Using channels and containers in ECI V2 applications

You can use channels and containers when you connect to CICS® using the IPIC protocol. You must create a channel before it can be used in an ECI request.

1. Add the following code to your application program, to create a channel:

   ECI_ChannelToken_t chanToken;
   createChannel(&chanToken); 

2. You can add containers with a data type of BIT or CHAR to your channel. Here is a sample BIT container:

   int custNumber = 12345; 
   rc = ECI_createContainer(chanToken, "CUSTNO", ECI_BIT, 0, &custNumber, sizeof(custNumber)); 

   char custNumber[] = {0,1,2,3,4,5}; 	
   rc = ECI_createContainer(chanToken, "CUSTNO", ECI_BIT, 0, custNumber, 
   sizeof(custNumber));

   Here is a sample CHAR container that uses the CCSID of the channel:

   char * company = "IBM"; 	
   rc = ECI_createContainer(chanToken, "COMPANY", ECI_CHAR, 0, company, strlen(company)); 

   char * company = "IBM"; 	
   rc = ECI_createContainer(chanToken, "COMPANY", ECI_CHAR, 0, company, 
   strlen(company)); 

3. The channel can now be used in an ECI request, as the example shows:

   CTG_ECI_PARMS eciParms = {0};
   
   eciParms.eci_version = ECI_VERSION_2A;
   eciParms.eci_call_type = ECI_SYNC;
   strncpy(eciParms.eci_system_name, "CICSA", ECI_SYSTEM_NAME_LENGTH);
   eciParms.eci_userid_ptr = "USERNAME";
   eciParms.eci_password_ptr = "PASSWORD";
   strncpy(eciParms.eci_program_name, "CHANPROG", ECI_PROGRAM_NAME_LENGTH);
   eciParms.eci_extend_mode = ECI_NO_EXTEND;
   eciParms.channel = chanToken; 

4. When the request is complete, you can retrieve the current state of the containers in the channel, as the example shows:

   ECI_CONTAINER_INFO contInfo;
   
   rc = ECI_getFirstContainer(chanToken, &contInfo);
   
   while (rc == ECI_NO_ERROR) { 
       printf("Container %s\n", contInfo.name);  
   
       if (contInfo.type == ECI_BIT) { 
            printf("Type BIT\n"); 
       } else { 
            printf("Type CHAR\n"); 
       }  
   
       /* Read block of data into buffer */ 
       ECI_getContainerData(channelToken, contInfo.name, dataBuff, 
          sizeof(dataBuff), offset, &bytesRead);  
   
       rc = ECI_getNextContainer(chanToken, &contInfo); 
   }