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The minimal size of the vmware disk is 100mb. In some cases, the size is too big, maybe we need a smaller disk.

First, using vmware-vdiskmanager to get the template of the vmware disk descriptor file.

 vmware-vdiskmanager.exe -c -s 100mb -a ide -t 2 100mb.vmdk

100mb.vmdk

 # Disk DescriptorFile
 version=1
 CID=ef8424cf
 parentCID=ffffffff
 createType="monolithicFlat"
 # Extent description
 RW 204800 FLAT "100mb-flat.vmdk" 0

The total size is 204800 sectors, 102400KB. Disk type is FLAT, preallocated, its name is 100mb-flat.vmdk.

 # The Disk Data Base 
 #DDB
 ddb.virtualHWVersion = "6"
 ddb.geometry.cylinders = "203"
 ddb.geometry.heads = "16"
 ddb.geometry.sectors = "63"
 ddb.adapterType = "ide"

The CHS is 203/16/63, adapter is IDE.

Now, modify the descriptor file, change the size to 65536

 RW 65536 FLAT "32mb-flat.vmdk" 0

change the CHS

 ddb.geometry.cylinders = "64"
 ddb.geometry.heads = "16"
 ddb.geometry.sectors = "63"

The last job is creating the file '32mb-flat.vmdk' by 'dd'

 dd if=/dev/zero of=32mb-flat.vmdk bs=1m count=32

or by this program

  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  
  #define M (1024*1024)
  
  int main(int argc, char* argv[])
  {
      int size;
      char *buf;
      FILE *fp;
      int i;
      
      if (argc == 3)
          size = atoi(argv[2]);
      else
          size = 10;
  
      buf = (char *)malloc(M);
      if (!buf) {
          printf("out of memory\n");
          return -1;
      }
      memset(buf, 0, M);
      fp = fopen(argv[1], "wb");
      if (!fp) {
          printf("Can't create: %s\n", argv[1]);
          free(buf);
          return -1;
      }
      for (i = 0; i < size; i++)
          fwrite(buf, M, 1, fp);
      
      fclose(fp);
      free(buf);
      return 0;
  }

Finished!