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You're most welcome!

Here's the regex in the grep (with two added features that should be there):

/^\Q$host\E$/; ^ ^ ^^ | | || | | |+ - End of line | | + - End quote metacharacters | + - Begin quote metacharacters (e.g., [.*\+], etc.) + - Match beginning at the start of the line

If you remove the trailing $, it'll match a host name beginning with "db". Try the following with and without the trailing $ in the regex:

use warnings; use strict; my $host = 'db'; while (<DATA>) { print if /^\Q$host\E$/i; } __DATA__ db db4323 dbwindows822.tp.com db726.tp.com

Output with $:

db

This is because if forces an exact match, like $host eq 'db'.

Output without $:

db db4323 dbwindows822.tp.com db726.tp.com

This is becuase it's only matching the first two characters of $_ (the default scalar) against the value of $host.

Note that there's the i modifier at the end of the regex. This makes the match case-insensitive, in case you have a host like DB4323.


In reply to Re^5: If conditional checks by Kenosis
in thread If conditional checks by kitkit201

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