1 files changed, 25 insertions, 0 deletions
diff --git a/m4/dup.m4 b/m4/dup.m4
new file mode 100644
index 0000000..5105b6e
--- /dev/null
+++ b/m4/dup.m4
@@ -0,0 +1,25 @@
+# dup.m4 serial 3
+dnl Copyright (C) 2011-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_DUP],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_REQUIRE([gl_MSVC_INVAL])
+  if test $HAVE_MSVC_INVALID_PARAMETER_HANDLER = 1; then
+    REPLACE_DUP=1
+  fi
+  dnl Replace dup() for supporting the gnulib-defined fchdir() function,
+  dnl to keep fchdir's bookkeeping up-to-date.
+  m4_ifdef([gl_FUNC_FCHDIR], [
+    gl_TEST_FCHDIR
+    if test $HAVE_FCHDIR = 0; then
+      REPLACE_DUP=1
+    fi
+  ])
+])
+
+# Prerequisites of lib/dup.c.
+AC_DEFUN([gl_PREREQ_DUP], [:])