#define do_open(g, n, l, a, rm, rp, sf) \
do_openn(g, n, l, a, rm, rp, sf, (SV **) NULL, 0)
#ifdef PERL_DEFAULT_DO_EXEC3_IMPLEMENTATION
-#define do_exec(cmd) do_exec3(cmd,0,0)
+# define do_exec(cmd) do_exec3(cmd,0,0)
#endif
-#ifndef OS2
-#define do_aexec(really, mark,sp) do_aexec5(really, mark, sp, 0, 0)
+#ifdef OS2
+# define do_aexec Perl_do_aexec
+#else
+# define do_aexec(really, mark,sp) do_aexec5(really, mark, sp, 0, 0)
#endif
/* and finally... */