1package Net::servent 1.04; 2use v5.38; 3 4our ( $s_name, @s_aliases, $s_port, $s_proto ); 5 6use Exporter 'import'; 7our @EXPORT = qw(getservbyname getservbyport getservent getserv); 8our @EXPORT_OK = qw( $s_name @s_aliases $s_port $s_proto ); 9our %EXPORT_TAGS = ( FIELDS => [ @EXPORT_OK, @EXPORT ] ); 10 11use Class::Struct qw(struct); 12struct 'Net::servent' => [ 13 name => '$', 14 aliases => '@', 15 port => '$', 16 proto => '$', 17]; 18 19sub populate { 20 return unless @_; 21 my $sob = new(); 22 $s_name = $sob->[0] = $_[0]; 23 @s_aliases = @{ $sob->[1] } = split ' ', $_[1]; 24 $s_port = $sob->[2] = $_[2]; 25 $s_proto = $sob->[3] = $_[3]; 26 return $sob; 27} 28 29sub getservent :prototype( ) { populate(CORE::getservent()) } 30sub getservbyname :prototype($;$) { populate(CORE::getservbyname(shift,shift||'tcp')) } 31sub getservbyport :prototype($;$) { populate(CORE::getservbyport(shift,shift||'tcp')) } 32 33sub getserv :prototype($;$) { 34 no strict 'refs'; 35 return &{'getservby' . ($_[0]=~/^\d+$/ ? 'port' : 'name')}(@_); 36} 37 38__END__ 39 40=head1 NAME 41 42Net::servent - by-name interface to Perl's built-in getserv*() functions 43 44=head1 SYNOPSIS 45 46 use Net::servent; 47 my $s = getservbyname(shift || 'ftp') || die "no service"; 48 printf "port for %s is %s, aliases are %s\n", 49 $s->name, $s->port, "@{$s->aliases}"; 50 51 use Net::servent qw(:FIELDS); 52 getservbyname(shift || 'ftp') || die "no service"; 53 print "port for $s_name is $s_port, aliases are @s_aliases\n"; 54 55=head1 DESCRIPTION 56 57This module's default exports override the core getservent(), 58getservbyname(), and 59getnetbyport() functions, replacing them with versions that return 60"Net::servent" objects. They take default second arguments of "tcp". This object has methods that return the similarly 61named structure field name from the C's servent structure from F<netdb.h>; 62namely name, aliases, port, and proto. The aliases 63method returns an array reference, the rest scalars. 64 65You may also import all the structure fields directly into your namespace 66as regular variables using the :FIELDS import tag. (Note that this still 67overrides your core functions.) Access these fields as variables named 68with a preceding C<s_>. Thus, C<$serv_obj-E<gt>name()> corresponds to 69$s_name if you import the fields. Array references are available as 70regular array variables, so for example C<@{ $serv_obj-E<gt>aliases()}> 71would be simply @s_aliases. 72 73The getserv() function is a simple front-end that forwards a numeric 74argument to getservbyport(), and the rest to getservbyname(). 75 76To access this functionality without the core overrides, 77pass the C<use> an empty import list, and then access 78function functions with their full qualified names. 79On the other hand, the built-ins are still available 80via the C<CORE::> pseudo-package. 81 82=head1 EXAMPLES 83 84 use Net::servent qw(:FIELDS); 85 86 while (@ARGV) { 87 my ($service, $proto) = ((split m!/!, shift), 'tcp'); 88 my $valet = getserv($service, $proto); 89 unless ($valet) { 90 warn "$0: No service: $service/$proto\n" 91 next; 92 } 93 printf "service $service/$proto is port %d\n", $valet->port; 94 print "alias are @s_aliases\n" if @s_aliases; 95 } 96 97=head1 NOTE 98 99While this class is currently implemented using the Class::Struct 100module to build a struct-like class, you shouldn't rely upon this. 101 102=head1 AUTHOR 103 104Tom Christiansen 105