Also install include/Desktop/Mailer.h

Makefile

@@ -73,7 +73,7 @@ dist:
 		$(PACKAGE)-$(VERSION)/project.conf
 	$(RM) -- $(PACKAGE)-$(VERSION)
 
-install: all
+install:
 	@for i in $(SUBDIRS); do (cd $$i && $(MAKE) install) || exit; done
 
 uninstall:

include/Mailer.h

@@ -15,8 +15,8 @@
 
 
 
-#ifndef MAILER_MAILER_H
-# define MAILER_MAILER_H
+#ifndef DESKTOP_MAILER_H
+# define DESKTOP_MAILER_H
 
 # include <gtk/gtk.h>
 
@@ -123,4 +123,4 @@ enum
 # define MH_COL_LAST MH_COL_WEIGHT
 # define MH_COL_COUNT (MH_COL_LAST + 1)
 
-#endif /* !MAILER_MAILER_H */
+#endif /* !DESKTOP_MAILER_H */

include/Makefile

@@ -13,11 +13,11 @@ clean:
 
 distclean: clean
 
-install: all
-	$(MKDIR) $(DESTDIR)$(INCLUDEDIR)
-	$(INSTALL) -m 0644 -- Mailer.h $(DESTDIR)$(INCLUDEDIR)/Mailer.h
+install:
+	$(MKDIR) $(DESTDIR)$(PREFIX)/include/Desktop
+	$(INSTALL) -m 0644 -- Mailer.h $(DESTDIR)$(PREFIX)/include/Desktop/Mailer.h
 
 uninstall:
-	$(RM) -- $(DESTDIR)$(INCLUDEDIR)/Mailer.h
+	$(RM) -- $(DESTDIR)$(PREFIX)/include/Desktop/Mailer.h
 
 .PHONY: all clean distclean install uninstall

include/project.conf

@@ -1,2 +1,5 @@
 includes=Mailer.h
 dist=Makefile
+
+[Mailer.h]
+install=$(PREFIX)/include/Desktop