This MCI command message returns information about MCI devices. MCI supports this message directly rather than passing it to the devices. String information is returned in the application-supplied buffer pointed to by the lpstrReturn field of the data structure identified by lpSysInfo. Numeric information is returned as a DWORD placed in the application-supplied buffer. The dwReturnSize field specifies the buffer length.
DWORD dwFlags
The following standard and command-specific flags apply to all devices:
MCI_SYSINFO_INSTALLNAME
Obtains the name (listed in the SYSTEM.INI file) used to install the device.
MCI_SYSINFO_NAME
Obtains a device name corresponding to the device number specified in the dwNumberField of the data structure identified by lpSysInfo . If the MCI_SYSINFO_OPEN flag is set, MCI returns the names of open devices.
MCI_SYSINFO_OPEN
Obtains the quantity or name of open devices.
MCI_SYSINFO_QUANTITY
Obtains the number of devices of the specified type that are listed in the [mci] section of the SYSTEM.INI file. If the MCI_SYSINFO_OPEN flag is set, the number of open devices is returned.
LPMCI_SYSINFO_PARMS lpSysInfo
Specifies a far pointer to the MCI_SYSINFO_PARMS structure.
Returns zero if successful. Otherwise, it returns an MCI error code.
The wDeviceType element of the lpSysInfo structure is used to indicate the device type of the query. If the wDeviceID parameter is set to MCI_ALL_DEVICE_ID it will override the value of wDeviceType.
Integer return values are DWORDS returned in the buffer pointed to by the lpstrReturn field of MCI_SYSINFO_PARMS.
String return values are NULL-terminated strings returned in the buffer pointed to by the lpstrReturn field.