diff --git a/Makefile b/Makefile
index caf9d48..28ca565 100644
--- a/Makefile
+++ b/Makefile
@@ -1,27 +1,17 @@
-# OS=$(uname) make 
-
-### OS = OpenBSD
-### OS = FreeBSD
 PROG=       xmem
 VERSION=    1.27
-FreeBSD_lflag=   -lkvm
-LDFLAGS+=   -L/usr/X11R6/lib -L/usr/local/lib/ -lX11 -lXt -lXaw -lXmu 
-LDFLAGS+=   $($(OS)_lflag)
+LDFLAGS+=   -L/usr/X11R6/lib -L/usr/local/lib/ -lX11 -lXt -lXaw -lXmu
+LDFLAGS+=   -lkvm
 CFLAGS+=    -Wall -I/usr/X11R6/include/ -I/usr/local/include/
-OBJECTS=    xmem.o  MemStripChart.o
-FreeBSD_stub =   get_mem_fbsd.o
-OpenBSD_stub =   get_mem.o
-_stub =   get_mem.o
-OBJECTS += $($(OS)_stub)
-
+OBJECTS=    xmem.o  MemStripChart.o get_mem.o
 
 all: xmem
 
 xmem.full:
-	echo "full not supported yet" 
+	@echo "full not supported yet"
 
 xmem.debug:
-	echo "debug not supported yet"
+	@echo "debug not supported yet"
 
 xmem: $(OBJECTS)
 	$(CC) -o xmem $(OBJECTS) $(LDFLAGS)
@@ -29,10 +19,10 @@ xmem: $(OBJECTS)
 %.o: %c
 	$(CC) $(CFLAGS) -c $<
 
-clean: 
+clean:
 	-rm -rf $(OBJECTS) $(PROG)
 
-dist: 
+dist:
 	mkdir -p ${PROG}-${VERSION}
 	cp *.h *.c Makefile xmem.1 xmem.bit copyright XMem.ad ${PROG}-${VERSION}
 	tar cfvz ${PROG}-${VERSION}.tar.gz ${PROG}-${VERSION}
@@ -48,9 +38,8 @@ install:
 	install -c -o root -g bin -m 644 xmem.1 ${PREFIX}/man/man1/xmem.1
 	install -d -m 755 ${PREFIX}/lib/X11/app-defaults/
 	install -c -o root -g bin -m 644 XMem.ad ${PREFIX}/lib/X11/app-defaults/XMem
-	install -d -m 755 ${PREFIX}/share/${PROG}/ 
+	install -d -m 755 ${PREFIX}/share/${PROG}/
 	install -c -o root -g bin -m 644 xmem.bit ${PREFIX}/share/${PROG}/xmem.bit
 	install -c -o root -g bin -m 644 copyright ${PREFIX}/share/${PROG}/copyright
 
-
 .include <bsd.prog.mk>
diff --git a/get_mem.c b/get_mem.c
index ed233fc..b2bcc9e 100644
--- a/get_mem.c
+++ b/get_mem.c
@@ -1,15 +1,17 @@
 /*  $Id: get_mem.c,v 1.5 2018/12/26 18:46:04 bch Exp $
- * 
- * Adapted: get memory usage on OpenBSD
- * Author: Christian Barthel <bch@online.de>
+ *
+ * xmem(1) utility adapted by Christian Barthel <bch@online.de>:
+ *   - Added OpenBSD support
+ *   - Added FreeBSD support
  *
  * get memory usage, from get_load.c derived
  *
  * Author:  Hans-Helmut Buehmann 20. Jan. 1996
- * 
+ *
  * Modified for more recent kernels Helmut Geyer Oct. 1996
  */
 
+#if __OpenBSD__
 
 #include <sys/param.h>	/* DEV_BSIZE MAXCOMLEN PZERO */
 #include <sys/sysctl.h>
@@ -26,11 +28,11 @@
 #include <err.h>
 #include "MemStripChart.h"
 
-static int pageshift = -1; 
+static int pageshift = -1;
 #define pagetok(size) ((size) << pageshift)
-#define LOG1024 10 
+#define LOG1024 10
 
-static double allmem_kb = 0; 
+static double allmem_kb = 0;
 
 static void initPageShift(void)
 {
@@ -43,7 +45,7 @@ static void initPageShift(void)
 	pageshift -= LOG1024;
 }
 
-static double getSwapFrac() 
+static double getSwapFrac()
 {
 	struct swapent *swdev;
 	int used, total, nswap, rnswap, i;
@@ -76,17 +78,17 @@ static double getSwapFrac()
 	return (double)used/total;
 }
 
-void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)	
+void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)
 {
 	static int bcstats_mib[] = {CTL_VFS, VFS_GENERIC, VFS_BCACHESTAT};
 	static int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
 	MemStripChartCallbackData ret;
 	struct uvmexp uvmexp;
 	struct bcachestats bcstats;
-	size_t size; 
-	
-	if (pageshift < 0) 
-		initPageShift(); 
+	size_t size;
+
+	if (pageshift < 0)
+		initPageShift();
 
 	size = sizeof(uvmexp);
 	if (sysctl(uvmexp_mib, 2, &uvmexp, &size, NULL, 0) < 0) {
@@ -100,7 +102,7 @@ void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)
 	}
 
 
-	allmem_kb = pagetok(uvmexp.npages); 
+	allmem_kb = pagetok(uvmexp.npages);
 	ret.cached = pagetok(bcstats.numbufpages) / allmem_kb;
 	ret.free = pagetok(uvmexp.free) / allmem_kb;
 	ret.buffer = 0;
@@ -108,9 +110,137 @@ void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)
 	ret.swap = getSwapFrac();
 
 #ifdef DEBUG
-	printf("%lf  %lf %lf  %lf %lf\n", allmem_kb, ret.code, ret.cached, ret.free, ret.swap);
+	printf("%lf  %lf %lf  %lf %lf\n",
+	    allmem_kb,
+	    ret.code,
+	    ret.cached,
+	    ret.free,
+	    ret.swap);
 #endif
-	
+
 	memcpy(call_data, &ret, sizeof(MemStripChartCallbackData));
 }
 
+#endif
+
+/* ------------------------------------------------------------------- */
+
+#if __FreeBSD__
+
+/*  $Id: get_mem_fbsd.c,v 1.1 2018/12/26 18:46:16 bch Exp $
+ *
+ * Author: Christian Barthel <bch@online.de>
+ */
+
+
+#include <sys/types.h>	/* DEV_BSIZE MAXCOMLEN PZERO */
+#include <sys/sysctl.h>
+
+#include <unistd.h>
+#include <kvm.h>
+
+#include <X11/Xos.h>
+#include <X11/Intrinsic.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <err.h>
+#include "MemStripChart.h"
+
+static int pageshift = -1;
+static int pagesize  = 0;
+static kvm_t *kd = 0;
+#define pagetok(size) ((size) << pageshift)
+#define LOG1024 10
+
+static unsigned int allmem_pages = 0;
+
+static void initPageShift(void)
+{
+	pagesize = getpagesize();
+	size_t len = sizeof(allmem_pages);
+	int mib[len];
+	pageshift = 0;
+	while (pagesize > 1) {
+		pageshift++;
+		pagesize >>= 1;
+	}
+	pageshift -= LOG1024;
+
+	kd = kvm_open(NULL, "/dev/null" ,NULL, O_RDONLY, "kvm_open");
+
+	if (sysctlbyname("vm.stats.vm.v_page_count", &allmem_pages, &len, NULL, 0) == -1)
+			perror("sysctl");
+#ifdef DEBUG
+	printf("page_count: %d\n", allmem_pages);
+#endif
+}
+
+static double getSwapFrac()
+{
+		/* XXX Borrowed from top(1) code: */
+		int n;
+		struct kvm_swap swapary[1];
+		static int pagesize = 0;
+		static unsigned long swap_maxpages = 0;
+		size_t sz = sizeof(swap_maxpages);
+
+		int retavail = 0;
+		int retfree = 0;
+
+
+		n = kvm_getswapinfo(kd, swapary, 1, 0);
+		if (n < 0 || swapary[0].ksw_total == 0)
+				return (0);
+
+		if (swap_maxpages == 0)
+				sysctlbyname("vm.swap_maxpages",
+					     &swap_maxpages, &sz, NULL, 0);
+
+		if ( swapary[0].ksw_total > swap_maxpages )
+				swapary[0].ksw_total = swap_maxpages;
+
+		retavail = swapary[0].ksw_total;
+		retfree = swapary[0].ksw_total - swapary[0].ksw_used;
+
+#ifdef DEBUG
+		printf("swap: %d %d %d %d\n", retavail,
+		       retavail, swapary[0].ksw_total,
+		       swapary[0].ksw_used);
+#endif
+		return (double)(retavail-retfree)/(double)retavail;
+}
+
+void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)
+{
+	MemStripChartCallbackData ret;
+	int a, b;
+	size_t sz = sizeof(int);
+	double cache = 0;
+
+	if (pageshift < 0)
+		initPageShift();
+
+	sysctlbyname("vm.stats.vm.v_wire_count", &a, &sz, NULL, 0);
+	ret.code = (double)a / (double)allmem_pages;
+
+	sysctlbyname("vm.stats.vm.v_active_count", &a, &sz, NULL, 0);
+	ret.buffer = (double)a / (double)allmem_pages;
+
+	/* v_cache_count and v_inactive_count are treated similarly */
+	sysctlbyname("vm.stats.vm.v_inactive_count", &a, &sz, NULL, 0);
+	sysctlbyname("vm.stats.vm.v_cache_count", &b, &sz, NULL, 0);
+	ret.cached = (double)(a + b) / allmem_pages;
+
+
+	sysctlbyname("vm.stats.vm.v_free_count", &a, &sz, NULL, 0);
+	ret.free = (double)a / allmem_pages;
+	ret.swap = getSwapFrac();
+
+#ifdef DEBUG
+	printf("%u  %lf %lf  %lf %lf\n", allmem_pages,
+				 ret.code, ret.cached, ret.free, ret.swap);
+#endif
+	memcpy(call_data, &ret, sizeof(MemStripChartCallbackData));
+}
+
+#endif
diff --git a/get_mem_fbsd.c b/get_mem_fbsd.c
deleted file mode 100644
index 2ba9cc0..0000000
--- a/get_mem_fbsd.c
+++ /dev/null
@@ -1,113 +0,0 @@
-/*  $Id: get_mem_fbsd.c,v 1.1 2018/12/26 18:46:16 bch Exp $
- * 
- * Author: Christian Barthel <bch@online.de>
- */
-
-
-#include <sys/types.h>	/* DEV_BSIZE MAXCOMLEN PZERO */
-#include <sys/sysctl.h>
-
-#include <unistd.h>
-#include <kvm.h>
-
-#include <X11/Xos.h>
-#include <X11/Intrinsic.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <err.h>
-#include "MemStripChart.h"
-
-static int pageshift = -1; 
-static int pagesize  = 0;
-static kvm_t *kd = 0;
-#define pagetok(size) ((size) << pageshift)
-#define LOG1024 10 
-
-static unsigned int allmem_pages = 0; 
-
-static void initPageShift(void)
-{
-	pagesize = getpagesize();
-	size_t len = sizeof(allmem_pages);
-	int mib[len];
-	pageshift = 0;
-	while (pagesize > 1) {
-		pageshift++;
-		pagesize >>= 1;
-	}
-	pageshift -= LOG1024;
-
-	kd = kvm_open(NULL, "/dev/null" ,NULL, O_RDONLY, "kvm_open");
-
-	if (sysctlbyname("vm.stats.vm.v_page_count", &allmem_pages, &len, NULL, 0) == -1)
-			perror("sysctl");
-#ifdef DEBUG
-	printf("page_count: %d\n", allmem_pages);
-#endif
-}
-
-static double getSwapFrac() 
-{
-		/* XXX Borrowed from top(1) code: */
-		int n;
-		struct kvm_swap swapary[1];
-		static int pagesize = 0;
-		static unsigned long swap_maxpages = 0;
-		size_t sz = sizeof(swap_maxpages);
-
-		int retavail = 0;
-		int retfree = 0;
-
-
-		n = kvm_getswapinfo(kd, swapary, 1, 0);
-		if (n < 0 || swapary[0].ksw_total == 0)
-				return (0);
-		
-		if (swap_maxpages == 0)
-				sysctlbyname("vm.swap_maxpages", &swap_maxpages, &sz, NULL, 0);
-
-		if ( swapary[0].ksw_total > swap_maxpages )
-				swapary[0].ksw_total = swap_maxpages;
-		
-		retavail = swapary[0].ksw_total;
-		retfree = swapary[0].ksw_total - swapary[0].ksw_used;
-
-#ifdef DEBUG
-		printf("swap: %d %d %d %d\n", retavail, retavail, swapary[0].ksw_total,
-					 swapary[0].ksw_used);
-#endif
-		return (double)(retavail-retfree)/(double)retavail;
-}
-
-void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)	
-{
-	MemStripChartCallbackData ret;
-	int a, b;
-	size_t sz = sizeof(int);
-	double cache = 0;
-	
-	if (pageshift < 0) 
-		initPageShift(); 
-
-	sysctlbyname("vm.stats.vm.v_wire_count", &a, &sz, NULL, 0);
-	ret.code = (double)a / (double)allmem_pages;
-
-	sysctlbyname("vm.stats.vm.v_active_count", &a, &sz, NULL, 0);
-	ret.buffer = (double)a / (double)allmem_pages;
-	
-	/* v_cache_count and v_inactive_count are treated similarly */
-	sysctlbyname("vm.stats.vm.v_inactive_count", &a, &sz, NULL, 0);
-	sysctlbyname("vm.stats.vm.v_cache_count", &b, &sz, NULL, 0);
-	ret.cached = (double)(a + b) / allmem_pages;
-
-
-	sysctlbyname("vm.stats.vm.v_free_count", &a, &sz, NULL, 0);
-	ret.free = (double)a / allmem_pages;
-	ret.swap = getSwapFrac();
-
-#ifdef DEBUG
-	printf("%u  %lf %lf  %lf %lf\n", allmem_pages, 
-				 ret.code, ret.cached, ret.free, ret.swap);
-#endif
-	memcpy(call_data, &ret, sizeof(MemStripChartCallbackData));
-}