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.\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.43)
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.\" ========================================================================
.\"
.IX Title "Net::servent 3perl"
.TH Net::servent 3perl "2023-11-25" "perl v5.36.0" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
Net::servent \- by\-name interface to Perl's built\-in getserv*() functions
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 4
\& use Net::servent;
\& $s = getservbyname(shift || \*(Aqftp\*(Aq) || die "no service";
\& printf "port for %s is %s, aliases are %s\en",
\&    $s\->name, $s\->port, "@{$s\->aliases}";
\&
\& use Net::servent qw(:FIELDS);
\& getservbyname(shift || \*(Aqftp\*(Aq) || die "no service";
\& print "port for $s_name is $s_port, aliases are @s_aliases\en";
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
This module's default exports override the core \fBgetservent()\fR,
\&\fBgetservbyname()\fR, and
\&\fBgetnetbyport()\fR functions, replacing them with versions that return
\&\*(L"Net::servent\*(R" objects.  They take default second arguments of \*(L"tcp\*(R".  This object has methods that return the similarly
named structure field name from the C's servent structure from \fInetdb.h\fR;
namely name, aliases, port, and proto.  The aliases
method returns an array reference, the rest scalars.
.PP
You may also import all the structure fields directly into your namespace
as regular variables using the :FIELDS import tag.  (Note that this still
overrides your core functions.)  Access these fields as variables named
with a preceding \f(CW\*(C`s_\*(C'\fR.  Thus, \f(CW\*(C`$serv_obj\->name()\*(C'\fR corresponds to
\&\f(CW$s_name\fR if you import the fields.  Array references are available as
regular array variables, so for example \f(CW\*(C`@{ $serv_obj\->aliases()}\*(C'\fR
would be simply \f(CW@s_aliases\fR.
.PP
The \fBgetserv()\fR function is a simple front-end that forwards a numeric
argument to \fBgetservbyport()\fR, and the rest to \fBgetservbyname()\fR.
.PP
To access this functionality without the core overrides,
pass the \f(CW\*(C`use\*(C'\fR an empty import list, and then access
function functions with their full qualified names.
On the other hand, the built-ins are still available
via the \f(CW\*(C`CORE::\*(C'\fR pseudo-package.
.SH "EXAMPLES"
.IX Header "EXAMPLES"
.Vb 1
\& use Net::servent qw(:FIELDS);
\&
\& while (@ARGV) {
\&     my ($service, $proto) = ((split m!/!, shift), \*(Aqtcp\*(Aq);
\&     my $valet = getserv($service, $proto);
\&     unless ($valet) {
\&         warn "$0: No service: $service/$proto\en"
\&         next;
\&     }
\&     printf "service $service/$proto is port %d\en", $valet\->port;
\&     print "alias are @s_aliases\en" if @s_aliases;
\& }
.Ve
.SH "NOTE"
.IX Header "NOTE"
While this class is currently implemented using the Class::Struct
module to build a struct-like class, you shouldn't rely upon this.
.SH "AUTHOR"
.IX Header "AUTHOR"
Tom Christiansen