16 марта 2019 г., в 8:30, Eli Zaretskii <eliz@gnu.org> написал(а):

From: Evgeny Zajcev <lg.zevlg@gmail.com>

Date: Fri, 15 Mar 2019 23:52:17 +0300

There is no possibility to create unibyte strings from emacs modules in order to create some binary data

representation

The only solution for now is to call `make_string` method and then apply `encode-coding-string' with utf-8

encoding to the result.  But on large data this became very slow

I used this patch to bypass the conversion steps and it works pretty nice

Ideally I would like to use user-ptr objects as `:data' in image specification, but solution with `make_data'

module method will be suitable enough

Please explain why you need to create a unibyte string for that.  I
guess what's missing is more details regarding what you are trying to
do (the single sentence above about :data wasn't enough for me), and
how is your module involved in that, in particular why do you need a
module to display an image in Emacs.