1Net::protoent(3pm) Perl Programmers Reference Guide Net::protoent(3pm)
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6 Net::protoent - by-name interface to Perl's built-in getproto*()
7 functions
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10 use Net::protoent;
11 $p = getprotobyname(shift || 'tcp') || die "no proto";
12 printf "proto for %s is %d, aliases are %s\n",
13 $p->name, $p->proto, "@{$p->aliases}";
14 use Net::protoent qw(:FIELDS);
16 getprotobyname(shift || 'tcp') || die "no proto";
17 print "proto for $p_name is $p_proto, aliases are @p_aliases\n";
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20 This module's default exports override the core getprotoent(),
21 getprotobyname(), and getnetbyport() functions, replacing them with
22 versions that return "Net::protoent" objects. They take default second
23 arguments of "tcp". This object has methods that return the similarly
24 named structure field name from the C's protoent structure from
25 netdb.h; namely name, aliases, and proto. The aliases method returns
26 an array reference, the rest scalars.
27 You may also import all the structure fields directly into your
29 namespace as regular variables using the :FIELDS import tag. (Note
30 that this still overrides your core functions.) Access these fields as
31 variables named with a preceding "p_". Thus, "$proto_obj->name()"
32 corresponds to $p_name if you import the fields. Array references are
33 available as regular array variables, so for example "@{
34 $proto_obj->aliases() }" would be simply @p_aliases.
35 The getproto() function is a simple front-end that forwards a numeric
37 argument to getprotobyport(), and the rest to getprotobyname().
38 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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45 While this class is currently implemented using the Class::Struct
46 module to build a struct-like class, you shouldn't rely upon this.
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49 Tom Christiansen
50perl v5.30.1 2019-11-29 Net::protoent(3pm)