writeProt
DrvSts structure
#include <Disks.h>
typedef struct DrvSts { Size Offset Description
short track; 2 0 Current track
SignedByte writeProt; 1 2 Bit 7 is 1 if volume is locked
SignedByte diskInPlace; 1 3 Disk in place
SignedByte installed; 1 4 Drive installed
SignedByte sides; 1 5 Bit 7 is 0 is the disk is single-sided
QElemPtr qLink; 4 6 Address of next queue element
(0=last)
short qType; 2 10 Reserved
short dQDrive; 2 12 Drive number
short dQRefNum; 2 14 Drive reference number
short dQFSID; 2 16 File system identifier
SignedByte twoSideFmt; 1 18 -1 if double-sided disk
SignedByte needsFlush; 1 19 Reserved
short diskErrs; 2 20 Error count
} DrvSts; 22

Notes: This structure is used in the Disk Driver's DriveStatus call to return
information about the internal and external drives. The diskInPlace field is
0 when there is no disk and a 1 or a 2 for internal and external drives,
respectively. A value of -4 to -1 indicates that the disk was ejected in the
last one-and-a-half seconds. The installed field is 1 if the drive is
connected, -1 if not connected, and 0 if the drive might be connected. The
value for the twoSideFmt field is valid only if diskInPlace equals 2. The
count in diskErrs is incremented every time an error occurs internally
within the Disk Driver.