Fixed another instace of the Issue 173 (backported from master)

redis.c

@@ -7806,7 +7806,7 @@ static int syncRead(int fd, char *ptr, ssize_t size, int timeout) {
     while(size) {
         if (aeWait(fd,AE_READABLE,1000) & AE_READABLE) {
             nread = read(fd,ptr,size);
-            if (nread == -1) return -1;
+            if (nread <= 0) return -1;
             ptr += nread;
             size -= nread;
             totread += nread;