3
dnl By default, many hosts won't let programs access large files;
4
dnl one must use special compiler options to get large-file access to work.
5
dnl For more details about this brain damage please see:
6
dnl http://www.sas.com/standards/large.file/x_open.20Mar96.html
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dnl Written by Paul Eggert <eggert@twinsun.com>.
10
dnl Internal subroutine of AC_SYS_LARGEFILE.
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dnl AC_SYS_LARGEFILE_TEST_INCLUDES
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AC_DEFUN(AC_SYS_LARGEFILE_TEST_INCLUDES,
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[[#include <sys/types.h>
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int a[(off_t) 9223372036854775807 == 9223372036854775807 ? 1 : -1];
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dnl Internal subroutine of AC_SYS_LARGEFILE.
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dnl AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE, CACHE-VAR, COMMENT, INCLUDES, FUNCTION-BODY)
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AC_DEFUN(AC_SYS_LARGEFILE_MACRO_VALUE,
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[AC_CACHE_CHECK([for $1 value needed for large files], $3,
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AC_TRY_COMPILE(AC_SYS_LARGEFILE_TEST_INCLUDES
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[AC_TRY_COMPILE([#define $1 $2]
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AC_SYS_LARGEFILE_TEST_INCLUDES
33
if test "[$]$3" != no; then
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AC_DEFINE_UNQUOTED([$1], [$]$3, [$4])
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AC_DEFUN(AC_SYS_LARGEFILE,
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[AC_ARG_ENABLE(largefile,
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[ --disable-largefile omit support for large files])
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if test "$enable_largefile" != no; then
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AC_CACHE_CHECK([for special C compiler options needed for large files],
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ac_cv_sys_largefile_CC,
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[ac_cv_sys_largefile_CC=no
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if test "$GCC" != yes; then
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# IRIX 6.2 and later do not support large files by default,
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# so use the C compiler's -n32 option if that helps.
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AC_TRY_COMPILE(AC_SYS_LARGEFILE_TEST_INCLUDES, , ,
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AC_TRY_COMPILE(AC_SYS_LARGEFILE_TEST_INCLUDES, ,
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ac_cv_sys_largefile_CC=' -n32')
55
if test "$ac_cv_sys_largefile_CC" != no; then
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CC="$CC$ac_cv_sys_largefile_CC"
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AC_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64,
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ac_cv_sys_file_offset_bits,
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[Number of bits in a file offset, on hosts where this is settable.])
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AC_SYS_LARGEFILE_MACRO_VALUE(_LARGEFILE_SOURCE, 1,
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ac_cv_sys_largefile_source,
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[Define to make ftello visible on some hosts (e.g. HP-UX 10.20).],
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[#include <stdio.h>], [return !ftello;])
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AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,
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ac_cv_sys_large_files,
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[Define for large files, on AIX-style hosts.])
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AC_SYS_LARGEFILE_MACRO_VALUE(_XOPEN_SOURCE, 500,
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ac_cv_sys_xopen_source,
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[Define to make ftello visible on some hosts (e.g. glibc 2.1.3).],
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[#include <stdio.h>], [return !ftello;])