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package Net::servent; | |
use strict; | |
use 5.006_001; | |
our $VERSION = '1.02'; | |
our(@EXPORT, @EXPORT_OK, %EXPORT_TAGS); | |
our ( $s_name, @s_aliases, $s_port, $s_proto ); | |
BEGIN { | |
use Exporter (); | |
@EXPORT = qw(getservbyname getservbyport getservent getserv); | |
@EXPORT_OK = qw( $s_name @s_aliases $s_port $s_proto ); | |
%EXPORT_TAGS = ( FIELDS => [ @EXPORT_OK, @EXPORT ] ); | |
} | |
# Class::Struct forbids use of @ISA | |
sub import { goto &Exporter::import } | |
use Class::Struct qw(struct); | |
struct 'Net::servent' => [ | |
name => '$', | |
aliases => '@', | |
port => '$', | |
proto => '$', | |
]; | |
sub populate (@) { | |
return unless @_; | |
my $sob = new(); | |
$s_name = $sob->[0] = $_[0]; | |
@s_aliases = @{ $sob->[1] } = split ' ', $_[1]; | |
$s_port = $sob->[2] = $_[2]; | |
$s_proto = $sob->[3] = $_[3]; | |
return $sob; | |
} | |
sub getservent ( ) { populate(CORE::getservent()) } | |
sub getservbyname ($;$) { populate(CORE::getservbyname(shift,shift||'tcp')) } | |
sub getservbyport ($;$) { populate(CORE::getservbyport(shift,shift||'tcp')) } | |
sub getserv ($;$) { | |
no strict 'refs'; | |
return &{'getservby' . ($_[0]=~/^\d+$/ ? 'port' : 'name')}(@_); | |
} | |
1; | |
__END__ | |
=head1 NAME | |
Net::servent - by-name interface to Perl's built-in getserv*() functions | |
=head1 SYNOPSIS | |
use Net::servent; | |
$s = getservbyname(shift || 'ftp') || die "no service"; | |
printf "port for %s is %s, aliases are %s\n", | |
$s->name, $s->port, "@{$s->aliases}"; | |
use Net::servent qw(:FIELDS); | |
getservbyname(shift || 'ftp') || die "no service"; | |
print "port for $s_name is $s_port, aliases are @s_aliases\n"; | |
=head1 DESCRIPTION | |
This module's default exports override the core getservent(), | |
getservbyname(), and | |
getnetbyport() functions, replacing them with versions that return | |
"Net::servent" objects. They take default second arguments of "tcp". This object has methods that return the similarly | |
named structure field name from the C's servent structure from F<netdb.h>; | |
namely name, aliases, port, and proto. The aliases | |
method returns an array reference, the rest scalars. | |
You may also import all the structure fields directly into your namespace | |
as regular variables using the :FIELDS import tag. (Note that this still | |
overrides your core functions.) Access these fields as variables named | |
with a preceding C<s_>. Thus, C<$serv_obj-E<gt>name()> corresponds to | |
$s_name if you import the fields. Array references are available as | |
regular array variables, so for example C<@{ $serv_obj-E<gt>aliases()}> | |
would be simply @s_aliases. | |
The getserv() function is a simple front-end that forwards a numeric | |
argument to getservbyport(), and the rest to getservbyname(). | |
To access this functionality without the core overrides, | |
pass the C<use> an empty import list, and then access | |
function functions with their full qualified names. | |
On the other hand, the built-ins are still available | |
via the C<CORE::> pseudo-package. | |
=head1 EXAMPLES | |
use Net::servent qw(:FIELDS); | |
while (@ARGV) { | |
my ($service, $proto) = ((split m!/!, shift), 'tcp'); | |
my $valet = getserv($service, $proto); | |
unless ($valet) { | |
warn "$0: No service: $service/$proto\n" | |
next; | |
} | |
printf "service $service/$proto is port %d\n", $valet->port; | |
print "alias are @s_aliases\n" if @s_aliases; | |
} | |
=head1 NOTE | |
While this class is currently implemented using the Class::Struct | |
module to build a struct-like class, you shouldn't rely upon this. | |
=head1 AUTHOR | |
Tom Christiansen | |