UsbQueryNumberDevices
Description
Obtains the total number of currently attached USB devices.
Syntax
ulrc = UsbQueryNumberDevices(pulNumDev)
Parameters
- pulNumDev
- the address of the variable to receive the Total Number.
Return Code
0x0000 - NO_ERROR
Errors
0x0057 - ERROR_INVALID_PARAMETER 0x1B58 - USB_NOT_INIT 0xFF13 - ERROR_I24_INVALID_PARAMETER 0xFF1F - ERROR_GEN_FAILURE 0xFF57 - ERROR_INVALID_PARAMETER
Remarks
Example Code
//Code Snippet - UsbQueryNumberDevices
{
APIRET ulrc;
PULONG pulNumDev;
ULONG ulNumDev;
pulNumDev = &ulNumDev;
ulrc = UsbQueryNumberDevices(pulNumDev);
printf("\nUsbQueryNumberDevices - ulrc: 0x%04X (%hu)",ulrc,ulrc);
if (!ulrc) //success
{
printf(" - NumberDevices: %hu",ulNumDev);
}
}