Platform SDK: Network Management

NetServerDiskEnum

The NetServerDiskEnum function retrieves a list of disk drives on a server. The function returns an array of three-character strings (a drive letter, a colon, and a terminating null character).

Security Requirements

Only members of the Administrators or Account Operators local group can successfully execute the NetServerDiskEnum function on a remote computer. No special group membership is required for local calls.

NET_API_STATUS NetServerDiskEnum(
  LPWSTR servername,     
  DWORD level,           
  LPBYTE *bufptr,        
  DWORD prefmaxlen,      
  LPDWORD entriesread,   
  LPDWORD totalentries,  
  LPDWORD resume_handle  
);

Parameters

servername: [in] Pointer to a Unicode string specifying the name of the remote server on which the function is to execute. The string must begin with \\. If this parameter is NULL, the local computer is used.
level: [in] This parameter must be zero.
bufptr: [out] Pointer to the buffer that receives the data. The data is an array of three-character strings (a drive letter, a colon, and a terminating null character). This buffer is allocated by the system and must be freed using the NetApiBufferFree function. Note that you must free the buffer even if the function fails with ERROR_MORE_DATA.
prefmaxlen: [in] Specifies the preferred maximum length of returned data, in bytes. If you specify MAX_PREFERRED_LENGTH, the function allocates the amount of memory required for the data. If you specify another value in this parameter, it can restrict the number of bytes that the function returns. If the buffer size is insufficient to hold all entries, the function returns ERROR_MORE_DATA. For more information, see Network Management Function Buffers and Network Management Function Buffer Lengths.
entriesread: [out] Pointer to a DWORD value that receives the count of elements actually enumerated.
totalentries: [out] Pointer to a DWORD value that receives the total number of entries that could have been enumerated from the current resume position.
resume_handle: [in/out] Pointer to a DWORD value that contains a resume handle which is used to continue an existing server disk search. The handle should be zero on the first call and left unchanged for subsequent calls. If resume_handle is NULL, then no resume handle is stored.

Return Values

If the function succeeds, the return value is NERR_Success.

If the function fails, the return value can be one of the following error codes.

Value	Meaning
ERROR_ACCESS_DENIED	The user does not have access to the requested information.
ERROR_INVALID_LEVEL	The value specified for the level parameter is invalid.
ERROR_MORE_DATA	More entries are available. Specify a large enough buffer to receive all entries.
ERROR_NOT_ENOUGH_MEMORY	Insufficient memory is available.

Remarks

The following code sample demonstrates how to call the NetServerDiskEnum function to retrieve a list of disk drives on a server. The sample calls NetServerDiskEnum, specifying the information level 0 (required). If there are entries to return, and the user has access to the information, it prints a list of the drives, in the format of a three-character string: a drive letter, a colon, and a terminating null character. The sample also prints the total number of entries that are available and the number of entries actually enumerated. Finally, the code sample frees the memory allocated for the buffer.

#ifndef UNICODE
#define UNICODE
#endif

#include <stdio.h>
#include <assert.h>
#include <windows.h> 
#include <lm.h>

int wmain(int argc, wchar_t *argv[])
{
   const int ENTRY_SIZE = 3; // Drive letter, colon, NULL
   LPTSTR pBuf = NULL;
   DWORD dwLevel = 0; // level must be zero
   DWORD dwPrefMaxLen = -1;
   DWORD dwEntriesRead = 0;
   DWORD dwTotalEntries = 0;
   NET_API_STATUS nStatus;
   LPTSTR pszServerName = NULL;

   if (argc > 2)
   {
      fwprintf(stderr, L"Usage: %s [\\\\ServerName]\n", argv[0]);
      exit(1);
   }
   // The server is not the default local computer.
   //
   if (argc == 2)
      pszServerName = argv[1];
   //
   // Call the NetServerDiskEnum function.
   //
   nStatus = NetServerDiskEnum(pszServerName,
                               dwLevel,
                               (LPBYTE *) &pBuf,
                               dwPrefMaxLen,
                               &dwEntriesRead,
                               &dwTotalEntries,
                               NULL);
   //
   // If the call succeeds,
   //
   if (nStatus == NERR_Success)
   {
      LPTSTR pTmpBuf;

      if ((pTmpBuf = pBuf) != NULL)
      {
         DWORD i;
         DWORD dwTotalCount = 0;
         //
         // Loop through the entries.
         //
         for (i = 0; i < dwEntriesRead; i++)
         {
            assert(pTmpBuf != NULL);

            if (pTmpBuf == NULL)
            {
               // On a remote computer, only members of the
               //  Administrators or the Account Operators 
               //  local group can execute NetServerDiskEnum.
               //
               fprintf(stderr, "An access violation has occurred\n");
               break;
            }
            //
            // Print drive letter, colon, NULL for each drive;
            //   the number of entries actually enumerated; and
            //   the total number of entries available.
            //
            fwprintf(stdout, L"\tDisk: %S\n", pTmpBuf);

            pTmpBuf += ENTRY_SIZE;
            dwTotalCount++;
         }

         fprintf(stderr, "\nEntries enumerated: %d\n", dwTotalCount);
      }
   }
   else
      fprintf(stderr, "A system error has occurred: %d\n", nStatus);

   //
   // Free the allocated buffer.
   //
   if (pBuf != NULL)
      NetApiBufferFree(pBuf);

   return 0;
}

If you are programming for Active Directory, you may be able to call certain Active Directory Service Interface (ADSI) methods to achieve the same functionality you can achieve by calling the network management server functions. For more information, see IADsComputer.

Requirements