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       dnet_daemon, dnet_accept, dnet_reject - DECnet daemon functions


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

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


       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 */


       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)
                   if (write(insock,ibuf,readnum) < 0)
                       DNETLOG((LOG_WARNING, "mirror, write failed: %m\n"));
           return 0;

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


       dnetd(8),   dnet_addr(3),  dnet_ntoa(3),  dnet_conn(3),  getnodeadd(3),
       getnodebyname(3), getnodebyaddr(3), setnodeent(3), decnet.proxy(5)