1Net::servent(3pm)      Perl Programmers Reference Guide      Net::servent(3pm)
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NAME

6       Net::servent - by-name interface to Perl's built-in getserv*()
7       functions
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SYNOPSIS

10        use Net::servent;
11        $s = getservbyname(shift || 'ftp') || die "no service";
12        printf "port for %s is %s, aliases are %s\n",
13           $s->name, $s->port, "@{$s->aliases}";
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15        use Net::servent qw(:FIELDS);
16        getservbyname(shift || 'ftp') || die "no service";
17        print "port for $s_name is $s_port, aliases are @s_aliases\n";
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DESCRIPTION

20       This module's default exports override the core getservent(),
21       getservbyname(), and getnetbyport() functions, replacing them with
22       versions that return "Net::servent" objects.  They take default second
23       arguments of "tcp".  This object has methods that return the similarly
24       named structure field name from the C's servent structure from netdb.h;
25       namely name, aliases, port, and proto.  The aliases method returns an
26       array reference, the rest scalars.
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28       You may also import all the structure fields directly into your
29       namespace as regular variables using the :FIELDS import tag.  (Note
30       that this still overrides your core functions.)  Access these fields as
31       variables named with a preceding "s_".  Thus, "$serv_obj->name()"
32       corresponds to $s_name if you import the fields.  Array references are
33       available as regular array variables, so for example "@{
34       $serv_obj->aliases()}" would be simply @s_aliases.
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36       The getserv() function is a simple front-end that forwards a numeric
37       argument to getservbyport(), and the rest to getservbyname().
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39       To access this functionality without the core overrides, pass the "use"
40       an empty import list, and then access function functions with their
41       full qualified names.  On the other hand, the built-ins are still
42       available via the "CORE::" pseudo-package.
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EXAMPLES

45        use Net::servent qw(:FIELDS);
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47        while (@ARGV) {
48            my ($service, $proto) = ((split m!/!, shift), 'tcp');
49            my $valet = getserv($service, $proto);
50            unless ($valet) {
51                warn "$0: No service: $service/$proto\n"
52                next;
53            }
54            printf "service $service/$proto is port %d\n", $valet->port;
55            print "alias are @s_aliases\n" if @s_aliases;
56        }
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NOTE

59       While this class is currently implemented using the Class::Struct
60       module to build a struct-like class, you shouldn't rely upon this.
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AUTHOR

63       Tom Christiansen
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67perl v5.28.2                      2018-11-01                 Net::servent(3pm)
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