gpi12.hlp (Table of Contents; Topic list)
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DevQueryDeviceNames (1.2)
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#define INCL_DEV
 
BOOL DevQueryDeviceNames(hab, pszDriverName, pdn, achDeviceName,
    achDeviceDesc, pdt, achDataType)
HAB hab;                 /* anchor-block handle                      */
PSZ pszDriverName;       /* pointer to string for device driver name */
PLONG pdn;               /* maximum number of device names           */
PSTR32 achDeviceName;    /* pointer to array of device names         */
PSTR64 achDeviceDesc;    /* pointer to array of device descriptions  */
PLONG pdt;               /* maximum number of data types             */
PSTR16 achDataType;      /* pointer to array of data types           */
 
The DevQueryDeviceNames function returns the device names, descriptions, and
data types supported by the specified device driver.
 
The application can call the function first with the pdn and pdt parameters
set to zero in order to find how much storage is needed for the data
buffers. Having allocated the storage, the application then calls the
function a second time in order to have the buffers filled with data for the
data to be filled in.
 
Parameter      Description
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hab            Identifies the anchor block.
 
pszDriverName  Points to the null-terminated string that contains the name
               of the device driver.
 
pdn            Points to the maximum number of device names and descriptions
               that can be returned. If this parameter is zero, the number
               of device names and descriptions supported is returned and
               the arrays pointed to by the achDeviceName and achDeviceDesc
               parameters are not updated. If this parameter is nonzero,
               then its value is updated to the number returned in the
               arrays pointed to by achDeviceName and achDeviceDesc and the
               arrays are updated.
 
achDeviceName  Points to an array of null-terminated ASCII strings, each
               element of which identifies a particular device (for example,
               model number). Valid names are defined by device drivers.
               IBM4201 is an example of a device name.
 
achDeviceDesc  Points to an array of null-terminated ASCII strings, each
               element of which is a description of a particular device (for
               example, model name). Valid names are defined by device
               drivers. IBM 4201 Proprinter is an example of a device
               description.
 
pdt            Points to the maximum number of data types that can be
               returned. If this parameter is zero, the number of data types
               supported is returned and the array pointed to by the
               achDataType parameter is not updated. If this parameter is
               nonzero, then its value is updated to the number returned,
               and the array is updated.
 
achDataType    Points to an array of null-terminated ASCII strings, each
               element of which identifies a data type. Valid data types are
               defined by device drivers.
 
Return Value
 
The return value is TRUE if the function is successful or FALSE if an error
occurs.
 
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