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Net::TCP - TCP sockets interface module
use Net::Gen; # optional
use Net::Inet; # optional
use Net::TCP;
The Net::TCP module provides services for TCP communications
over sockets. It is layered atop the
Net::Inet
and
Net::Gen
modules, which are part of the same distribution.
The following methods are provided by the Net::TCP module
itself, rather than just being inherited from
Net::Inet
or
Net::Gen.
Usage:
$obj = new Net::TCP;
$obj = new Net::TCP $host, $service;
$obj = new Net::TCP \%parameters;
$obj = new Net::TCP $host, $service, \%parameters;
$obj = 'Net::TCP'->new();
$obj = 'Net::TCP'->new($host, $service);
$obj = 'Net::TCP'->new(\%parameters);
$obj = 'Net::TCP'->new($host, $service, \%parameters);
Returns a newly-initialised object of the given class. If called
for a derived class, no validation of the supplied parameters
will be performed. (This is so that the derived class can add
the parameter validation it needs to the object before allowing
the validation.) Otherwise, it will cause the parameters to be
validated by calling its init method, which Net::TCP
inherits from Net::Inet. In particular, this means that if
both a host and a service are given, then an object will only be
returned if a connect() call was successful (or is still in progress,
if the object is non-blocking).
The examples above show the indirect object syntax which many prefer, as well as the guaranteed-to-be-safe static method call. There are occasional problems with the indirect object syntax, which tend to be rather obscure when encountered. See http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-01/msg01674.html for details.
none.
These are the socket options known to the Net::TCP module itself:
TCP_NODELAY TCP_MAXSEG TCP_RPTR2RXT
There are no object parameters registered by the Net::TCP module itself.
Tieing of scalars to a TCP handle is supported by inheritance
from the TIESCALAR method of
Net::Gen. That method only
succeeds if a call to a new method results in an object for
which the isconnected method returns true, which is why it is
mentioned in connection with this module.
Example:
tie $x,Net::TCP,0,'finger' or die;
$x = "-s\015\012";
print $y while defined($y = $x);
untie $x;
This is an expensive re-implementation of finger -s on many machines.
Each assignment to the tied scalar is really a call to the put
method (via the STORE method), and each read from the tied
scalar is really a call to the getline method (via the
FETCH method).
none
TCPOPT_EOL TCPOPT_MAXSEG TCPOPT_NOP TCPOPT_WINDOW
TCP_MAXSEG TCP_MAXWIN TCP_MAX_WINSHIFT TCP_MSS
TCP_NODELAY TCP_RPTR2RXT TH_ACK TH_FIN TH_PUSH TH_RST
TH_SYN TH_URG
The following :tags are available for grouping related exportable items:
TCP_NODELAY TCP_MAXSEG TCP_RPTR2RXT
TCPOPT_EOL TCPOPT_MAXSEG TCPOPT_NOP TCPOPT_WINDOW
TCP_MAXWIN TCP_MAX_WINSHIFT TCP_MSS TH_ACK TH_FIN
TH_PUSH TH_RST TH_SYN TH_URG
All of the above exportable items.
This module has been tested with threaded perls, and should be as thread-safe as perl itself. (As of 5.005_03 and 5.005_57, that's not all that safe just yet.) It also works with interpreter-based threads ('ithreads') in more recent perl releases.
Net::Inet(3), Net::Gen(3), Net::TCP::Server(3)
Spider Boardman <spidb@cpan.org>