# ILockBytes::SetSize

Changes the size of the byte array.

HRESULT SetSize(

ULARGE_INTEGER cb | //Specifies the new size of the byte array in bytes
); |

Parameter

cb
  [in]Specifies the new size of the byte array as a number of bytes.

Return Values

S_OK
  The size of the byte array was successfully changed.
STG_E_ACCESSDENIED
  The caller does not have permission to access the byte array.
STG_E_MEDIUMFULL
  The byte array size is not changed because there is no space left on the storage device.

Remarks

ILockBytes::SetSize changes the size of the byte array. If the cb parameter is larger than the current byte array, the byte array is extended to the indicated size by filling the intervening space with bytes of undefined value, as does ILockBytes::WriteAt, if the seek pointer is past the current end-of-stream.

If the cb parameter is smaller than the current byte array, the byte array is truncated to the indicated size.

#### Notes to Callers

Callers cannot rely on STG_E_MEDIUMFULL being returned at the appropriate time because of cache buffering in the operating system or network. However, callers must be able to deal with this return code because some ILockBytes implementations might support it.

See Also

ILockBytes::ReadAt, ILockBytes::WriteAt, ILockBytes&emdash;File-Based Implementation, ILockBytes&emdash;Global Memory Implementation