.\" -*- mode: troff; coding: utf-8 -*- .\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ . ds C` "" . ds C' "" 'br\} .el\{\ . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "Net::hostent 3perl" .TH Net::hostent 3perl 2024-01-12 "perl v5.38.2" "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::hostent \- by\-name interface to Perl's built\-in gethost*() functions .SH SYNOPSIS .IX Header "SYNOPSIS" .Vb 1 \& use Net::hostent; .Ve .SH DESCRIPTION .IX Header "DESCRIPTION" This module's default exports override the core \fBgethostbyname()\fR and \&\fBgethostbyaddr()\fR functions, replacing them with versions that return "Net::hostent" objects. This object has methods that return the similarly named structure field name from the C's hostent structure from \fInetdb.h\fR; namely name, aliases, addrtype, length, and addr_list. The aliases and addr_list methods return array reference, the rest scalars. The addr method is equivalent to the zeroth element in the addr_list array reference. .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`h_\*(C'\fR. Thus, \f(CW\*(C`$host_obj\->name()\*(C'\fR corresponds to \&\f(CW$h_name\fR if you import the fields. Array references are available as regular array variables, so for example \f(CW\*(C`@{ $host_obj\->aliases() }\*(C'\fR would be simply \f(CW@h_aliases\fR. .PP The \fBgethost()\fR function is a simple front-end that forwards a numeric argument to \fBgethostbyaddr()\fR by way of Socket::inet_aton, and the rest to \fBgethostbyname()\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 2 \& use Net::hostent; \& use Socket; \& \& @ARGV = (\*(Aqnetscape.com\*(Aq) unless @ARGV; \& \& for $host ( @ARGV ) { \& \& unless ($h = gethost($host)) { \& warn "$0: no such host: $host\en"; \& next; \& } \& \& printf "\en%s is %s%s\en", \& $host, \& lc($h\->name) eq lc($host) ? "" : "*really* ", \& $h\->name; \& \& print "\etaliases are ", join(", ", @{$h\->aliases}), "\en" \& if @{$h\->aliases}; \& \& if ( @{$h\->addr_list} > 1 ) { \& my $i; \& for $addr ( @{$h\->addr_list} ) { \& printf "\etaddr #%d is [%s]\en", $i++, inet_ntoa($addr); \& } \& } else { \& printf "\etaddress is [%s]\en", inet_ntoa($h\->addr); \& } \& \& if ($h = gethostbyaddr($h\->addr)) { \& if (lc($h\->name) ne lc($host)) { \& printf "\etThat addr reverses to host %s!\en", $h\->name; \& $host = $h\->name; \& redo; \& } \& } \& } .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