DosQueryThreadAffinity
From EDM2
Contents
Description
DosQueryThreadAffinity allows a thread to inquire for the current thread's processor affinity mask and the system's capable processor affinity mask.
Syntax
APIRET DosQueryThreadAffinity (ULONG scope, PMPAffinity pAffinityMask)
Parameters
- scope(ULONG) input
AFNTY_THREAD Return the current threads processor affinity mask. AFNTY_SYSTEM Return the system's current capable processor affinity mask.
- pAffinityMask(PMPAffinity) input
- Address of MPAffinity structure to receive the affinity mask. Processors 0 31 are in mask [0] and processors 32 63 are in mask [1].
Return Code
ulrc APIRET) returns
DosQueryThreadAffinity returns one of the following values
- 13 ERROR_INVALID_DATA
- 87 ERROR_INVALID_PARAMETER
Remarks
DosQueryThreadAffinity allows a thread to ask the Processor Affinity Mask for
- The current thread's processor affinity mask, scope =AFNTY_THREAD, returns qwThreadAffinity, for the calling thread.
- The system's capable processor affinity mask, scope=AFNTY_SYSTEM, returns qwCapableAffinity for the system. The caller may then use any subset of the returned affinity mask to change the threads processor affinity in a later call to DosSetThreadAffinity.
Example Code
#define INCL_DOS#define INCL_32 #define INCL_DOSERRORS #define INCL_NOPMAPI #include os2.h> #include stdio.h> int main(void) { APIRET rc; MPAFFINITY affinity; rc = DosQueryThreadAffinity(AFNTY_SYSTEM, affinity); printf("Query system's affinity rc = %08.8xh\n",rc); printf("Query system's affinity affinity[0] = %08.8xh, affinity[1] = %08.8xh\n", affinity.mask[0], affinity.mask[1]); return rc; }