SEMSLEEP isn't defined in /sys/src/libc/9syscall/sys.h
; cd $home/nix-os
; grep SEMSLEEP `{find . }
./sys/src/nix/port/syscallfmt.c: case SEMSLEEP:
./sys/src/nix/port/systab.c: [SEMSLEEP] { "Semsleep", syssemsleep, { .i
= -1 } },- erik
