Just to make sure I understand you fully.

You have the following four patterns of data:

  1. name=servername.xyz.abc.coom
  2. name=servername
  3. name=servername.xyz.com
and for each of these patterns you want to extract servername.

If the above assumptions are correct, the following will do the trick:

use Modern::Perl qw/2015/;

while (<DATA>) {
    chomp;
    say "$_ => $1" if m/name=([^\.]+)/;
}

__DATA__
name=servername.xyz.abc.coom
name=servername
name=servername.xyz.com

[download]
Output:
name=servername.xyz.abc.coom => servername
name=servername => servername
name=servername.xyz.com => servername

[download]
update:

To be fully compliant with the respective RFCs (see above), the regex should be m/name=([-0-9a-z]+)/i

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re: Steps to get a substring from a string by CountZero
in thread Steps to get a substring from a string by shroh

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