Ubuntu Manpage: dnet_daemon, dnet_accept, dnet_reject

NAME

       dnet_daemon, dnet_accept, dnet_reject - DECnet daemon functions

SYNOPSIS

       #include <netdnet/dn.h>
       #include <netdnet/dnetdb.h>
       -ldnet -ldnet_daemon -lcrypt

       int dnet_daemon (int object, char *named_object, int verbosity, int do_fork)
       void dnet_accept (int sockfd, short status, char *data, int len)
       void dnet_reject (int sockfd, short status, char *data, int len)

DESCRIPTION

       These  functions  are the core of writing a DECnet daemon under Linux. They provide all the functionality
       necessary to have a daemon that will run standalone or be forked from the dnetd(8)  DECnet  super-server.
       (see dnetd.conf(3) for information on configuring dnetd.
       dnet_daemon()  returns  a  connected file descriptor which your daemon program uses to talk to the remote
       client. If your daemon is run from dnetd then this will be it's standard input.
       object is the numbered object which your daemon binds to. Alternatively you can bind to a
       named_object in which case the object number should be zero.
       verbosity determines how much logging the daemon functions will do. 0  means  no  logging,  1  is  fairly
       verbose logging. Anything higher is useful only for debugging.
       do_fork  If  this  is  set then, when running standalone, the daemon will fork and detach itself from the
       parent process.

       dnet_accept() You MUST call  this  or  dnetd_reject()  after  receiving  a  valid  file  descriptor  from
       dnet_daemon.  The  optional  data and status parameters provide extra information to the connecting host.
       See below for status values.

       dnet_reject() If you wish to reject the connection for any reason  the  call  this  function  instead  of
       dnet_accept()  with  the  status  set to the reason (see below) you are rejecting the connection. If your
       daemon is authenticated by dnetd then connections will already be rejected  if  they  are  not  correctly
       authorized by either a valid username/password or the proxy database (see decnet.proxy(3) )
       Here is a list of status codes available in dnetd.conf:

       #define DNSTAT_REJECTED         0 /* Rejected by object */
       #define DNSTAT_RESOURCES        1 /* No resources available */
       #define DNSTAT_NODENAME         2 /* Unrecognised node name */
       #define DNSTAT_LOCNODESHUT      3 /* Local Node is shut down */
       #define DNSTAT_OBJECT           4 /* Unrecognised object */
       #define DNSTAT_OBJNAMEFORMAT    5 /* Invalid object name format */
       #define DNSTAT_TOOBUSY          6 /* Object too busy */
       #define DNSTAT_NODENAMEFORMAT  10 /* Invalid node name format */
       #define DNSTAT_REMNODESHUT     11 /* Remote Node is shut down */
       #define DNSTAT_ACCCONTROL      34 /* Access control rejection */
       #define DNSTAT_NORESPONSE      38 /* No response from object */
       #define DNSTAT_NODEUNREACH     39 /* Node Unreachable */

       /* Disconnect notification errors */
       #define DNSTAT_MANAGEMENT       8 /* Abort by management/third party */
       #define DNSTAT_ABORTOBJECT      9 /* Remote object aborted the link */
       #define DNSTAT_FAILED          38 /* Node or object failed */

       #define DNSTAT_NODERESOURCES   32 /* Node does not have sufficient resources for a new link */
       #define DNSTAT_OBJRESOURCES    33 /* Object does not have sufficient resources for a new link */
       #define DNSTAT_BADACCOUNT      36 /* The Account field in unacceptable */
       #define DNSTAT_TOOLONG         43 /* A field in the access control message was too long */

EXAMPLE

       Here  is an example MIRROR server. The real mirror server is built into dnetd.  This also illustrates the
       logging functions in libdnetd_daemon.

       #include <sys/types.h>
       #include <sys/socket.h>
       #include <stdarg.h>
       #include <syslog.h>
       #include <netdnet/dnetdb.h>
       #include <netdnet/dn.h>

       int main(int argc, char *argv[])
       {
           int insock;

           /* Set up logging. The parameters are:
            * daemon name to use
            * 's' means log to syslog
            */
           init_daemon_logging("mirror", 's');

           // Wait for something to happen (or check to see if it already has)
           insock = dnet_daemon(DNOBJECT_MIRROR, NULL, 0, 1);

           // Make sure we got a valid socket
           if (insock > -1)
           {
               int readnum;
               char condata[] = {0x00, 0x20}; // Actually 4096 as a LE word
               char ibuf[4096];

               /* We must accept the connection */
               dnet_accept(insock, 0, condata, 2);

               while ( (readnum=read(insock,ibuf,sizeof(ibuf))) > 0)
               {
                   ibuf[0]=0x01;
                   if (write(insock,ibuf,readnum) < 0)
                   {
                       DNETLOG((LOG_WARNING, "mirror, write failed: %m\n"));
                       close(insock);
                       break;
                   }
               }
               close(insock);
           }
           return 0;
       }

       To compile:
       gcc mirror.c -omirror -ldnet -ldnet_daemon -lcrypt

NAME

SYNOPSIS

DESCRIPTION

EXAMPLE

SEE ALSO