diff --git a/programs/pkey/gen_key.c b/programs/pkey/gen_key.c
index 7c8efef..2f3ba35 100644
--- a/programs/pkey/gen_key.c
+++ b/programs/pkey/gen_key.c
@@ -143,7 +143,7 @@
             return( ret );
 
         len = ret;
-        c = output_buf + sizeof(output_buf) - len - 1;
+        c = output_buf + sizeof(output_buf) - len;
     }
 
     if( ( f = fopen( output_file, "w" ) ) == NULL )