Net::protoent - by-name interface to Perl's built-in getproto*() 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
getprotoent(),
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
getprotobyname().
To access this functionality without the core overrides, pass the use 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 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
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