Dear Monks, Could you please improve this code, i am new to perl, trying to see if i can do this code in a better way 
my $sshport;
my $errorstate = 0;

print "\n Please Enter Custom port for SSH server:\n";
chomp($sshport = <STDIN>);
while (!$errorstate) {
    if ($sshport =~  /^[1-9]\d{1,9}$/ ) {
        $errorstate = 1;
    } else {
        print " Please Enter valid ssh port number:\n";
        chomp($sshport = <STDIN>);
    }
}

open (SSHD_CONFIG,'sshd_config') or die ("Could not able to open the f
+ile $!");
open (SSHD_CONFIG_NEW,">",'sshd_config.new') or die ("Could not create
+ the new file $!");

while (<SSHD_CONFIG>){
 if (/^port/i) {
    s/Port.+/Port $sshport/;
 } elsif (/^#port\s/i) {
    s/#Port.+/Port $sshport/;
 }
 print SSHD_CONFIG_NEW $_;
}

rename('sshd_config','sshd_config.old');
rename('sshd_config.new','sshd_config');

[download]

In reply to Defactor this code by xerophyte

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.