FreeBSD's kernel_sigaction rejects SIGKILL and SIGSTOP only for a handler other than SIG_DFL, so signal(9, SIG_DFL) and signal(17, SIG_DFL) succeed. Drop the SIG_ERR rejection, which has no kernel basis and which sigaction does not apply.
signal() returned SIG_ERR with EINVAL for any signal without a host
equivalent, such as SIGHUP, SIGPIPE and SIGUSR1, while sigaction()
accepted them. FreeBSD's signal() is sigaction() with SA_RESTART and fails
only for numbers outside 1..128 and for SIGKILL and SIGSTOP.
RetroArch (PPSA99169) stops at alarm on main: `FAIL: unresolved ELF import DQXJraCc1rA from libSceLibcInternal.prx`.
alarm(seconds) arms one process-wide real-time alarm and returns the seconds left on the previous one, rounded up like FreeBSD's alarm.c (any partial second counts); alarm(0) cancels it. When it expires, SIGALRM's disposition as recorded by sigaction or signal applies: ignored, nothing happens; default, the process terminates as on FreeBSD (exit status 128 + 14); a guest handler throws, because asynchronous delivery to a guest handler is not implemented.
The timer lives in libkernel next to the signal dispositions (GuestAlarm_nid_no_patch); libSceLibcInternal, which the titles import alarm from, forwards to it.
AI-assisted (Claude Code).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
sigprocmask keeps the first word of the title's set as it is, where
FreeBSD keeps signal n at bit n - 1 (_SIG_BIT), but Dispatch tested bit
n. A title that blocked SIGTERM with a FreeBSD-built set (bit 14) was
not protected, and a set with bit 15 blocked SIGTERM instead of SIGURG.
Dispatch now tests bit n - 1; the stored mask and the set returned by
sigprocmask are unchanged.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
EVO-PLAYER (PPSA99039) v0.11.0 stops at sigaction once its earlier
imports resolve: it installs a crash handler for SIGSEGV, SIGBUS and
SIGABRT and a quit handler for SIGTERM, SIGINT and SIGHUP at start-up.
sigaction records the handler, flags and mask of signals 1 to 128 and
reports them back, with FreeBSD's EINVAL cases. signal shares the table
and records SA_RESTART, as FreeBSD's libc does. Plain handlers on the
signals signal already delivers run as signal handlers do; SA_SIGINFO
handlers and other signals are recorded only, and raise of such a
signal throws.
Assisted by Claude Code.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DwFnKjMxmwGDWiuYYf1v4D
Guest signal handlers are called from a host dispatcher, so no guest PC is
a signal trampoline: return 0 for every address, as KytyPS5 and prosper do.
Co-Authored-By: Claude <noreply@anthropic.com>
Hussein Kadhim
Hannah Lyons
Scott Schuster
LeandroLP23
Jan Šlégl
john.maia
Adrià Franch
asimplestray
SamG-Coder