move env to a nix flake

dmenu/config.mk

@@ -5,20 +5,13 @@ VERSION = 5.4-odweta
 PREFIX = /usr
 MANPREFIX = $(PREFIX)/share/man
 
-X11INC = /usr/X11R6/include
-X11LIB = /usr/X11R6/lib
-
-# Xinerama, comment if you don't want it
-XINERAMALIBS  = -lXinerama
-XINERAMAFLAGS = -DXINERAMA
-
-# freetype
-FREETYPELIBS = -lfontconfig -lXft
-FREETYPEINC = /usr/include/freetype2
+# compiler and linker flags
+X11INC = $(shell $(PKG_CONFIG) --cflags x11 xft xrandr xinerama fontconfig freetype2)
+X11LIB = $(shell $(PKG_CONFIG) --libs x11 xft xrandr xinerama fontconfig freetype2)
 
 # includes and libs
-INCS = -I$(X11INC) -I$(FREETYPEINC)
-LIBS = -L$(X11LIB) -lX11 $(XINERAMALIBS) $(FREETYPELIBS)
+INCS = $(X11INC)
+LIBS = $(X11LIB)
 
 # flags
 CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700 -D_POSIX_C_SOURCE=200809L -DVERSION=\"$(VERSION)\" $(XINERAMAFLAGS)