Reads the contents of a BSTR into an AutoIt string.
_SysReadString($pBSTR [, $iLen = -1])
| $pBSTR | Pointer to the BSTR to read. |
| $iLen | (Optional) Length of the string to read (default: -1, reads entire string). |
| Success: | The string contents of the BSTR. |
| Failure: | Empty string, with @error set to: 1 - Invalid BSTR pointer. 2 - Invalid string length or empty BSTR. |