#include <stdio.h>
#include <dos.h>

void main()
  {
    unsigned drive1, drive2, total;

    _dos_getdrive( &drive1 );
    printf( "Current drive is %c\n", 'A' + drive1 - 1 );
    /* try to change to drive C */
    _dos_setdrive( 3, &total );
    _dos_getdrive( &drive2 );
    printf( "Current drive is %c\n", 'A' + drive2 - 1 );
    /* go back to original drive */
    _dos_setdrive( drive1, &total );
    _dos_getdrive( &drive1 );
    printf( "Current drive is %c\n", 'A' + drive1 - 1 );
    printf( "Total number of drives is %u\n", total );
  }