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;/* broker.c - Simple skeletal example of opening a broker compiled with SAS/C 6.56
slink FROM LIB:c.o,broker.o TO broker LIBRARY LIB:sc.lib,LIB:amiga.lib
Copyright (c) 1991-1999 Amiga, Inc.

This example is provided in electronic form by Amiga, Inc.
for use with the Amiga Mail Volume II technical publication.
Amiga Mail Volume II contains additional information on the correct
usage of the techniques and operating system functions presented in
these examples.  The source and executable code of these examples may
only be distributed in free electronic form, via bulletin board or
as part of a fully non-commercial and freely redistributable
diskette.  Both the source and executable code (including comments)
must be included, without modification, in any copy.  This example
may not be published in printed form or distributed with any
commercial product. However, the programming techniques and support
routines set forth in these examples may be used in the development
of original executable software products for Amiga

All other rights reserved.

This example is provided "as-is" and is subject to change; no
warranties are made.  All use is at your own risk. No liability or
responsibility is assumed.

#include <exec/libraries.h>
#include <libraries/commodities.h>
#include <dos/dos.h>
#include <clib/exec_protos.h>
#include <clib/alib_protos.h>
#include <clib/alib_stdio_protos.h>
#include <clib/commodities_protos.h>

#ifdef LATTICE
int CXBRK(void) { return(0); }  /* Disable Lattice CTRL/C handling */
int chkabort(void) { return(0); }

struct Library *CxBase;

void main(void);
LONG ProcessMsg(void);

CxObj *broker;

struct MsgPort *broker_mp;

struct NewBroker newbroker = {
    NB_VERSION, /* nb_Version - Version of the NewBroker structure */
    "AmigaMail broker", /* nb_Name - Name CX uses to identify this commodity */
    "Broker",   /* nb_Title - Title of commodity that appears in CXExchange */
    "A simple example of a broker",  /* nb_Descr - Description of the commodity */
    0,          /* nb_Unique - Tells CX not to launch new commodity with same name */
    0,          /* nb_Flags - Tells CX if this commodity has a window */
    0,          /* nb_Pri - This commodity's priority */
    0,          /* nb_Port - MsgPort CX talks to */
    0           /* nb_ReservedChannel - reserved for later use */

ULONG cxsigflag;

void main()
    /* Before bothering with anything else, open the library */
    if (CxBase = OpenLibrary("commodities.library", 37L))
        /* Commodities talks to a Commodities application through
         * an Exec Message port, which the application provides
        if (broker_mp = CreateMsgPort())
            newbroker.nb_Port = broker_mp;

            /* The commodities.library function CxBroker() adds a
             * broker to the master list.  It takes two arguments,
             * a pointer to a NewBroker structure and a pointer to
             * a LONG.  The NewBroker structure contains information
             * to set up the broker.  If the second argument is not
             * NULL, CxBroker will fill it in with an error code.
            if (broker = CxBroker(&newbroker, NULL))
                cxsigflag = 1L << broker_mp->mp_SigBit;

                /* After it's set up correctly, the broker
                 * has to be activated
                ActivateCxObj(broker, 1L);

                /* the main processing loop */
                while (ProcessMsg());

                /* It's time to clean up.  Start by removing
                 * the broker from the Commodities master list.
                 * The DeleteCxObjAll() function will take care
                 * of removing a CxObject and all those connected
                 * to it from the Commodities network

LONG ProcessMsg(void)
    CxMsg *msg;

    ULONG sigrcvd, msgid, msgtype;
    LONG returnvalue = 1L;

    /* wait for something to happen */
    sigrcvd = Wait(SIGBREAKF_CTRL_C | cxsigflag);

    /* process any messages */
    while(msg = (CxMsg *)GetMsg(broker_mp))
        /* Extract necessary information from the CxMessage and return it */
        msgid = CxMsgID(msg);
        msgtype = CxMsgType(msg);
        ReplyMsg((struct Message *)msg);

            case CXM_IEVENT:
                /* Shouldn't get any of these in this example */
            case CXM_COMMAND:
                /* Commodities has sent a command */
                printf("A command: ");
                    case CXCMD_DISABLE:
                        /* The user clicked Commodities Exchange disable
                         * gadget better disable
                        ActivateCxObj(broker, 0L);
                    case CXCMD_ENABLE:
                        /* user clicked enable gadget */
                        ActivateCxObj(broker, 1L);
                    case CXCMD_KILL:
                        /* user clicked kill gadget, better quit */
                        returnvalue = 0L;
                printf("Unknown msgtype\n");

    /* Test to see if user tried to break */
    if (sigrcvd & SIGBREAKF_CTRL_C)
        returnvalue = 0L;
        printf("CTRL C signal break\n");

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