Removable Media (Device-Driver Function 0Fh)

REMOVEMEDIAREQUEST STRUC

rmrLength db ? ;length of record, in bytes

rmrUnit db ? ;unit number

rmrFunction db 0Fh ;function number

rmrStatus dw ? ;status

rmrReserved db 8 dup(?) ;reserved

REMOVEMEDIAREQUEST ENDS

Removable Media (Device-Driver Function 0Fh) specifies whether a drive contains a removable medium.

This function is used for block-device drivers only.

Fields

rmrLength

Specifies the length, in bytes, of the REMOVEMEDIAREQUEST structure.

rmrUnit

Specifies the device to check for removable media.

rmrFunction

Specifies the Removable Media function: 0Fh.

rmrStatus

Specifies the status of the completed function. If the disk in the specified drive is removable, the busy bit (bit 9) must be zero. If the disk is not removable, the driver must set the busy bit. In both cases, the driver must set the done bit (bit 8).

rmrReserved

Reserved; do not use.

Comments

MS-DOS calls Removable Media only if bit 11 is set in the dhAttributes field of the driver's DEVICEHEADER structure. For a full description of the DEVICEHEADER structure, see Section 9.9, “Structures.”

Since MS-DOS assumes this function is always successful, it ignores any error value the function returns.