No need to use strlen() because the i variable counted the chars read

simulators/sim.h

@@ -107,12 +107,12 @@ getmyline(int fd, char *buf)
     {
         buf[i++] = c;
 
-        if (c == ';') { return strlen(buf); }
+        if (c == ';') { return i; }
     }
 
-    if (strlen(buf) == 0) { hl_usleep(10 * 1000); }
+    if (i == 0) { hl_usleep(10 * 1000); }
 
-    return strlen(buf);
+    return i;
 }
 
 int