-#serial 4
+# 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.
-dnl From J. David Anglin.
-
-dnl HPUX and other systems can't unlink shared text that is being executed.
-
-AC_DEFUN(jm_FUNC_UNLINK_BUSY_TEXT,
-[dnl
- AC_CACHE_CHECK([whether a program can unlink itself],
- jm_cv_func_unlink_busy_text,
- [
- AC_TRY_RUN([
- main (argc, argv)
- int argc;
- char **argv;
- {
- if (!argc)
- exit (-1);
- exit (unlink (argv[0]));
- }
- ],
- jm_cv_func_unlink_busy_text=yes,
- jm_cv_func_unlink_busy_text=no,
- jm_cv_func_unlink_busy_text=no
- )
- ]
- )
-
- if test $jm_cv_func_unlink_busy_text = no; then
- INSTALL=$ac_install_sh
+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
])