Imported Upstream version 1.4

[debian/gzip] / m4 / unlink.m4

diff --git a/m4/unlink.m4 b/m4/unlink.m4
new file mode 100644 (file)
index 0000000..c01d848
--- /dev/null
+++ b/m4/unlink.m4
@@ -0,0 +1,35 @@
+# unlink.m4 serial 3
+dnl Copyright (C) 2009, 2010 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_UNLINK],
+[
+  AC_REQUIRE([gl_AC_DOS])
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  dnl Detect Solaris 9 and FreeBSD 7.2 bug.
+  AC_CACHE_CHECK([whether unlink honors trailing slashes],
+    [gl_cv_func_unlink_works],
+    [touch conftest.file
+     # Assume that if we have lstat, we can also check symlinks.
+     if test $ac_cv_func_lstat = yes; then
+       ln -s conftest.file conftest.lnk
+     fi
+     AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+         [[#include <unistd.h>
+           #include <errno.h>
+]], [[if (!unlink ("conftest.file/") || errno != ENOTDIR) return 1;
+#if HAVE_LSTAT
+      if (!unlink ("conftest.lnk/") || errno != ENOTDIR) return 2;
+#endif
+      ]])],
+      [gl_cv_func_unlink_works=yes], [gl_cv_func_unlink_works=no],
+      [gl_cv_func_unlink_works="guessing no"])
+     rm -f conftest.file conftest.lnk])
+  if test x"$gl_cv_func_unlink_works" != xyes; then
+    REPLACE_UNLINK=1
+    AC_LIBOBJ([unlink])
+  fi
+])