═══ 1. DosTmrQueryTime ═══

Queries the performance timer for a time value. Calling Sequence 

DosTmrQueryTime (pqwTime) 

Parameters 

pqwTime (@OTHER) - A pointer, supplied by the calling application, to the 
following structure: 

   typedef struct _QWORD {
      ULONG ulLo,
      ULONG ulHi,
   } QWORD;
   typedef QWORD *PQWORD;

Returns 

o No Error 
o ERROR_INVALID_PARAMETER - The QWORD structure could not be written to. 
o ERROR_TMR_NO_DEVICE - This indicates that the timer device driver was not 
  installed 
o ERROR_DEVICE_IN_USE - This indicates that there are multiple processes 
  attempting to use the 8254 hardware device in a conflicting manner. 
o ERROR_TMR_INVALID_TIME 

Remarks 

This API will fill the QWORD structure, supplied by the caller, with the 64-bit 
timer value such that : 

   pqwTime->ulHi = The most significant 32-bits of the timer value. 

   pqwTime->ulLo = The least significant 32-bits of the timer value. 

The performance timer is a free running counter; it is initialized to 0 at boot 
time and thereafter increments.  When it reaches its maximum value of (2к64 - 
1), it rolls over to 0 and continues incrementing.  A process can time an event 
by subtracting the value of the timer at the start of the event from the value 
of the timer at the end of the event.  Currently, ulTimerFreq = 1.19318 Mhz, 
for a timer resolution of about .838 microseconds.  (See also DosTmrQueryFreq.) 


═══ 2. DosTmrQueryFreq ═══

Queries the performance timer for its frequency. 

Calling Sequence 

DosTmrQueryFreq (pulTmrFreq) 

Parameters 

pulTmrFreq (@DWORD) - A pointer, supplied by the the calling application, to a 
ULONG which is to be filled with the timer frequency. 

Returns 

o No Error 
o ERROR_INVALID_PARAMETER - The parameter could not be written to. 
o ERROR_TMR_NO_DEVICE - This indicates that the timer device driver was not 
  installed 
o ERROR_DEVICE_IN_USE - This indicates that there are multiple processes 
  attempting to use the 8254 hardware device in a conflicting manner. 

Remarks 

Currently, the timer frequency = 1.19318 Mhz, for a timer resolution of about 
.838 microseconds. (See also DosTmrQueryTime.) 


═══ 3. Samples ═══

  /*
  * Description: Display high resolution system time.
  *
  *
  */

 #define INCL_DOS
 #define INCL_DOSERRORS

 #include <os2.h>
 #include <stdio.h>

 VOID
 main()
 {
   QWORD qwTime;
   ULONG rc;

     if ((rc = DosTmrQueryTime(&qwTime)) != NO_ERROR)
         printf("\nERROR (DosTmrQueryTime): %d\n", rc);
     else
         printf("Time = 0x %08lx %08lx\n",
             qwTime.ulHi, qwTime.ulLo);

 }