vasnprintf: make use of _snprintf

[Bruno Haible]

vasnprintf.c uses HAVE_DECL__SNPRINTF, but it was not defined.
This was missing since 2003-11-16.


2007-06-10  Bruno Haible  <address@hidden>

        * m4/vasnprintf.m4 (gl_PREREQ_VASNPRINTF): Check for _snprintf
        declaration.

*** m4/vasnprintf.m4    6 Jun 2007 01:30:59 -0000       1.26
--- m4/vasnprintf.m4    10 Jun 2007 14:59:39 -0000
***************
*** 1,4 ****
! # vasnprintf.m4 serial 18
  dnl Copyright (C) 2002-2004, 2006-2007 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
--- 1,4 ----
! # vasnprintf.m4 serial 19
  dnl Copyright (C) 2002-2004, 2006-2007 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
***************
*** 57,62 ****
--- 57,65 ----
    AC_REQUIRE([gt_TYPE_WCHAR_T])
    AC_REQUIRE([gt_TYPE_WINT_T])
    AC_CHECK_FUNCS(snprintf wcslen)
+   dnl Use the _snprintf function only if it is declared (because on NetBSD it
+   dnl is defined as a weak alias of snprintf; we prefer to use the latter).
+   AC_CHECK_DECLS([_snprintf], , , [#include <stdio.h>])
  ])
  
  # Extra prerequisites of lib/vasnprintf.c for supporting 'long double'