1 files changed, 2 insertions, 2 deletions

diff --git a/st.c b/st.c
index 814f3f5..d8ff30b 100644
--- a/st.c
+++ b/st.c
@@ -2311,13 +2311,13 @@ techo(char *buf, int len) {
         for(; len > 0; buf++, len--) {
                 char c = *buf;
 
-                if(ISCONTROL(c)) { /* control code */
+                if(ISCONTROL((uchar) c)) { /* control code */
                         if(c & 0x80) {
                                 c &= 0x7f;
                                 tputc("^", 1);
                                 tputc("[", 1);
                         } else if(c != '\n' && c != '\r' && c != '\t') {
-                                c ^= '\x40';
+                                c ^= 0x40;
                                 tputc("^", 1);
                         }
                         tputc(&c, 1);