(_hg_operator_real_readstring): implemented. (_hg_operator_real_read): check the return value and raise /ioerror as needed. (_hg_operator_real_readhexstring): likewise. (_hg_operator_real_readline): likewise.
(_hg_operator_real_readstring): implemented.
(_hg_operator_real_read): check the return value and raise /ioerror as needed.
(_hg_operator_real_readhexstring): likewise.
(_hg_operator_real_readline): likewise.

freedesktop-unofficial-mirror/hieroglyph,freedesktop-unofficial-mirror/hieroglyph,freedesktop-unofficial-mirror/hieroglyph