X-Git-Url: https://git.cworth.org/git?p=tar;a=blobdiff_plain;f=m4%2Flink.m4;fp=m4%2Flink.m4;h=0ca85d3a8bed25fa4c2bf6133b1ba5dca59f7255;hp=0000000000000000000000000000000000000000;hb=de7372b23c3da92fbfaea2d1ac592f0b2ba87914;hpb=fbbfb9406a82e647ce27b6462b11a802fa48f31a

diff --git a/m4/link.m4 b/m4/link.m4
new file mode 100644
index 0000000..0ca85d3
--- /dev/null
+++ b/m4/link.m4
@@ -0,0 +1,38 @@
+# link.m4 serial 4
+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_LINK],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_CHECK_FUNCS_ONCE([link])
+  if test $ac_cv_func_link = no; then
+    HAVE_LINK=0
+    AC_LIBOBJ([link])
+  else
+    AC_CACHE_CHECK([whether link handles trailing slash correctly],
+      [gl_cv_func_link_works],
+      [touch conftest.a
+       # Assume that if we have lstat, we can also check symlinks.
+       if test $ac_cv_func_lstat = yes; then
+         ln -s conftest.a conftest.lnk
+       fi
+       AC_RUN_IFELSE(
+         [AC_LANG_PROGRAM(
+           [[#include <unistd.h>
+]], [[if (!link ("conftest.a", "conftest.b/")) return 1;
+#if HAVE_LSTAT
+      if (!link ("conftest.lnk/", "conftest.b")) return 2;
+#endif
+           ]])],
+         [gl_cv_func_link_works=yes], [gl_cv_func_link_works=no],
+         [gl_cv_func_link_works="guessing no"])
+       rm -f conftest.a conftest.b conftest.lnk])
+    if test "$gl_cv_func_link_works" != yes; then
+      REPLACE_LINK=1
+      AC_LIBOBJ([link])
+    fi
+  fi
+])