Net::protoent(3p)Perl Programmers Reference GuidNet::protoent(3p)
Net::protoent - by-name interface to Perl's built-in get-
proto*() functions
use Net::protoent;
$p = getprotobyname(shift || 'tcp') || die "no proto";
printf "proto for %s is %d, aliases are %s\n",
$p->name, $p->proto, "@{$p->aliases}";
use Net::protoent qw(:FIELDS);
getprotobyname(shift || 'tcp') || die "no proto";
print "proto for $p_name is $p_proto, aliases are @p_aliases\n";
This module's default exports override the core getpro-
toent(), getprotobyname(), and getnetbyport() functions,
replacing them with versions that return "Net::protoent"
objects. They take default second arguments of "tcp". This
object has methods that return the similarly named structure
field name from the C's protoent structure from netdb.h;
namely name, aliases, and proto. The aliases method returns
an array reference, the rest scalars.
You may also import all the structure fields directly into
your namespace as regular variables using the :FIELDS import
tag. (Note that this still overrides your core functions.)
Access these fields as variables named with a preceding
"p_". Thus, "$proto_obj->name()" corresponds to $p_name if
you import the fields. Array references are available as
regular array variables, so for example "@{
$proto_obj->aliases() }" would be simply @p_aliases.
The getproto() function is a simple front-end that forwards
a numeric argument to getprotobyport(), and the rest to get-
protobyname().
To access this functionality without the core overrides,
pass the "use" an empty import list, and then access func-
tion functions with their full qualified names. On the other
hand, the built-ins are still available via the "CORE::"
pseudo-package.
While this class is currently implemented using the
Class::Struct module to build a struct-like class, you
shouldn't rely upon this.
Tom Christiansen
perl v5.8.8 2005-02-05 1