Is there interest in undocumented API definitions for dlls other than ntdll ? (e.g, user32, gdi32, etc)

[440bx]

The title says it (or asks it) all.

[diversenok]

Sure, at least to some extent. You can already find some non-ntdll function definitions in ntmisc.h, winsta.h, subprocesstag.h, ntsam.h, ntbcd.h, ntuser.h, and usermgr.h. As a general rule, when choosing between alternatives, lower-level APIs take precedence. This is due to the nature of the project and an explicit choice to avoid unnecessary dependencies and abstraction layers on the API side. Of course, it only fully applies if the higher-level API cannot offer advantages (aside from potentially simplifying invocation) over the lower-level one. Example: there is no point in using EnumProcesses when we have NtQuerySystemInformation (i.e., it brings no added value), but it's not practical to replace CreateProcess with NtCreateUserProcess because maintaining compatibility with all its features is not feasible/possible.

As for user32 and gdi32 specifically, you can see that ntuser.h defines some APIs from there. NtUser* and NtGdi* functions from win32u.dll might be more interesting than the corresponding wrappers from user32.dll/gdi32.dll from the low-level perspective, but they are unavailable on older versions. And, either way, user32 is not a dependency that is feasible to drop. So both can come in handy.

[440bx]

Thank you, that makes things clear.

I asked because I may be able to contribute a few definitions for other dlls sometime in the future.