Update

src/examples/cp.c

+/* cat.c
+
+Copies one file to another. */
+
+#include <stdio.h>
+#include <syscall.h>
+
+int
+main (int argc, char *argv[])
+{
+  int in_fd, out_fd;
+
+  if (argc != 3)
+    {
+      printf ("usage: cp OLD NEW\n");
+      return EXIT_FAILURE;
+    }
+
+  /* Open input file. */
+  in_fd = open (argv[1]);
+  if (in_fd < 0)
+    {
+      printf ("%s: open failed\n", argv[1]);
+      return EXIT_FAILURE;
+    }
+
+  /* Create and open output file. */
+  if (!create (argv[2], filesize (in_fd)))
+    {
+      printf ("%s: create failed\n", argv[2]);
+      return EXIT_FAILURE;
+    }
+  out_fd = open (argv[2]);
+  if (out_fd < 0)
+    {
+      printf ("%s: open failed\n", argv[2]);
+      return EXIT_FAILURE;
+    }
+
+  /* Copy data. */
+  for (;;)
+    {
+      char buffer[1024];
+      int bytes_read = read (in_fd, buffer, sizeof buffer);
+      if (bytes_read == 0)
+        break;
+      if (write (out_fd, buffer, bytes_read) != bytes_read)
+        {
+          printf ("%s: write failed\n", argv[2]);
+          return EXIT_FAILURE;
+        }
+    }
+
+  return EXIT_SUCCESS;
+}