ms_getevt( )

---

Cautions | Errors | Example | See Also

Name:	int ms_getevt (devh, eblkp, timeout)
Inputs:	int devh	MSI device handle
	EV_EBLK * eblkp	pointer to event block
	int timeout	timeout value
Returns:	0 on success -1 on failure
Includes:	srllib.h dtilib.h msilib.h
Category:	Configuration
Mode:	synchronous
Platform:	DI, HDSI, Springware

Description

The ms_getevt( ) function is supported under Windows only. It blocks and returns control to the application for a specified event. This happens after one of the unsolicited events set by ms_setevtmsk( ) occurs on the station device specified by the devh parameter or if a timeout occurs.

Parameter	Description
devh	the valid device handle returned by a call to ms_open( )
evtblkp	pointer to the event that ended the blocking
timeout	the maximum amount of time to wait for an event to occur. If timeout is set to -1, the ms_getevt( ) function does not timeout and blocks until an event occurs. If timeout is set to 0 and an event is not present, the function returns immediately with a -1 return code.

On successful return from the function, the event block structure, EV_EBLK, will have the following information:

ev_dev

The device on which the event occurred. This is the same as the devh passed to the function.

ev_event

MSEV_SIGEVT indicating signaling transition event.

ev_data

An array of bytes where ev_data[0] and ev_data[1] contain the signaling information. Signaling information is retrieved in short variable. Refer to the example below for information on retrieving this data.

The event block structure is defined as follows:

typedef struct ev_eblk {
      int ev_dev;                 /* Device on which event occurred */
      unsigned long ev_event;     /* Event type */
      int ev_len;                 /* Length of data associated with event */
      unsigned char ev_data[8];   /* 8 byte data buffer */
      void ev_datap;              /* variable pointer if more than 8 bytes of data */
} EV_EBLK;  

Cautions

• The ms_getevt( ) function is not supported under the Linux operating system.
• This function fails when:
  • The device handle is invalid for an MSI device
  • The event field is invalid

Errors

If this function returns -1 to indicate failure, obtain the reason for the error by calling the SRL standard attribute function ATDV_LASTERR( ) or ATDV_ERRMSGP( ) to retrieve either the error code or a pointer to the error description, respectively.

Refer to the error type tables found in Chapter 5, "Error Codes". Error defines can be found in dtilib.h or msilib.h.

Example

#include <windows.h>
#include <errno.h>
#include "srllib.h"
#include "dtilib.h"
#include "msilib.h"  
EV_EBLK eblk;  
main()
{
   int devh;                 /* Board device handle */
   unsigned short sigmsk = MSMM_ONHOOK | MSMM_OFFHOOK | MSMM_HOOKFLASH;
   short sig;  
  /*
   * Open station 1 device
   */  
   if ((devh = ms_open("msiB1C1",0)) == -1) {
      printf("Error: Cannot open board 1 station 1. errno = 0x%x\n",errno);
      exit(1);
   }  
   if (ms_setevtmsk(devh, MSEV_SIG, sigmsk, DTA_SETMSK) == -1) {
       printf("%s: ms_setevtmsk MSEV_SIGMSK DTA_SETMSK ERROR %d: %s:Mask = 0x%x\n",
                   ATDV_NAMEP(devh),ATDV_LASTERR(devh),ATDV_ERRMSGP(devh),sigmsk);
       ms_close(devh);
       exit(1);
   }  
   /*
    *  Wait for events on this time slot
    */
   while(1) {
      ms_getevt ( devh, &eblk, -1 );    /* Wait forever */
      if (eblk.ev_event == MSEV_SIGEVT) {
         sig = eblk.ev_data[0]  |   (short) eblk.ev_data[1] << 8 ;
         if ((sig & MSMM_ONHOOK) == MSMM_ONHOOK)
             printf("Onhook signal received\n");
         if ((sig & MSMM_OFFHOOK) == MSMM_OFFHOOK)
             printf("Offhook signal received\n");
         if ((sig & MSMM_HOOKFLASH) == MSMM_HOOKFLASH)
             printf("Hook flash signal received\n");
      }
   } /* end of while statement */
}  

See Also

• ms_getevtmsk( )

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