master
remove -Werror from userland builds, to give us a chance to use more verbose warning options if desired. ok millert@, henning@, david@
drop useless .Li macros
When system calls indicate an error they return -1, not some arbitrary value < 0. errno is only updated in this case. Change all (most?) callers of syscalls to follow this better, and let's see if this strictness helps us in the future.