@@ -1970,11 +1970,11 @@
 	AC_SUBST(OF_SUBPROCESS_M, "OFSubprocess.m")
 	AC_DEFINE(OF_HAVE_SUBPROCESSES, 1, [Whether we have subprocesses])
 ])
 
 AC_CHECK_HEADERS_ONCE([complex.h sys/ioctl.h sys/ttycom.h])
-AC_CHECK_FUNCS(isatty)
+AC_CHECK_FUNCS(ioctl isatty)
 
 AC_CHECK_FUNC(pledge, [
 	AC_DEFINE(OF_HAVE_PLEDGE, 1, [Whether we have pledge()])
 ])