From 9e6fe01229e0ef4c0de5746f988f6a3c79b2f792 Mon Sep 17 00:00:00 2001
From: ceriel <none@none>
Date: Thu, 11 Dec 1986 17:04:40 +0000
Subject: [PATCH] Improved testing for 0-strings in the routine "mycat".

---
 mach/proto/ncg/compute.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mach/proto/ncg/compute.c b/mach/proto/ncg/compute.c
index c86e073d3..d023fd892 100644
--- a/mach/proto/ncg/compute.c
+++ b/mach/proto/ncg/compute.c
@@ -86,8 +86,8 @@ string salloc(),strcpy(),strcat();
 string mycat(s1,s2) register string s1,s2; {
 	register string s;
 
-	if (s1==0) return(s2);
-	if (s2==0) return(s1);
+	if (s1==0 || *s1=='\0') return(s2);
+	if (s2==0 || *s2=='\0') return(s1);
 	s=salloc(strlen(s1)+strlen(s2)+1);
 	strcpy(s,s1);
 	strcat(s,"+");
-- 
2.34.1