Gets the current default drive for the requesting process.

#define INCL_DOSFILEMGR
#include <os2.h>

PULONG    pdisknum;  /*  Address of the number of the default drive. */
PULONG    plogical;  /*  Address of the bit map where the system returns the mapping of the logical drives. */
APIRET    ulrc;      /*  Return Code. */

ulrc = DosQueryCurrentDisk(pdisknum, plogical);