fix(libc): export daemon

[Get-fix]

What

VLC (PPSA85300) imports daemon (Wn6I3wVATUE) and fails to load because no library exports it. It reaches this stop after execvp (#2827) and dup2 (#2478). Forking into the background is not supported, so daemon throws daemon: forking into the background not implemented. VLC 3.0 calls it only when its daemon option is set (libvlc.c), and the title starts libVLC with --ignore-config and without --daemon (player.cc). The new guest_daemon test checks the throw.

Tested

Windows 11 (WinLibs GCC 15.2.0 r7), Release, full build with BUILD_TESTING=ON on main 57f96fd:

• guest_daemon passes 5/5. With a silent return -1 or a different message planted, it fails.
• All 44 libc tests that build on Windows pass.
• tools/check_conventions.py and tools/check_test_registration.py pass.
• VLC v0.3 (catalog sha256), with the same converted executable and two fully rebuilt library sets whose sources differ only by this change, two runs each: with main + the execvp branch + feat(libkernel): implement dup and dup2 #2478 it stops at FAIL: unresolved ELF import Wn6I3wVATUE from libSceLibcInternal.prx (daemon); with this change as well it stops at FAIL: unresolved ELF import 5G2ONUzRgjY from libSceLibcInternal.prx (memrchr, feat(libc): implement memrchr #1592, feat(libSceLibcInternal): implement memrchr #1906 and feat(libc): add BSD string and memory helpers #2277 closed).

Not tested on Linux. The same branch and results are posted in #1578.

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 (attach them to this PR)
• New third-party code is a submodule built from source
• Generic behaviour, not specific to one title
• Depends on: none
• AI-assisted: yes (Claude Code)

🤖 Generated with Claude Code

[github-actions]

Thank you for your interest in the project! We are sorry, but we cannot accept more PRs while we work through the existing backlog. This PR has been automatically closed and labeled "intake paused". This is not a judgment of the quality of your changes.

[github-actions]

Progress report (2a4e03c → 520b9fa)

📉 System libraries: 85.8% (-0.03%, +1 declared functions)

🆕 1 declared as stubs

Library	Name
libc	daemon_nid_postfix

[oneandonlydean]

Reopened. Conflict in core/libs/prx/libc/CMakeLists.txt. Can you rebase?

[adriadam10]

Rebased onto main (conflict with the neighbouring test block in core/libs/prx/libc/CMakeLists.txt, kept both).

Checked on Linux: guest_daemon passes; without the change it does not link (daemon_nid_postfix missing). The thrown message matches NotImplemented_nid_no_patch, and the TechnicalDebt line sits under "Functional". Merging once CI is green.

[adriadam10]

Rebased onto main again (conflict with the neighbouring guest_memrchr test block in core/libs/prx/libc/CMakeLists.txt, kept both).

Re-checked on Linux: guest_daemon passes, as do guest_memrchr and the rest of the libc/libs scope. Merging once CI is green.