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_getdrives

Returns a bitmask representing the currently available disk drives.

unsigned long _getdrives( void );

Return Value

If the function succeeds, the return value is a bitmask representing the currently available disk drives. Bit position 0 (the least-significant bit) is drive A, bit position 1 is drive B, bit position 2 is drive C, and so on. If the function fails, the return value is zero. To get extended error information, call GetLastError.

Requirements

Routine

Required header

_getdrives

<direct.h>

For more compatibility information, see Compatibility in the Introduction.

Example

// crt_getdrives.c
// This program retrives and lists out
// all the logical drives that are 
// currently mounted on the machine.

#include <windows.h>
#include <direct.h>
#include <stdio.h>
#include <tchar.h>

TCHAR g_szDrvMsg[] = _T("A:\n");

int main(int argc, char* argv[]) {
   ULONG uDriveMask = _getdrives();

   if (uDriveMask == 0)
   {
      printf( "_getdrives() failed with failure code: %d\n",
              GetLastError());
   }
   else
   {
      printf("The following logical drives are being used:\n");

      while (uDriveMask) {
         if (uDriveMask & 1)
            printf(g_szDrvMsg);

         ++g_szDrvMsg[0];
         uDriveMask >>= 1;
      }
   }
}

The following logical drives are being used:
A:
C:
D:
E:

NET Framework Equivalent

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

See Also

Concepts

Directory Control