Purpose

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].

Returns

ulrc APIRET) returns

Return Code.

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.

Related Functions

• 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;
}

---

[Back] [Next]