Author image Albert P Tobey




An object interface for creating SNPP servers. Almost everything you need to create your very own SNPP server is here in this module. There is a callback() method that can replace default function with your own. them. Any SNPP command can be overridden or new/custom ones can be created using custom_command(). To disable commands you just don't want to deal with, use disable_command().


There may be a synopsis here someday ...



Create a Net::SNPP::Server object listening on a port. By default, it only listens on the localhost ( - specify MultiHomed to listen on all addresses or LocalAddr to listen on only one.

 my $svr = Net::SNPP::Server->new(
    Port       => port to listen on
    BindTo     => interface address to bind to
    MultiHomed => listen on all interfaces if true (and BindTo is unset)
    Listen     => how many simultaneous connections to handle (SOMAXCONN)
    # the following two options are only used by handle_client()
    MaxErrors  => maximum number of errors before disconnecting client
    Timeout    => timeout while waiting for data (uses SIGARLM)

Calls accept() for you and returns a client handle. This method will block if there is no waiting client. The handle returned is a subclass of IO::Handle, so all IO::Handle methods should work. my $client = $server->client();


Return the IP address associated with a client handle. printf "connection from %s", $client->ip();


Returns the raw socket handle. This mainly exists for use with select() or IO::Select. my $select = IO::Select->new(); $select->add( $server->socket() );


For use with a client handle. True if server socket is still alive.


Shuts down the server socket. $server->shutdown(2);


Insert a callback into $server->callback( 'process_page', \&my_function ); $server->callback( 'validate_pager_id', \&my_function ); $server->callback( 'validate_pager_pin', \&my_function ); $server->callback( 'write_log', \&my_function ); $server->callback( 'create_id_and_pin', \&my_function );

process_page( $PAGER_ID, \%PAGE, \@RESULTS )

$PAGER_ID = [ 0 => retval of validate_pager_id 1 => retval of validate_pager_pin ] $PAGE = { mess => $, responses => [], }

validate_pager_id( PAGER_ID )

The return value of this callback will be saved as the pager id that is passed to the process_page callback as the first list element of the first argument.

validate_pager_pin( VALIDATED_PAGER_ID, PIN )

The value returned by this callback will be saved as the second list element in the first argument to process_page. The PAGER_ID input to this callback is the output from the validate_pager_id callback.

NOTE: If you really care about the PIN, you must use this callback. The default callback will return 1 if the pin is not set.


First argument is a Unix syslog level, such as "warning" or "info." The rest of the arguments are the message. Return value is ignored.


Create an ID and PIN for a 2way message.


Create a custom command or override a default command in handle_client(). The command name must be 4 letters or numbers. The second argument is a coderef that should return a text command, i.e. "250 OK" and some "defined" value to continue the client loop. +++If no value is set, the client will be disconnected after executing your command.+++ If you need MSTA or KTAG, this is the hook you need to implement them.

The subroutine will be passed the command arguments, split on whitespace.

 sub my_MSTA_sub {
    my( $id, $password ) = @_;
    # ...
    return "250 OK", 1;
 $server->custom_command( "MSTA", \&my_MSTA_sub );

Specify a command to disable in the server. This is useful, for instance, if you don't want to support level 3 commands. $server->disable_command( "2WAY", "550 2WAY not supported here" );

The second argument is an optional custom error message. The default is: "500 Command Not Implemented, Try Again"


Takes the result of $server->client() and takes care of parsing the user input. This should be quite close to being rfc1861 compliant. If you specified Timeout to be something other than 0 in new(), SIGARLM will be used to set a timeout. If you use this, make sure to take signals into account when writing your code. fork()'ing before calling handle_client is a good way to avoid interrupting code that shouldn't be interrupted.


Creates a server in a forked process. The return value is an array (or arrayref depending on context) containing a read-only pipe and the pid of the new process. Pages completed will be written to the pipe as a semicolon delimited array. my($pipe,$pid) = $server->forked_server(); my $line = $pipe->getline(); chomp( $line ); my( $pgr, $pgr, %pagedata ) = split( /;/, $line );


Al Tobey <>

Some ideas from Sendpage::SNPPServer Kees Cook <>


Add more hooks for callbacks

Implement the following level 2 and level 3 commands

 4.5.1 LOGIn <loginid> [password]
 4.5.3 LEVEl <ServiceLevel>
 4.5.5 COVErage <AlternateArea>
 4.5.7 CALLerid <CallerID>
 4.6.3 EXPTag <hours>
 4.6.5 ACKRead <0|1>
 4.6.6 RTYPe <Reply_Type_Code>


Net::Cmd Socket