AppleTalk / C Programming Problem

[Peter A. Steinauer]

Ok everyone, I have a problem that I'm hoping someone can help me out with...
	I'm trying to write a simple program which will compose a packet 
	and send it from one socket to another on the same machine (or to
	a socket on a different machine)... I'm able to open both the source
	and desination sockets but when I try to compose and send the packet
	DDPWrite returns a -91 in errCode which is supposed to say that the 
	source socket isn't open... I don't understand... Could some one 
	take a look at the following code and let me know what I'm missing.
	I would really appreciate it...

		Pete Steinauer
			University of Colorado Boulder

**********


/*
 * Simple appletalk tester... This program should open up two ddp sockets
 *	one which it will use to send a packet from and another one to send
 * 	a packet to.
 */

#include <MemoryMgr.h>
#include <AppleTalk.h>
#include <nAppleTalk.h>
#include <stdio.h>
#include <string.h>

#define	FALSE	0
#define TRUE	1

ABRecHandle		myABRecHandle;
ABRecPtr		myABRecPtr;
ABusRecord		myABRecord;
unsigned char		mySocketsource, mySocketdest;
char			myBuffer[600];
char			someText[255] = "This is a sample datagram";
int 			errCode, dataLen, index;
unsigned int		async, retCksumErrs, doChecksum;

main()
{
	int	myNode, myNet;

/* Open up AppleTalk */	
errCode = MPPOpen();

/* if there was an opening error then print an error... Otherwise go on to other work */ 
if (errCode != noErr)
	printf("Error in opening AppleTalk\n");
  else
  	{
	/* Get the node number and net number */
  	errCode = GetNodeAddress(&myNode, &myNet);
  	if (errCode != noErr)
  		printf("Error in getting the node address \n");
  	else
  		printf("Node Number: %d   Net Number: %d\n", myNode, myNet);
  		
	/* Open up necessary sockets */
  	mySocketsource = 77;
  	mySocketdest = 78;
  	errCode = DDPOpenSocket(&mySocketsource, NULL);
  	printf("Source Socket number is %d\n",mySocketsource);
  	printf("errCode is %d\n",errCode);
  	errCode = DDPOpenSocket(&mySocketdest, NULL);
  	printf("Destination Socket number is %d\n",mySocketdest);
  	printf("errCode is %d\n",errCode);
  
  	if (errCode != noErr)
  		printf("Error opening socket...\n");
  	else
  		{
		/* Prepare packet to be sent */

  		myABRecPtr = &myABRecord;
  		myABRecHandle = & myABRecPtr;
  	
  		dataLen = strlen(someText);
  		strcpy(myBuffer, someText);
  		
  		async = FALSE;
  		
  		myABRecord.ddpProto.ddpType = 5;
  		myABRecord.ddpProto.ddpSocket = mySocketsource;
  		myABRecord.ddpProto.ddpAddress.aNet=myNet;
  		myABRecord.ddpProto.ddpAddress.aNode=myNode;
  		myABRecord.ddpProto.ddpAddress.aSocket = mySocketdest;
  		myABRecord.ddpProto.ddpReqCount = dataLen;
  		myABRecord.ddpProto.ddpDataPtr = myBuffer;
  		
  		doChecksum = FALSE;
  		
		/* Try to send packet....*/
  		errCode = DDPWrite(myABRecHandle, doChecksum, async);
  		
		/* Print out resultant error code */
  		printf("errCode = %d\n",errCode);
		}
	}
}