juster's advice to do the job in Perl is sound and the task need not take many lines of code.

use strict;
use warnings;

my @wantedLines =
   grep { m{^fileid} .. m{^-----} and m{pattern} } <>;

print for @wantedLines;

[download]

Here is a pretend log file.

$ cat spw765108.log 
a line
another line
fileid 123
some data
a pattern we want
some more data
another wanted pattern
yet more data
-----
another line
a pattern outside our bounds
last line
$

[download]

Now run the script, giving the log file as an argument.

$ ./spw765108 spw765108.log 
a pattern we want
another wanted pattern
$

[download]

The <> reads the filehandle automatically opened on the file (or files) supplied as arguments to the script. The built-in grep filters the lines read from the filehandle to pass into @wantedLines only those that satisfy the conditions set. The first condition uses the range operator (also known as the flip-flop operator) to select only those lines between the two conditions. A further test to see if any lines match the desired pattern also has to be true.

I hope this is helpful.

Cheers,

JohnGG

In reply to Re: usage of awk and grep together by johngg
in thread usage of awk and grep together by raghu_shekar

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