Documenting syscalls does not mean a guarantee of stability. I can't recall any other Unixes except Linux which has committed to maintaining syscalls, which mea

Documenting syscalls does not mean a guarantee of stability. I can't recall any other Unixes except Linux which has committed to maintaining syscalls, which means this interface cannot be relied on. e.g. OpenBSD deletes "relic from the past" syscall: https://cvsweb.openbsd.org/src/sys/sys/syscall.h?rev=1.199&content-type=text/x-cvsweb-markup https://cvsweb.openbsd.org/src/sys/sys/syscall.h?rev=1.199&c... Solaris documenting deleted syscalls (note however the libc interface is guaruaneed): https://docs.oracle.com/cd/E23824_01/html/E22973/gkzlf.html https://docs.oracle.com/cd/E23824_01/html/E22973/gkzlf.html MacOS X is so unstable that even go developers had to go through libSystem: https://golang.org/doc/go1.12 https://golang.org/doc/go1.12