gtps2m3v | ACF/SNA Data Communications Reference |
You must use the CSNB segment to retrieve node control block (NCB) or scratch pad area (SPA) records in the applications that you develop. For more information refer to Allocating or Retrieving a Scratch Pad Area (SPA) for a Dynamic LU or Migration Guide. You can also use this segment to retrieve the following:
If an error occurs, you can return to the calling program or exit using the EXITC macro.
The CSNB segment is activated using the ENTRC macro.
Input requirements are as follows:
Register 1 must point to a 5-byte work area aligned on a halfword boundary. The format is: Bytes 0-1 Contains the 2-byte resource identifier (RID) for the requested NCB or SPA. 0-2 Contains the 3-byte resource identifier (RID) for the requested NCB or SPA. 3 Available data level for which the data record may be retrieved. This must be a multiple of 8. For example, X'00' means data level 0, X'08' means data level 1 and X'10' means data level 2, etc. 4 Option Byte Bit 0 = 0. The NCB is requested = 1. The SPA is requested 1 = 0. Retrieve the data record = 1. Return the file address of the data record (no retrieval is required). 2 = 0. Issue a FIWHC macro to retrieve the record = 1. Issue a FINWC macro to retrieve the record 3 = 0. Return to caller on an error condition 1. Issue EXITC on an error condition 4 = 0. Retrieve 2-byte RID from bytes 0-1. 1. Retrieve 3-byte RID from bytes 0-2. 5-7 Reserved and should be set to zero.
CNSB output is as follows: * Registers: R1 = 0 If the requested function was performed successfully = 1 If an error was encountered in calculating the file address of the record = 2 If an error was encountered on FINWC or FIWHC macro = 3 If the input parameter is invalid R1 - 5 = Same as on entry 6 - 7 = Contents unpredictable * Data Levels: CE1CRx = Address of the main storage block containing the requested data record CE1FAx = File address of the requested record * Entry Control Block Work Area EBX000 - EBX009 are used by this program CE1UR2 is the beginning of this program's save area for caller's registers 2 - 5