1 files changed, 19 insertions, 0 deletions
diff --git a/config/auto-aux/bytecopy.c b/config/auto-aux/bytecopy.c
new file mode 100644
index 000000000..61fbb18d5
--- /dev/null
+++ b/config/auto-aux/bytecopy.c
@@ -0,0 +1,19 @@
+char buffer[27];
+
+#ifdef reverse
+#define cpy(s1,s2,n) copy(s2,s1,n)
+#else
+#define cpy copy
+#endif
+
+main()
+{
+  cpy("abcdefghijklmnopqrstuvwxyz", buffer, 27);
+  if (strcmp(buffer, "abcdefghijklmnopqrstuvwxyz") != 0) exit(1);
+  cpy(buffer, buffer+3, 26-3);
+  if (strcmp(buffer, "abcabcdefghijklmnopqrstuvw") != 0) exit(1);
+  cpy("abcdefghijklmnopqrstuvwxyz", buffer, 27);
+  cpy(buffer+3, buffer, 26-3);
+  if (strcmp(buffer, "defghijklmnopqrstuvwxyzxyz") != 0) exit(1);
+  exit(0);
+}