origin_subst_one
static char *origin_subst_one(char *, const char *, const char *, bool);
res1 = origin_subst_one(real, "$ORIGIN", origin_path, false);
res2 = origin_subst_one(res1, "$OSNAME", uts.sysname, true);
res3 = origin_subst_one(res2, "$OSREL", uts.release, true);
res4 = origin_subst_one(res3, "$PLATFORM", uts.machine, true);