AC_DEFUN(AC_SYS_LARGEFILE_TEST_INCLUDES,
[[ /* Check that off_t can represent 2**63 - 1 correctly.
We can't simply " since some C++ compilers masquerading as C compilers
incorrectly reject 9223372036854775807. */
int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
&& LARGE_OFF_T % 2147483647 == 1)
? 1 : -1];
]])
AC_DEFUN(AC_SYS_LARGEFILE_MACRO_VALUE,
[AC_CACHE_CHECK([for $1 value needed for large files], $3,
[$3=no
AC_TRY_COMPILE([$5],
[$6],
,
[AC_TRY_COMPILE([[$5]
,
[$6],
[$3=$2])])])
if test "[$]$3" != no; then
AC_DEFINE_UNQUOTED([$1], [$]$3, [$4])
fi])
AC_DEFUN(AC_SYS_LARGEFILE,
[AC_REQUIRE([AC_PROG_CC])
AC_ARG_ENABLE(largefile,
[ --disable-largefile omit support for large files])
if test "$enable_largefile" != no; then
AC_CACHE_CHECK([for special C compiler options needed for large files],
ac_cv_sys_largefile_CC,
[ac_cv_sys_largefile_CC=no
if test "$GCC" != yes; then
AC_TRY_COMPILE(AC_SYS_LARGEFILE_TEST_INCLUDES, , ,
[ac_save_CC="$CC"
CC="$CC -n32"
AC_TRY_COMPILE(AC_SYS_LARGEFILE_TEST_INCLUDES, ,
ac_cv_sys_largefile_CC=' -n32')
CC="$ac_save_CC"])
fi])
if test "$ac_cv_sys_largefile_CC" != no; then
CC="$CC$ac_cv_sys_largefile_CC"
fi
AC_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64,
ac_cv_sys_file_offset_bits,
[Number of bits in a file offset, on hosts where this is settable.],
AC_SYS_LARGEFILE_TEST_INCLUDES)
AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,
ac_cv_sys_large_files,
[Define for large files, on AIX-style hosts.],
AC_SYS_LARGEFILE_TEST_INCLUDES)
fi
])
AC_DEFUN(AC_FUNC_FSEEKO,
[AC_SYS_LARGEFILE_MACRO_VALUE(_LARGEFILE_SOURCE, 1,
ac_cv_sys_largefile_source,
[Define to make fseeko visible on some hosts (e.g. glibc 2.2).],
[
AC_CACHE_CHECK([for fseeko], ac_cv_func_fseeko,
[ac_cv_func_fseeko=no
AC_TRY_LINK([ [return fseeko && fseeko (stdin, 0, 0);],
[ac_cv_func_fseeko=yes])])
if test $ac_cv_func_fseeko != no; then
AC_DEFINE(HAVE_FSEEKO, 1,
[Define if fseeko (and presumably ftello) exists and is declared.])
fi])