How to print specific lines of a text file with cut

Question

I have the next fragment of the output of a log:

Server Server: Server
Date and Time: June 04 2018 14:10:00
--

Product     Version         User         Host             IP             Duration

Software1      11.0     user               user         *.**.***.***     10:08
Software2      11.0      user                user        *.**.***.***     10:05
===================================================================================

I want with cut command only filter to the output like:

Product     Version         Host             IP             Duration

Software1      11.0    user             *.**.***.***     10:08
Software2      11.0     user            *.**.***.***     10:05

Also, I want to know if is possible apply the same filter many times, because the first example above, it repeats himself in the whole file.

Answer 1

You can't really use cut in this case as the columns of the data are not clearly defined. The cut utility works by cutting at exact numbers, e.g. exactly at 3 spaces or tabs or whatever delimiter you have. In this case, you will need to use awk which splits its input lines on any number of consecutive whitespaces (by default).

$ awk -v OFS="\t" '/^==/ { next } NR > 4 { print $1, $2, $4, $5, $6 }' file | column -t
Product    Version  Host  IP            Duration
Software1  11.0     user  *.**.***.***  10:08
Software2  11.0     user  *.**.***.***  10:05

The awk program skips any line starting with == and any line before the 5th line. For all other lines, it prints a selection of the fields (not the 3rd, User).

The column -t at the end formats the result into a nice table.

Answer 2

Using awk:

 awk '/--/{flag=1; next} /====/{flag=0} flag' filename

Using SED:

 sed -n '/--/,/===/{/--/!{/===/!p}}' filename

Using grep:

grep -E 'Product|Mathematica|MathKernel|Syntax' filename

Answer 3

I found the simplest solution to this:

awk '{print $1,$2,$4,$5,$6}' file1.log > file2.log

This allows only print my preferred columns

Product     Version         Host             IP             Duration

Software1       11.0         User          *.**.***.***     10:08
Software2        11.0        User           *.**.***.***     10:05

I didn't realize the important use of awk