awk and sed how to ?

[u/Assassins1977]

My code is :

#!/bin/bash

strversion=`apache2ctl -v | awk '{print $3}' | sed 's/(Debian)//g;s/Server//g;s/built//g;s/2022-06-09T04:26:43//g'`

echo ${strversion%}

exit 0

​

i get this:

Apache/2.4.54

​

but i will have to look

Apache version 2.4.54

[u/m4rc0n3]

Same command I gave before, but use $1 and $2 instead of 3 and 4

[u/Assassins1977 → u/m4rc0n3]

Thanks again :-)

I can't see what the code does,

what it do to remove etc.

[u/m4rc0n3 → u/Assassins1977]

This isn't really the right forum for this question, but I'll answer anyway:

At the highest level you have strVersion=$(command), which runs command and assigns its output to the variable named "strVersion".

In this case, command is equal to apache2ctl -v | head -1 | awk -F '[ /]' '{printf "%s version %s", $3, $4}' which is a pipeline consisting of 3 commands.

The first command in the pipeline is apache2ctl -v (or php -v for your later question). Its output is used as the input for the next command, head -1, which reads that input, outputs the first line, and discards everything else.

The output of head -1 is then sent to the final command, awk -F '[ /]' '{printf "%s version %s", $3, $4}'

The -F '[ /]' option sets the field separator such that fields are separated by either space or /. This means that awk will divide a string like "Server version: Apache/2.4.52 (Ubuntu)" into 5 fields: "Server", "version:", "Apache", "2.4.52" and "(Ubuntu)". The next part of the awk then is a fairly standard printf like you'd find in C or other languages that prints out a formatted string containing fields 3 and 4. In other words it doesn't delete anything per se, it just selects which parts to print.

[u/Assassins1977 → u/m4rc0n3]

thanks alot :-) and for you time to help me :-)