HP 3000 Manuals HP 3000 Manuals
Understanding Intrinsic Result Codes All the SNA IMF intrinsicsexcept VERS3270 return a code in the result parameter. Your program should always check the result parameter after it calls an intrinsic. A result parameter value of zero indicates that the intrinsic executed successfully. You might want to check for specific non-zero result values after certain intrinsic calls. The result values that each intrinsic can return are listed in the intrinsic descriptions in chapters 3 and 4. If any non-zero result values are important to your program, check for them after the result parameter is returned. For example, the RECV3270 intrinsic returns result = 24 if the receive timer expires before the host sends data. If your program calls RECV3270 and receives result = 24, it knows that the internal screen image has not been updated, and there is no new data from the host. Your program should specifically check whether result = 24 after a call to RECV3270 before it calls any intrinsics that read data from the internal screen image. If the result parameter returns a value that has no meaning at the current point in your program, regard it as an error and branch to your error handling routine. See appendix F, "Sample Programs," for examples of error checking and error handling using the result parameter.