Hello rajkk04, and welcome to the Monastery!

i want to extract only 4 letters (alphanumeric) in the complete text.

Assuming this means: Match the first alphanumeric word of exactly 4 characters appearing between double quotes:

#! perl
use strict;
use warnings;

my $s = '"perl"monks';
$s =~ m{ " (\w{4}) " }x;
print $1, "\n" if $1;

[download]

Output:

23:31 >perl 475_SoPW.pl
perl

23:31 >

[download]

See “Quantifiers” under perlre#Regular-Expressions.

Update: If you need to match strictly alphanumeric characters only (no punctuation characters), change \w in the regex to [A-Za-z0-9].

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Extracting Strings - Special Cases by Athanasius
in thread Extracting Strings - Special Cases by rajkk04

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