MPE/iX Intrinsics Reference Manual (32650-90875)

Chapter 2 25
Intrinsic Use
Error Handling
Error Handling
Three types of errors can occur when an intrinsic is executed:
• Condition code errors. Such errors are generally recoverable since control returns to the
calling program. The operating system maintains condition codes to provide backward
compatibility with previous (MPE V/E-based) operating systems.
• Status parameter errors. When you include the
status parameter in the intrinsic call,
it returns status information to the calling routine. For some intrinsics, both the
condition code and the special status parameter can return information; other intrinsics
use only one of these to return information.
• Abort errors. Such errors occur when a calling program passes illegal parameters to an
intrinsic or does not have the required capability for the intrinsic. An abort error
terminates the process.
Condition Code Errors
Some intrinsics have an associated condition code. A condition code is a temporary value
providing information about what happened during execution. The condition code is
affected by many intrinsics and should be checked immediately upon return from an
intrinsic.
A condition code has three possible values (CCG, CCL, or CCE) and has the general
meaning as indicated in Table 2-3. Specific meanings are listed under the individual
intrinsic called.
Status Parameter Errors
Some intrinsics use the status parameter to return information on the status of the
intrinsic call. This parameter is a native mode (NM) implementation of the condition code
feature with extended capabilities. The
status parameter is a 32-bit signed integer value
passed by reference.
Table 2-3. Condition Code Descriptions
Value Condition
Code
Description
0 CCG (>) Condition Code Greater Than. A warning or special condition occurred
but may not have affected the execution of the request. (For example, the
request was executed, but default values were assumed as intrinsic call
parameters.)
1 CCL (<) Condition Code Less Than. The request was not granted, but the error
condition may be recoverable.
2 CCE (=) Condition Code Equal. Generally indicates that the request was granted.