diff --git a/ldisc.h b/ldisc.h
new file mode 100644
index 00000000..aa904ed6
--- /dev/null
+++ b/ldisc.h
@@ -0,0 +1,21 @@
+/*
+ * ldisc.h: defines the Ldisc data structure used by ldisc.c and
+ * ldiscucs.c. (Unfortunately it was necessary to split the ldisc
+ * module in two, to avoid unnecessarily linking in the Unicode
+ * stuff in tools that don't require it.)
+ */
+
+#ifndef PUTTY_LDISC_H
+#define PUTTY_LDISC_H
+
+typedef struct ldisc_tag {
+    Terminal *term;
+    Backend *back;
+    void *backhandle;
+    void *frontend;
+
+    char *buf;
+    int buflen, bufsiz, quotenext;
+} *Ldisc;
+
+#endif /* PUTTY_LDISC_H */