use strict ;
use warnings ;

my $numClients ;

use Scalar::Util qw(looks_like_number) ;

print "How many Clients are you entering?" ;  
$numClients = <STDIN> ;
chomp($numClients) ;
if ( !looks_like_number($numClients) ) {
   print "   Your input is NOT a numeric\n" ;
   exit(1) ;
}
print "$numClients\n";


__END__
C:\PerlProjects\Monks>perl getposinteger3.pl
How many Clients are you entering?0
0

C:\PerlProjects\Monks>perl getposinteger3.pl
How many Clients are you entering?  -12
  -12

C:\PerlProjects\Monks>perl getposinteger3.pl
How many Clients are you entering? 0005
 0005

C:\PerlProjects\Monks>perl getposinteger3.pl
How many Clients are you entering?14.3
14.3