Return to timer.c CVS log

Up to [OS/2 SDKs] / os2sdk / demos / examples / timer

Annotation of os2sdk/demos/examples/timer/timer.c, revision 1.1.1.2

1.1.1.2 ! root        1: /* This example illustrates the use of the following MS OS/2 functions:
        !             2:  *     DosTimerStart, DosTimerAsync, DosTimerStop, DosSleep
1.1       root        3:  *
1.1.1.2 ! root        4:  * Created by Microsoft Corp. 1986
1.1       root        5:  */
                      6: 
1.1.1.2 ! root        7: #define INCL_DOSPROCESS
        !             8: #define INCL_DOSDATETIME
        !             9: #define INCL_DOSSEMAPHORES
        !            10: 
        !            11: #include <os2def.h>
        !            12: #include <bsedos.h>
1.1       root       13: 
                     14: #define SEMNAME        "\\SEM\\SOMESEM"  /* name of semaphore */
                     15: #define TIMERINTERVAL 1000L    /* timer interval */
                     16: #define ASYNCINTERVAL 2000     /* asynchronous timer interval */
                     17: #define NOTIMEOUT -1           /* no timeout */
1.1.1.2 ! root       18: #define BEEPFREQUENCY 400      /* frequency parameter to DosBeep */
        !            19: #define BEEPDURATION  50       /* duration parameter to DosBeep */
1.1       root       20: 
                     21: main ()
                     22: {
1.1.1.2 ! root       23:        HSEM   SemHandle;         /* storage for semaphore handle */
        !            24:        HTIMER    TimerHandle;    /* handle returned by DosTimerStart*/
1.1       root       25: 
                     26:        /* create a system semaphore */
1.1.1.2 ! root       27:        DosCreateSem (CSEM_PUBLIC, &SemHandle, SEMNAME);
1.1       root       28: 
                     29:        /*
1.1.1.2 ! root       30:         * DosTimerStart/Stop - these functions provide a repetitive
1.1       root       31:         * asynchronous timer which clear a semaphore at a specified interval.
                     32:         */
                     33: 
1.1.1.2 ! root       34:        DosSemSet (SemHandle);          /* set the system semaphore */
1.1       root       35: 
                     36:        /* set the interval timer */
1.1.1.2 ! root       37:        DosTimerStart (TIMERINTERVAL, SemHandle, &TimerHandle);
1.1       root       38: 
                     39:        /* normally, application would do some work in here */
                     40: 
1.1.1.2 ! root       41:        DosSemWait (SemHandle, (long) NOTIMEOUT); /* wait on the semaphore */
        !            42:        DosBeep (BEEPFREQUENCY, BEEPDURATION);    /* beep when done */
        !            43:        DosTimerStop (TimerHandle);               /* stop the interval timer */
1.1       root       44: 
                     45:        /*
1.1.1.2 ! root       46:         * DosTimerAsync example. This function provides a one-shot
1.1       root       47:         * asynchronous timer which clears a specified semaphore after
                     48:         * a specified time delay.
                     49:         */
                     50: 
1.1.1.2 ! root       51:        DosSemSet (SemHandle);          /* set the system semaphore */
1.1       root       52: 
                     53:        /* start the asynchronous timer */
1.1.1.2 ! root       54:        DosTimerAsync ((long) ASYNCINTERVAL, SemHandle, &TimerHandle);
1.1       root       55: 
                     56:        /* normally, application would do some work in here */
                     57: 
1.1.1.2 ! root       58:        DosSemWait (SemHandle,  (long) NOTIMEOUT); /* wait on the semaphore */
        !            59:        DosBeep (BEEPFREQUENCY, BEEPDURATION);    /* beep when done */
1.1       root       60: 
                     61:        /*
1.1.1.2 ! root       62:         * DosTimerStop is used to cancel either type of timer. After using
1.1       root       63:         * this function you must put the semaphore back into a known state
                     64:         * if you need to use it again. Example of cancelling a timer:
                     65:         */
                     66: 
1.1.1.2 ! root       67:        DosSemSet (SemHandle);          /* set the system semaphore */
1.1       root       68: 
                     69:        /* start the asynchronous timer (specify a long time) */
1.1.1.2 ! root       70:        DosTimerAsync ((long) (10*ASYNCINTERVAL), SemHandle, &TimerHandle);
1.1       root       71: 
1.1.1.2 ! root       72:        DosTimerStop (TimerHandle);     /* stop the asynchronous timer */
        !            73:        DosSemClear (SemHandle);        /* clear the system semaphore */
        !            74:        DosCloseSem (SemHandle);        /* close the system semaphore */
1.1       root       75: 
                     76:        /*
1.1.1.2 ! root       77:         * DosSleep - simple synchronous suspend for specified interval.
1.1       root       78:         */
1.1.1.2 ! root       79:        DosSleep(TIMERINTERVAL);
        !            80:        DosBeep (BEEPFREQUENCY, BEEPDURATION);    /* beep when done */
1.1       root       81: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.