[MarcZX10]

What

Carry screamm's explicitly offered wide-conversion implementation from issue #3077. It adds _WStoul, _Iswctype and swscanf_s, with focused tests for wide classification, conversion errors and secure wide scanning. The original source commits and author attribution are preserved. This branch includes the prerequisite fix from PR #3082; it depends on that PR.

Tested

The contributor reports Windows 11 Pro 26220 / WinLibs MinGW-w64 GCC 15.2.0 / Release full build including libs; guest_wide_conversion, guest_math, guest_wide_strings, guest_rune_locale, guest_scan_count and guest_wide_formatting passed 3/3, and ctest -j8 -E "^agc_|video_out" passed 389/389. Linux runtime tests were not reported. In this session, conventions and git diff --check passed; the local full CMake configure was blocked by the unavailable pinned SDL2 submodule commit.

Checklist

• Based on current main; no other open PR implements the same functions
• One topic per PR; follow-ups go in a new PR
• No comments in code except technical debt
• Unimplemented paths throw (NotImplemented_nid_no_patch); silent stubs are listed in TechnicalDebt
• No notes, investigation .md files or images added to the repository
• New third-party code is a submodule built from source
• Generic behaviour, not specific to one title
• Depends on: fix(libc): handle bare hexadecimal prefixes on Windows #3082
• AI-assisted: yes

[github-actions]

Progress report (262c031 → 51fca3c)

📈 System libraries: 84.53% (+0.09%, +3 implemented functions)

✅ 3 implemented

Library	Name
libc	_Iswctype_nid_postfix
libc	_WStoul_nid_postfix
libc	swscanf_s_nid_postfix

[github-actions]

Other open pull requests touch the same code. Merging one will break the other, or both implement the same thing. If this one builds on them, list them in Depends on.

Pull request	Conflicting files (lines on main)	Same exports	Same new files
#2651		swscanf_s_nid_postfix

[adriadam10]

Checked the three exports against the C11 rules and the Dinkumware xwcc.h class numbering; guest_math and guest_wide_conversion pass on Linux, and the new test target does not build without the change. The TechnicalDebt entry lists the unverified choices (class numbering on the console's libc.prx, unsigned int size argument). Merging.

This branch includes the strtol fix from #3082, so that PR is covered by this one.