--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toys/other/free.c	Sat Aug 25 14:25:22 2012 -0500
@@ -0,0 +1,60 @@
+/* vi: set sw=4 ts=4:
+ *
+ * free.c - Display amount of free and used memory in the system.
+ *
+ * Copyright 2012 Elie De Brauwer <eliedebrauwer@gmail.com>
+ *
+ * Not in SUSv4.
+
+USE_FREE(NEWTOY(free, "gmkb", TOYFLAG_USR|TOYFLAG_BIN))
+
+config FREE
+	bool "free"
+	default y
+	help
+	  usage: free [-bkmg]
+
+	  Display the total, free and used amount of physical memory and
+	  swap space.
+
+	  -bkmg    Output in bytes (default), KB, MB or GB
+*/
+
+#include "toys.h"
+
+static unsigned long long convert(unsigned long d, unsigned int iscale,
+				unsigned int oscale)
+{
+	return ((unsigned long long)d*iscale)>>oscale;
+}
+
+void free_main(void)
+{
+	struct sysinfo info;
+	unsigned int iscale = 1;
+	unsigned int oscale = 0;
+
+	sysinfo(&info);
+	if (info.mem_unit) iscale = info.mem_unit;
+	if (toys.optflags & 1) oscale = 0;
+	if (toys.optflags & 2) oscale = 10;
+	if (toys.optflags & 4) oscale = 20;
+	if (toys.optflags & 8) oscale = 30;
+
+	xprintf("\t\ttotal        used        free      shared     buffers\n");
+	xprintf("Mem:%17llu%12llu%12llu%12llu%12llu\n",
+		convert(info.totalram, iscale, oscale),
+		convert(info.totalram-info.freeram, iscale, oscale),
+		convert(info.freeram, iscale, oscale),
+		convert(info.sharedram, iscale, oscale),
+		convert(info.bufferram, iscale, oscale));
+
+	xprintf("-/+ buffers/cache:%15llu%12llu\n",
+		convert(info.totalram - info.freeram - info.bufferram, iscale, oscale),
+		convert(info.freeram + info.bufferram, iscale, oscale));
+
+	xprintf("Swap:%16llu%12llu%12llu\n",
+		convert(info.totalswap, iscale, oscale),
+		convert(info.totalswap - info.freeswap, iscale, oscale),
+		convert(info.freeswap, iscale, oscale));
+}