is the protocol between ddd and gdb documented on Linux?

Hello all,

My Debian 13 supplied ddd has version 3.3.12 (I am developing a GPL license=
d inference engine in C++ for Linux).

How does it communicate with GDB? where are documented the protocols for co=
mmunication
(e.g. difference with gdb -tui)

Can I use GDB-17.1 with ddd 3.3.12 or should I recompile ddd 3.4.1 from its=
 tarball?

See related questions https://sourceware.org/pipermail/gdb/2026-January/052=
030.html=20
& https://sourceware.org/pipermail/gdb/2026-January/052039.html
& https://sourceware.org/pipermail/gdb/2026-January/052067.html

Thanks

NB. I am also seeking help on design and implementations of open source inf=
erence engines in C++
--=20

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s
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