AC_HEADER_STDC # stdlib.h string.h (implied: errno.h limits.h stdio.h)
# Check for header files not covered by the predefined macros above.
-AC_CHECK_HEADERS([ fcntl.h getopt.h libgen.h limits.h linux/xattr.h ])
-AC_CHECK_HEADERS([ sys/acl.h sys/libacl.h unistd.h ])
+AC_CHECK_HEADERS([ acl/libacl.h fcntl.h getopt.h libgen.h limits.h ])
+AC_CHECK_HEADERS([ linux/xattr.h sys/acl.h unistd.h ])
# We need openat() with O_NOFOLLOW from POSIX-2008. Without them, we
# can't operate securely; I would rather refuse to be built.