* src/estream.c (X_SHARE_RW): Replace by ...
(X_SHARE_CUSTOM,X_SHARE_READ,X_SHARE_WRITE,X_SHARE_DEL): new.
(func_file_create_w32): Set share_mode accordingly.
(parse_mode): Extend the "share" keyword.
* src/gpg-error.c (main): Add option --openmode to allow testing of
the share modes.