+snippet/unused-parameter [test $REPLACE_FFLUSH = 1]
+fpurge [test $REPLACE_FFLUSH = 1]
+ftello [test $REPLACE_FFLUSH = 1]
+freading [test $REPLACE_FFLUSH = 1]
+lseek [test $REPLACE_FFLUSH = 1]
+unistd [test $REPLACE_FFLUSH = 1]
+fseeko [test $REPLACE_FFLUSH = 1]
+
+configure.ac-early:
+AC_REQUIRE([AC_FUNC_FSEEKO])