[overlordxrz-source]

What

libkernel does not export system (Jc6E7N+dHz0). Yamagi Quake II (PPSA99007) stops on it at load on main, and ccleste (PPSA59322) imports it too.

In both titles the only caller is the bundled Mesa. A small function runs system("clrxdisasm --version > /dev/null 2>&1") and returns whether the result is 0, which tells Mesa whether the CLRX disassembler is installed. It sits on the shader-disassembly dump path, at 0x4608d0 in the PPSA99007 executable and 0x826270 in PPSA59322 (the single call [system] site in each).

system now follows FreeBSD 11's lib/libc/stdlib/system.c (source) for a process with no /bin/sh:

• A null command returns 1. That version returns 1 without checking for the shell (if (!command) return(1);).
• Any other command runs nothing and returns 0x7f00. In FreeBSD, the child that cannot execl(_PATH_BSHELL, ...) calls _exit(127), and system returns its wait status. So WIFEXITED is true and WEXITSTATUS is 127, and Mesa's probe sees that CLRX is not available.
• The guest errno is not touched.

No host command is ever run. A new line in docs/dev/TechnicalDebt.md says what is assumed: that the console's application sandbox has no shell, and that vfork succeeds there (FreeBSD returns -1 when it fails).

Log

I don't have a console, and I couldn't run the titles here: the host is aarch64 and the project needs x86-64. The stop is from @SleglJan's run of the homebrew catalog on main 4b6ab6b in #1578 (comment). Each title was relinked with --registry and run for 8 s on Linux. In the table of first stops, system is the stop for PPSA99007 Yamagi Quake II, with no open PR. That run reports the stop as app.elf: symbol lookup error: app.elf: undefined symbol: Jc6E7N+dHz0. Closed #3 also reported a Quake II build stopping at Jc6E7N+dHz0 (system) before guest entry.

• PPSA99007: ps5-yamagi-quake2 v0.2.0-alpha.1, PPSA99007.zip, sha256 4fa5da07…9a70, matching the catalog record
• PPSA59322: PS5_Celeste 1.00, PPSA59322.zip, sha256 96861b81…fb43. It stops earlier, on shm_open (separate PR).

The call sites come from the unwrapped eboot.bin of each release: the relocation for Jc6E7N+dHz0, then the only call qword ptr [rip+…] through that slot.

With this PR applied, @CouchRiv ran PPSA99007 on Linux (NVIDIA, main f145139 plus this PR, 90 s timeout) (comment). On main it stops at load with undefined symbol: Jc6E7N+dHz0, exit 127. With the PR, system resolves and the next stop is mkstemp (uEtgPWgPxOk, claimed by #1613):

/work/runtime/app.elf: symbol lookup error: /work/runtime/app.elf: undefined symbol: uEtgPWgPxOk

The LD_BIND_NOW trace goes from 21 to 20 unresolved imports, with nothing new.

Tested

aarch64 Debian 13 host. The full project cannot be built here because it needs x86-64.

• New core/libs/tests/GuestSystemCommand.cpp (guest_system_command) checks:
  • a null command returns 1
  • Mesa's probe string, exit 0 and an empty command each return a status with WIFEXITED true and exit status 127
  • errno is unchanged
• It passes natively on aarch64 (Zig 0.17 clang, glibc 2.36), and on x86_64-linux-musl under qemu-user. Both builds link the export's body with a guest errno stand-in.
• Negative check: without the change the test does not link. A mutant that returns 0 for a command aborts, and so does one that returns 0 for a null command.
• Process.cpp and the test compile for x86_64-linux-gnu and x86_64-windows-gnu with -Wall -Wextra. The only warnings are the existing -Wreturn-type-c-linkage ones from General.hpp and Shutdown.hpp.
• python3 tools/check_conventions.py --base origin/main passes. tools/progress.py: libkernel goes from 426 to 427 implemented.
• Title run by @CouchRiv: PPSA99007 on Linux/NVIDIA gets past system and stops next at mkstemp (feat(posix): implement mkstemp and isatty #1613). See Log.

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

[github-actions]

Progress report (ae91d97 → 8f09ec3)

➖ System libraries: 84.76% (+0.0%, +1 implemented functions)

✅ 1 implemented

Library	Name
libkernel	system_nid_postfix

[CouchRiv]

Ran Yamagi Quake II 0.2.0-alpha.1 (PPSA99007, homebrew catalog release) on Linux with this PR merged onto main f145139, in a sandbox, NVIDIA, 90 s timeout.

On main it stops at load, exit 127:

/work/runtime/app.elf: symbol lookup error: /work/runtime/app.elf: undefined symbol: Jc6E7N+dHz0

With this PR system resolves and the next stop is mkstemp (claimed by #1613), exit 127:

/work/runtime/app.elf: symbol lookup error: /work/runtime/app.elf: undefined symbol: uEtgPWgPxOk

The LD_BIND_NOW load trace goes from 21 to 20 unresolved imports, with nothing new.

[overlordxrz-source]

@CouchRiv thanks, that's the run this PR was missing. I've added it to Log and Tested. The next stop, mkstemp, belongs to #1613, so I'm leaving it out of this one.

[popcoder565]

First Windows run, since the description says it wasn't tested on Windows.

Setup: Windows 10 (19045), MinGW-w64 GCC 15.2.0 (WinLibs r7), Release. Merged onto main b7218b3 together with nine other small libc/libkernel PRs: #1975, #1976, #1977, #1685, #1676, #1675, #1641, #1656, #1807.

• guest_system_command passes.
• Full ctest: 510/510 (one GPU test skipped for a device limit).

🤖 Addressed by Claude Code

[adriadam10]

Checked the system semantics against FreeBSD 11 lib/libc/stdlib/system.c (null → 1, otherwise the wait status of a child that couldn't exec the shell, 127 << 8), the guest errno being left alone, the test registration in ctest and the TechnicalDebt entry. guest_system_command passes locally on Linux and fails to link without the change; Linux and Windows CI are green. Also confirmed by @CouchRiv (PPSA99007 on Linux/NVIDIA gets past system) and @popcoder565 (Windows, MinGW); merging.