Change the default '\0' to ' ' when only-printable is used
diff --git a/fuzz.c b/fuzz.c
index a250e6d..6ac7bdc 100644
--- a/fuzz.c
+++ b/fuzz.c
@@ -173,7 +173,8 @@
      * dynamic corpus, so the dynamic phase doesn't fail because of lack of useful inputs
      */
     if (run->global->io.dynfileqCnt == 0) {
-        fuzz_addFileToFileQ(run->global, (const uint8_t*)"\0", 1U);
+        const char *single_byte = run->global->cfg.only_printable ? " " : "\0";
+        fuzz_addFileToFileQ(run->global, (const uint8_t*)single_byte, 1U);
     }
 }