings and -d deletes them

Install pip with Proxy
Installs pip packages defining a proxy


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