1 files changed, 2 insertions, 0 deletions

diff --git a/src/postprocess/sort_plz.c b/src/postprocess/sort_plz.c
index 4c30ea3..dc0b222 100644
--- a/src/postprocess/sort_plz.c
+++ b/src/postprocess/sort_plz.c
@@ -84,6 +84,8 @@ int main(int argc, char **args) {
   char *input = malloc(1024);
   size_t input_size = 1024;
 
+  if (argc != 1) exit(1);
+
   /* First open all input files */
   for (i=F_01; i<F_COUNT; ++i) {
     in_handles[i] = fopen_prefix(args[1], i, 1);