in pathconf, -1, not 0, means unsupported.. syncio presumably works, too.
[musl] / src / signal / sigpending.c
1 #include <signal.h>
2 #include "syscall.h"
3
4 int sigpending(sigset_t *set)
5 {
6         return syscall(SYS_rt_sigpending, set, 8);
7 }