1 files changed, 1 insertions, 1 deletions
diff --git a/src/tftp.c b/src/tftp.c
index 0861f37..8e1dc4a 100644
--- a/src/tftp.c
+++ b/src/tftp.c
@@ -405,7 +405,7 @@ void tftp_request(struct listener *listen, time_t now)
 	if (*p == '\\')
 	  *p = '/';
 	else if (option_bool(OPT_TFTP_LC))
-	  *p = tolower(*p);
+	  *p = tolower((unsigned char)*p);
 		
       strcpy(daemon->namebuff, "/");
       if (prefix)