Sample extension module: InterSLIP control API.
diff --git a/Mac/Demo/interslip/InterslipLib.h b/Mac/Demo/interslip/InterslipLib.h
new file mode 100644
index 0000000..1ca2276
--- /dev/null
+++ b/Mac/Demo/interslip/InterslipLib.h
@@ -0,0 +1,20 @@
+/*
+** InterSLIP API.
+*/
+
+#include <Types.h>
+
+/* States */
+#define IS_IDLE 0
+#define IS_WMODEM 1
+#define IS_DIAL 2
+#define IS_LOGIN 3
+#define IS_RUN 4
+#define IS_DISC 5
+
+OSErr is_open(); /* Open InterSLIP driver (optional) */
+OSErr is_connect();/* Connect */
+OSErr is_disconnect(); /* Disconnect */
+OSErr is_status(long *, long *, StringPtr *); /* Get status, msg seq#, msg pointer */
+OSErr is_getconfig(long *, long *, Str255 , Str255 , Str255 ); /* get config */
+OSErr is_setconfig(long , long , Str255 , Str255 , Str255 ); /* set config */