Move declarations to the appropriate header file

history.h

@@ -28,4 +28,12 @@ extern char *lastHist(Hist *hist);
 extern char *nextHist(Hist *hist);
 extern char *prevHist(Hist *hist);
 
+#ifdef USE_HISTORY
+extern int loadHistory(Hist *hist);
+extern void saveHistory(Hist *hist, size_t size);
+extern void ldHist(void);
+#else				/* not USE_HISTORY */
+#define ldHist nulcmd
+#endif				/* not USE_HISTORY */
+
 #endif				/* HISTORY_H */