mciQuerySysValue

This function queries the value of system-defined attributes.

Syntax

mciQuerySysValue(iSysValue, pValue)            

Parameters

iSysValue (USHORT) - input

Specifies the system attribute. The possible system attributes are:

MSV_CLOSEDCAPTION

Returns TRUE if the user has enabled closed captioning and FALSE otherwise.

MSV_MASTERVOLUME

The master volume setting. The range is 0 to 100.

MSV_HEADPHONES

Returns TRUE if the user has headphones enabled for the system and FALSE otherwise.

MSV_SPEAKERS

Returns TRUE if the user has speakers (line out) enabled for the system and FALSE otherwise.

MSV_WORKPATH

Points to a character buffer of size CCHMAXPATH. This is the name of the file-system path where temporary files created by OS/2 multimedia are located (for example, c:\mmos2\temp).

MSV_SYSQOSVALUE

System wide Quality of Service (QOS) specification value used for band-width reservation (for example, bytes per second) over the network.

MSV_SYSQOSERRORFLAG

Description of error occurring during band-width reservation.

pValue (PVOID) - in/out

Pointer to the return field. The type of data object this field points to is dependent on the attribute requested:

System Attribute

Data Type 
MSV_CLOSEDCAPTION   BOOL
MSV_MASTERVOLUME    ULONG
MSV_HEADPHONES    ULONG
MSV_SPEAKERS    ULONG
MSV_WORKPATH    PSZ
MSV_SYSQOSVALUE    ULONG
MSV_SYSQOSERRORFLAG    ULONG 

Return Code

rc (BOOL) - returns

If the command completes successfully then MCIERR_SUCCESS is returned, otherwise non-zero is returned.

Example Code

Declaration:

 
#define INCL_MCIOS2
#include <os2.h>

USHORT    iSysValue;  /*  System attribute. */
PVOID     pValue;     /*  Pointer to return field. */
BOOL      rc;         /*  Return code. */

rc = mciQuerySysValue(iSysValue, pValue);

The following code illustrates how to query a multimedia system value.

 
 
  #define INCL_MCIOS2
  #include <os2me.h>

  CHAR  szWorkPath[CCHMAXPATH];
  mciQuerySysValue(MSV_WORKPATH,  szWorkPath); /* Get temporary
                                                     file path.    */

Related Functions

• mciSetSysValue