diff --git a/src/common/execio.h b/src/common/execio.h
--- a/src/common/execio.h
+++ b/src/common/execio.h
@@ -42,7 +42,7 @@ struct execio
 };
 
 /* nonzsero return on error */
-int execio_open(struct execio **rem, const char *progname, char *cont argv[]);
+int execio_open(struct execio **rem, const char *progname, char *const argv[]);
 
 /* 
    blocks,