--- /dev/null
+/* cat.c
+
+ Copies one file to another, using mmap. */
+
+#include <stdio.h>
+#include <string.h>
+#include <syscall.h>
+
+int
+main (int argc, char *argv[])
+{
+ int in_fd, out_fd;
+ mapid_t in_map, out_map;
+ void *in_data = (void *) 0x10000000;
+ void *out_data = (void *) 0x20000000;
+ int size;
+
+ if (argc != 3)
+ {
+ printf ("usage: cp OLD NEW\n");
+ return 1;
+ }
+
+ /* Open input file. */
+ in_fd = open (argv[1]);
+ if (in_fd < 0)
+ {
+ printf ("%s: open failed\n", argv[1]);
+ return 1;
+ }
+ size = filesize (in_fd);
+
+ /* Create and open output file. */
+ if (!create (argv[2], size))
+ {
+ printf ("%s: create failed\n", argv[2]);
+ return 1;
+ }
+ out_fd = open (argv[2]);
+ if (out_fd < 0)
+ {
+ printf ("%s: open failed\n", argv[2]);
+ return 1;
+ }
+
+ /* Map files. */
+ in_map = mmap (in_fd, in_data);
+ if (in_map == MAP_FAILED)
+ {
+ printf ("%s: mmap failed\n", argv[1]);
+ return 1;
+ }
+ out_map = mmap (out_fd, out_data);
+ if (out_map == MAP_FAILED)
+ {
+ printf ("%s: mmap failed\n", argv[2]);
+ return 1;
+ }
+
+ /* Copy files. */
+ memcpy (out_data, in_data, size);
+
+ /* Unmap files (optional). */
+ munmap (in_map);
+ munmap (out_map);
+
+ return 0;
+}