autoconf/acspecific.m4

# This file is part of Autoconf.                       -*- Autoconf -*-
# Macros that test for specific features.
# Copyright (C) 1992, 93, 94, 95, 96, 98, 99, 2000
# Free Software Foundation, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.
#
# As a special exception, the Free Software Foundation gives unlimited
# permission to copy, distribute and modify the configure scripts that
# are the output of Autoconf.  You need not follow the terms of the GNU
# General Public License when using or distributing such scripts, even
# though portions of the text of Autoconf appear in them.  The GNU
# General Public License (GPL) does govern all other use of the material
# that constitutes the Autoconf program.
#
# Certain portions of the Autoconf source text are designed to be copied
# (in certain cases, depending on the input) into the output of
# Autoconf.  We call these the "data" portions.  The rest of the Autoconf
# source text consists of comments plus executable code that decides which
# of the data portions to output in any given case.  We call these
# comments and executable code the "non-data" portions.  Autoconf never
# copies any of the non-data portions into its output.
#
# This special exception to the GPL applies to versions of Autoconf
# released by the Free Software Foundation.  When you make and
# distribute a modified version of Autoconf, you may extend this special
# exception to the GPL to apply to your modified version as well, *unless*
# your modified version has the potential to copy into its output some
# of the text that was the non-data portion of the version that you started
# with.  (In other words, unless your change moves or copies text from
# the non-data portions to the data portions.)  If your modification has
# such potential, you must delete any notice of this special exception
# to the GPL from your modified version.
#
# Written by David MacKenzie, with help from
# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
# Roland McGrath, Noah Friedman, david d zuhn, and many others.


## --------------------- ##
## Checks for programs.  ##
## --------------------- ##


# _AC_PROG_ECHO
# -------------
# Check whether to use -n, \c, or newline-tab to separate
# checking messages from result messages.
# Don't try to cache, since the results of this macro are needed to
# display the checking message.  In addition, caching something used once
# has little interest.
# Idea borrowed from dist 3.0.
AC_DEFUN([_AC_PROG_ECHO],
[if (echo "testing\c"; echo 1,2,3) | grep c >/dev/null; then
  # Stardent Vistra SVR4 grep lacks -e, says Kaveh R. Ghazi.
  if (echo -n testing; echo 1,2,3) | sed s/-n/xn/ | grep xn >/dev/null; then
    ECHO_N= ECHO_C='
' ECHO_T='	'
  else
    ECHO_N=-n ECHO_C= ECHO_T=
  fi
else
  ECHO_N= ECHO_C='\c' ECHO_T=
fi
AC_SUBST(ECHO_C)dnl
AC_SUBST(ECHO_N)dnl
AC_SUBST(ECHO_T)dnl
])# _AC_PROG_ECHO


# AC_PROG_MAKE_SET
# ----------------
# Define SET_MAKE to set ${MAKE} if make doesn't.
AC_DEFUN([AC_PROG_MAKE_SET],
[AC_MSG_CHECKING(whether ${MAKE-make} sets \${MAKE})
set dummy ${MAKE-make}; ac_make=`echo "$[2]" | sed 'y%./+-%__p_%'`
AC_CACHE_VAL(ac_cv_prog_make_${ac_make}_set,
[cat >conftestmake <<\EOF
all:
	@echo 'ac_maketemp="${MAKE}"'
EOF
# GNU make sometimes prints "make[1]: Entering...", which would confuse us.
eval `${MAKE-make} -f conftestmake 2>/dev/null | grep temp=`
if test -n "$ac_maketemp"; then
  eval ac_cv_prog_make_${ac_make}_set=yes
else
  eval ac_cv_prog_make_${ac_make}_set=no
fi
rm -f conftestmake])dnl
if eval "test \"`echo '$ac_cv_prog_make_'${ac_make}_set`\" = yes"; then
  AC_MSG_RESULT(yes)
  SET_MAKE=
else
  AC_MSG_RESULT(no)
  SET_MAKE="MAKE=${MAKE-make}"
fi
AC_SUBST([SET_MAKE])dnl
])# AC_PROG_MAKE_SET


AC_DEFUN([AC_PROG_RANLIB],
[AC_CHECK_PROG(RANLIB, ranlib, ranlib, :)])


# Check for mawk first since it's generally faster.
AC_DEFUN([AC_PROG_AWK],
[AC_CHECK_PROGS(AWK, mawk gawk nawk awk, )])


# AC_PROG_YACC
# ------------
AC_DEFUN([AC_PROG_YACC],
[AC_CHECK_PROGS(YACC, 'bison -y' byacc, yacc)])


# AC_PROG_LEX
# -----------
# Look for flex or lex.  Set its associated library to LEXLIB.
# Check if lex declares yytext as a char * by default, not a char[].
AC_DEFUN([AC_PROG_LEX],
[AH_CHECK_LIB(fl)dnl
AH_CHECK_LIB(l)dnl
AC_CHECK_PROG(LEX, flex, flex, lex)
if test -z "$LEXLIB"
then
  case $LEX in
  flex*) ac_lib=fl ;;
  *) ac_lib=l ;;
  esac
  AC_CHECK_LIB($ac_lib, yywrap, LEXLIB="-l$ac_lib")
fi
AC_SUBST(LEXLIB)
_AC_DECL_YYTEXT])


# _AC_DECL_YYTEXT
# ---------------
# Check if lex declares yytext as a char * by default, not a char[].
AC_DEFUN([_AC_DECL_YYTEXT],
[AC_REQUIRE_CPP()dnl
AC_CACHE_CHECK(lex output file root, ac_cv_prog_lex_root,
[# The minimal lex program is just a single line: %%.  But some broken lexes
# (Solaris, I think it was) want two %% lines, so accommodate them.
echo '%%
%%' | $LEX
if test -f lex.yy.c; then
  ac_cv_prog_lex_root=lex.yy
elif test -f lexyy.c; then
  ac_cv_prog_lex_root=lexyy
else
  AC_MSG_ERROR(cannot find output from $LEX; giving up)
fi])
LEX_OUTPUT_ROOT=$ac_cv_prog_lex_root
AC_SUBST(LEX_OUTPUT_ROOT)dnl

AC_CACHE_CHECK(whether yytext is a pointer, ac_cv_prog_lex_yytext_pointer,
[# POSIX says lex can declare yytext either as a pointer or an array; the
# default is implementation-dependent. Figure out which it is, since
# not all implementations provide the %pointer and %array declarations.
ac_cv_prog_lex_yytext_pointer=no
echo 'extern char *yytext;' >>$LEX_OUTPUT_ROOT.c
ac_save_LIBS=$LIBS
LIBS="$LIBS $LEXLIB"
AC_LINK_IFELSE([`cat $LEX_OUTPUT_ROOT.c`], ac_cv_prog_lex_yytext_pointer=yes)
LIBS=$ac_save_LIBS
rm -f "${LEX_OUTPUT_ROOT}.c"
])
dnl
if test $ac_cv_prog_lex_yytext_pointer = yes; then
  AC_DEFINE(YYTEXT_POINTER, 1,
            [Define if `lex' declares `yytext' as a `char *' by default,
             not a `char[]'.])
fi
])# _AC_DECL_YYTEXT


# Require AC_PROG_LEX in case some people were just calling this macro.
AU_DEFUN([AC_DECL_YYTEXT],
[AC_REQUIRE([AC_PROG_LEX])])


# AC_PROG_INSTALL
# ---------------
AC_DEFUN([AC_PROG_INSTALL],
[AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT])dnl
# Find a good install program.  We prefer a C program (faster),
# so one script is as good as another.  But avoid the broken or
# incompatible versions:
# SysV /etc/install, /usr/sbin/install
# SunOS /usr/etc/install
# IRIX /sbin/install
# AIX /bin/install
# AIX 4 /usr/bin/installbsd, which doesn't work without a -g flag
# AFS /usr/afsws/bin/install, which mishandles nonexistent args
# SVR4 /usr/ucb/install, which tries to use the nonexistent group "staff"
# ./install, which can be erroneously created by make from ./install.sh.
AC_MSG_CHECKING(for a BSD compatible install)
if test -z "$INSTALL"; then
AC_CACHE_VAL(ac_cv_path_install,
[  ac_save_IFS=$IFS; IFS=':'
  for ac_dir in $PATH; do
    # Account for people who put trailing slashes in PATH elements.
    case $ac_dir/ in
    /|./|.//|/etc/*|/usr/sbin/*|/usr/etc/*|/sbin/*|/usr/afsws/bin/*|/usr/ucb/*) ;;
    *)
      # OSF1 and SCO ODT 3.0 have their own names for install.
      # Don't use installbsd from OSF since it installs stuff as root
      # by default.
      for ac_prog in ginstall scoinst install; do
        if test -f $ac_dir/$ac_prog; then
	  if test $ac_prog = install &&
            grep dspmsg $ac_dir/$ac_prog >/dev/null 2>&1; then
	    # AIX install.  It has an incompatible calling convention.
	    :
	  elif test $ac_prog = install &&
	    grep pwplus $ac_dir/$ac_prog >/dev/null 2>&1; then
	    # program-specific install script used by HP pwplus--don't use.
	    :
	  else
	    ac_cv_path_install="$ac_dir/$ac_prog -c"
	    break 2
	  fi
	fi
      done
      ;;
    esac
  done
  IFS=$ac_save_IFS
])dnl
  if test "${ac_cv_path_install+set}" = set; then
    INSTALL=$ac_cv_path_install
  else
    # As a last resort, use the slow shell script.  We don't cache a
    # path for INSTALL within a source directory, because that will
    # break other packages using the cache if that directory is
    # removed, or if the path is relative.
    INSTALL=$ac_install_sh
  fi
fi
dnl We do special magic for INSTALL instead of AC_SUBST, to get
dnl relative paths right.
AC_MSG_RESULT($INSTALL)

# Use test -z because SunOS4 sh mishandles braces in ${var-val}.
# It thinks the first close brace ends the variable substitution.
test -z "$INSTALL_PROGRAM" && INSTALL_PROGRAM='${INSTALL}'
AC_SUBST(INSTALL_PROGRAM)dnl

test -z "$INSTALL_SCRIPT" && INSTALL_SCRIPT='${INSTALL}'
AC_SUBST(INSTALL_SCRIPT)dnl

test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
AC_SUBST(INSTALL_DATA)dnl
])# AC_PROG_INSTALL


# AC_PROG_LN_S
# ------------
AC_DEFUN([AC_PROG_LN_S],
[AC_MSG_CHECKING(whether ln -s works)
AC_CACHE_VAL(ac_cv_prog_LN_S,
[rm -f conftest.sym conftest.file
echo >conftest.file
if ln -s conftest.file conftest.sym 2>/dev/null; then
  ac_cv_prog_LN_S="ln -s"
else
  ac_cv_prog_LN_S=ln
fi])dnl
LN_S=$ac_cv_prog_LN_S
if test "$ac_cv_prog_LN_S" = "ln -s"; then
  AC_MSG_RESULT(yes)
else
  AC_MSG_RESULT(no)
fi
AC_SUBST(LN_S)dnl
])# AC_PROG_LN_S


AC_DEFUNCT([AC_RSH], [; replace it with equivalent code])




## ------------------------- ##
## Checks for declarations.  ##
## ------------------------- ##


# AC_DECL_SYS_SIGLIST
# -------------------
AC_DEFUN([AC_DECL_SYS_SIGLIST],
[AC_CACHE_CHECK([for sys_siglist declaration in signal.h or unistd.h],
  ac_cv_decl_sys_siglist,
[AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM([#include <sys/types.h>
#include <signal.h>
/* NetBSD declares sys_siglist in unistd.h.  */
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
], [char *msg = *(sys_siglist + 1);])],
                   [ac_cv_decl_sys_siglist=yes],
                   [ac_cv_decl_sys_siglist=no])])
if test $ac_cv_decl_sys_siglist = yes; then
  AC_DEFINE(SYS_SIGLIST_DECLARED, 1,
            [Define if `sys_siglist' is declared by <signal.h> or <unistd.h>.])
fi
])# AC_DECL_SYS_SIGLIST




## ------------------------- ##
## Checks for header files.  ##
## ------------------------- ##


# _AC_CHECK_HEADER_DIRENT(HEADER-FILE,
#                         [ACTION-IF-FOUND], [ACTION-IF-NOT_FOUND])
# -----------------------------------------------------------------
# Like AC_CHECK_HEADER, except also make sure that HEADER-FILE
# defines the type `DIR'.  dirent.h on NextStep 3.2 doesn't.
define([_AC_CHECK_HEADER_DIRENT],
[AC_VAR_PUSHDEF([ac_Header], [ac_cv_header_dirent_$1])dnl
AC_CACHE_CHECK([for $1 that defines DIR], ac_Header,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/types.h>
#include <$1>
],
                                    [DIR *dirp = 0;])],
                   [AC_VAR_SET(ac_Header, yes)],
                   [AC_VAR_SET(ac_Header, no)])])
AC_SHELL_IFELSE([test AC_VAR_GET(ac_Header) = yes],
                [$2], [$3])dnl
AC_VAR_POPDEF([ac_Header])dnl
])# _AC_CHECK_HEADER_DIRENT


# AH_CHECK_HEADERS_DIRENT(HEADERS...)
# -----------------------------------
define([AH_CHECK_HEADERS_DIRENT],
[AC_FOREACH([AC_Header], [$1],
  [AH_TEMPLATE(AC_TR_CPP(HAVE_[]AC_Header),
               [Define if you have the <]AC_Header[> header file, and
                it defines `DIR'.])])])


# AC_HEADER_DIRENT
# ----------------
AC_DEFUN([AC_HEADER_DIRENT],
[AH_CHECK_HEADERS_DIRENT(dirent.h sys/ndir.h sys/dir.h ndir.h)
ac_header_dirent=no
for ac_hdr in dirent.h sys/ndir.h sys/dir.h ndir.h; do
  _AC_CHECK_HEADER_DIRENT($ac_hdr,
                          [AC_DEFINE_UNQUOTED(AC_TR_CPP(HAVE_$ac_hdr), 1)
ac_header_dirent=$ac_hdr; break])
done
# Two versions of opendir et al. are in -ldir and -lx on SCO Xenix.
if test $ac_header_dirent = dirent.h; then
  AC_CHECK_LIB(dir, opendir, LIBS="$LIBS -ldir")
else
  AC_CHECK_LIB(x, opendir, LIBS="$LIBS -lx")
fi
])# AC_HEADER_DIRENT


# AC_HEADER_MAJOR
# ---------------
AC_DEFUN([AC_HEADER_MAJOR],
[AC_CACHE_CHECK(whether sys/types.h defines makedev,
  ac_cv_header_sys_types_h_makedev,
[AC_TRY_LINK([#include <sys/types.h>
], [return makedev(0, 0);],
  ac_cv_header_sys_types_h_makedev=yes, ac_cv_header_sys_types_h_makedev=no)
])

if test $ac_cv_header_sys_types_h_makedev = no; then
AC_CHECK_HEADER(sys/mkdev.h,
                [AC_DEFINE(MAJOR_IN_MKDEV, 1,
                           [Define if `major', `minor', and `makedev' are
                            declared in <mkdev.h>.])])

  if test $ac_cv_header_sys_mkdev_h = no; then
    AC_CHECK_HEADER(sys/sysmacros.h,
                    [AC_DEFINE(MAJOR_IN_SYSMACROS, 1,
                               [Define if `major', `minor', and `makedev' are
                                declared in <sysmacros.h>.])])
  fi
fi
])# AC_HEADER_MAJOR


# AC_HEADER_STAT
# --------------
# FIXME: Shouldn't this be named AC_HEADER_SYS_STAT?
AC_DEFUN([AC_HEADER_STAT],
[AC_CACHE_CHECK(whether stat file-mode macros are broken,
  ac_cv_header_stat_broken,
[AC_EGREP_CPP([You lose], [#include <sys/types.h>
#include <sys/stat.h>

#if defined(S_ISBLK) && defined(S_IFDIR)
# if S_ISBLK (S_IFDIR)
You lose.
# endif
#endif

#if defined(S_ISBLK) && defined(S_IFCHR)
# if S_ISBLK (S_IFCHR)
You lose.
# endif
#endif

#if defined(S_ISLNK) && defined(S_IFREG)
# if S_ISLNK (S_IFREG)
You lose.
# endif
#endif

#if defined(S_ISSOCK) && defined(S_IFREG)
# if S_ISSOCK (S_IFREG)
You lose.
# endif
#endif
], ac_cv_header_stat_broken=yes, ac_cv_header_stat_broken=no)])
if test $ac_cv_header_stat_broken = yes; then
  AC_DEFINE(STAT_MACROS_BROKEN, 1,
            [Define if the `S_IS*' macros in <sys/stat.h> do not
             work properly.])
fi
])# AC_HEADER_STAT


# AC_HEADER_STDC
# --------------
AC_DEFUN([AC_HEADER_STDC],
[AC_REQUIRE_CPP()dnl
AC_CACHE_CHECK(for ANSI C header files, ac_cv_header_stdc,
[AC_TRY_CPP([#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <float.h>
], ac_cv_header_stdc=yes, ac_cv_header_stdc=no)

if test $ac_cv_header_stdc = yes; then
  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
  AC_EGREP_HEADER(memchr, string.h, , ac_cv_header_stdc=no)
fi

if test $ac_cv_header_stdc = yes; then
  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
  AC_EGREP_HEADER(free, stdlib.h, , ac_cv_header_stdc=no)
fi

if test $ac_cv_header_stdc = yes; then
  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
  AC_TRY_RUN(
[#include <ctype.h>
#if ((' ' & 0x0FF) == 0x020)
# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
#else
# define ISLOWER(c) (('a' <= (c) && (c) <= 'i') \
                     || ('j' <= (c) && (c) <= 'r') \
                     || ('s' <= (c) && (c) <= 'z'))
# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
#endif

#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
int
main ()
{
  int i;
  for (i = 0; i < 256; i++)
    if (XOR (islower (i), ISLOWER (i))
        || toupper (i) != TOUPPER (i))
      exit(2);
  exit (0);
}], , ac_cv_header_stdc=no, :)
fi])
if test $ac_cv_header_stdc = yes; then
  AC_DEFINE(STDC_HEADERS, 1, [Define if you have the ANSI C header files.])
fi
])# AC_HEADER_STDC


# AC_HEADER_SYS_WAIT
# ------------------
AC_DEFUN([AC_HEADER_SYS_WAIT],
[AC_CACHE_CHECK([for sys/wait.h that is POSIX.1 compatible],
  ac_cv_header_sys_wait_h,
[AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM([#include <sys/types.h>
#include <sys/wait.h>
#ifndef WEXITSTATUS
# define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
#endif
#ifndef WIFEXITED
# define WIFEXITED(stat_val) (((stat_val) & 255) == 0)
#endif
],
[  int s;
  wait (&s);
  s = WIFEXITED (s) ? WEXITSTATUS (s) : 1;])],
                 [ac_cv_header_sys_wait_h=yes],
                 [ac_cv_header_sys_wait_h=no])])
if test $ac_cv_header_sys_wait_h = yes; then
  AC_DEFINE(HAVE_SYS_WAIT_H, 1,
            [Define if you have <sys/wait.h> that is POSIX.1 compatible.])
fi
])# AC_HEADER_SYS_WAIT


# AC_HEADER_TIME
# --------------
AC_DEFUN([AC_HEADER_TIME],
[AC_CACHE_CHECK([whether time.h and sys/time.h may both be included],
  ac_cv_header_time,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/types.h>
#include <sys/time.h>
#include <time.h>
],
[struct tm *tp;])],
                   [ac_cv_header_time=yes],
                   [ac_cv_header_time=no])])
if test $ac_cv_header_time = yes; then
  AC_DEFINE(TIME_WITH_SYS_TIME, 1,
            [Define if you can safely include both <sys/time.h> and <time.h>.])
fi
])# AC_HEADER_TIME




# A few hasbeen'd macros.

AC_DEFUNCT([AC_UNISTD_H], [; instead use AC_CHECK_HEADERS(unistd.h)])

AC_DEFUNCT([AC_USG],
           [; instead use AC_CHECK_HEADERS(string.h) and HAVE_STRING_H])

# If memchr and the like aren't declared in <string.h>, include <memory.h>.
# To avoid problems, don't check for gcc2 built-ins.
AC_DEFUNCT([AC_MEMORY_H],
           [; instead use AC_CHECK_HEADERS(memory.h) and HAVE_MEMORY_H])


# Like calling `AC_HEADER_DIRENT' and `AC_FUNC_CLOSEDIR_VOID', but
# defines a different set of C preprocessor macros to indicate which
# header file is found.  This macro and the names it defines are
# considered obsolete.
AC_DEFUNCT([AC_DIR_HEADER],
[; instead use AC_HEADER_DIRENT])






## --------------------- ##
## Checks for typedefs.  ##
## --------------------- ##


# AC_TYPE_GETGROUPS
# -----------------
AC_DEFUN([AC_TYPE_GETGROUPS],
[AC_REQUIRE([AC_TYPE_UID_T])dnl
AC_CACHE_CHECK(type of array argument to getgroups, ac_cv_type_getgroups,
[AC_TRY_RUN(
[/* Thanks to Mike Rendell for this test.  */
#include <sys/types.h>
#define NGID 256
#undef MAX
#define MAX(x, y) ((x) > (y) ? (x) : (y))
int
main ()
{
  gid_t gidset[NGID];
  int i, n;
  union { gid_t gval; long lval; }  val;

  val.lval = -1;
  for (i = 0; i < NGID; i++)
    gidset[i] = val.gval;
  n = getgroups (sizeof (gidset) / MAX (sizeof (int), sizeof (gid_t)) - 1,
                 gidset);
  /* Exit non-zero if getgroups seems to require an array of ints.  This
     happens when gid_t is short but getgroups modifies an array of ints.  */
  exit ((n > 0 && gidset[n] != val.gval) ? 1 : 0);
}],
  ac_cv_type_getgroups=gid_t, ac_cv_type_getgroups=int,
  ac_cv_type_getgroups=cross)
if test $ac_cv_type_getgroups = cross; then
  dnl When we can't run the test program (we are cross compiling), presume
  dnl that <unistd.h> has either an accurate prototype for getgroups or none.
  dnl Old systems without prototypes probably use int.
  AC_EGREP_HEADER([getgroups.*int.*gid_t], unistd.h,
		  ac_cv_type_getgroups=gid_t, ac_cv_type_getgroups=int)
fi])
AC_DEFINE_UNQUOTED(GETGROUPS_T, $ac_cv_type_getgroups,
                   [Define to the type of elements in the array set by
                    `getgroups'. Usually this is either `int' or `gid_t'.])
])# AC_TYPE_GETGROUPS


# AC_TYPE_UID_T
# -------------
# FIXME: Rewrite using AC_CHECK_TYPE.
AC_DEFUN([AC_TYPE_UID_T],
[AC_CACHE_CHECK(for uid_t in sys/types.h, ac_cv_type_uid_t,
[AC_EGREP_HEADER(uid_t, sys/types.h,
  ac_cv_type_uid_t=yes, ac_cv_type_uid_t=no)])
if test $ac_cv_type_uid_t = no; then
  AC_DEFINE(uid_t, int, [Define to `int' if <sys/types.h> doesn't define.])
  AC_DEFINE(gid_t, int, [Define to `int' if <sys/types.h> doesn't define.])
fi
])

# FIXME: AU_DEFUN these guys?
AC_DEFUN([AC_TYPE_SIZE_T],
[AC_CHECK_TYPE(size_t, unsigned)])

AC_DEFUN([AC_TYPE_PID_T],
[AC_CHECK_TYPE(pid_t, int)])

AC_DEFUN([AC_TYPE_OFF_T],
[AC_CHECK_TYPE(off_t, long)])

AC_DEFUN([AC_TYPE_MODE_T],
[AC_CHECK_TYPE(mode_t, int)])

AC_DEFUNCT([AC_INT_16_BITS], [; instead use AC_CHECK_SIZEOF(int)])
AC_DEFUNCT([AC_LONG_64_BITS], [; instead use AC_CHECK_SIZEOF(long)])


# AC_TYPE_SIGNAL
# --------------
# Note that identifiers starting with SIG are reserved by ANSI C.
AC_DEFUN([AC_TYPE_SIGNAL],
[AC_CACHE_CHECK([return type of signal handlers], ac_cv_type_signal,
[AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM([#include <sys/types.h>
#include <signal.h>
#ifdef signal
# undef signal
#endif
#ifdef __cplusplus
extern "C" void (*signal (int, void (*)(int)))(int);
#else
void (*signal ()) ();
#endif
],
                 [int i;])],
                   [ac_cv_type_signal=void],
                   [ac_cv_type_signal=int])])
AC_DEFINE_UNQUOTED(RETSIGTYPE, $ac_cv_type_signal,
                   [Define as the return type of signal handlers
                    (`int' or `void').])
])




## ---------------------- ##
## Checks for functions.  ##
## ---------------------- ##


# _AC_LIBOBJ_ALLOCA
# -----------------
# Set up the LIBOBJ replacement of `alloca'.  Well, not exactly
# AC_LIBOBJ since we actually set the output variable `ALLOCA'.
# Nevertheless, for Automake, AC_LIBOBJ_DECL it.
define([_AC_LIBOBJ_ALLOCA],
[# The SVR3 libPW and SVR4 libucb both contain incompatible functions
# that cause trouble.  Some versions do not even contain alloca or
# contain a buggy version.  If you still want to use their alloca,
# use ar to extract alloca.o from them instead of compiling alloca.c.
AC_LIBOBJ_DECL(alloca)
AC_SUBST(ALLOCA, alloca.${ac_objext})dnl
AC_DEFINE(C_ALLOCA, 1, [Define if using `alloca.c'.])

AC_CACHE_CHECK(whether `alloca.c' needs Cray hooks, ac_cv_os_cray,
[AC_EGREP_CPP(webecray,
[#if defined(CRAY) && ! defined(CRAY2)
webecray
#else
wenotbecray
#endif
], ac_cv_os_cray=yes, ac_cv_os_cray=no)])
if test $ac_cv_os_cray = yes; then
  for ac_func in _getb67 GETB67 getb67; do
    AC_CHECK_FUNC($ac_func,
  		  [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func,
  				      [Define to one of `_getb67', `GETB67',
  				       `getb67' for Cray-2 and Cray-YMP
                                       systems. This function is required for
                                       `alloca.c' support on those systems.])
    break])
  done
fi

AC_CACHE_CHECK(stack direction for C alloca, ac_cv_c_stack_direction,
[AC_TRY_RUN(
[int
find_stack_direction ()
{
  static char *addr = 0;
  auto char dummy;
  if (addr == 0)
    {
      addr = &dummy;
      return find_stack_direction ();
    }
  else
    return (&dummy > addr) ? 1 : -1;
}

int
main ()
{
  exit (find_stack_direction () < 0);
}], ac_cv_c_stack_direction=1, ac_cv_c_stack_direction=-1,
  ac_cv_c_stack_direction=0)])
AH_VERBATIM([STACK_DIRECTION],
[/* If using the C implementation of alloca, define if you know the
   direction of stack growth for your system; otherwise it will be
   automatically deduced at run-time.
        STACK_DIRECTION > 0 => grows toward higher addresses
        STACK_DIRECTION < 0 => grows toward lower addresses
        STACK_DIRECTION = 0 => direction of growth unknown */
@%:@undef STACK_DIRECTION])dnl
AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction)
])# _AC_LIBOBJ_ALLOCA


# AC_FUNC_ALLOCA
# --------------
AC_DEFUN([AC_FUNC_ALLOCA],
[AC_REQUIRE_CPP()dnl Set CPP; we run AC_EGREP_CPP conditionally.
# The Ultrix 4.2 mips builtin alloca declared by alloca.h only works
# for constant arguments.  Useless!
AC_CACHE_CHECK([for working alloca.h], ac_cv_working_alloca_h,
[AC_TRY_LINK([@%:@include <alloca.h>],
  [char *p = (char *) alloca (2 * sizeof (int));],
  ac_cv_working_alloca_h=yes, ac_cv_working_alloca_h=no)])
if test $ac_cv_working_alloca_h = yes; then
  AC_DEFINE(HAVE_ALLOCA_H, 1,
            [Define if you have <alloca.h> and it should be used
             (not on Ultrix).])
fi

AC_CACHE_CHECK([for alloca], ac_cv_func_alloca_works,
[AC_TRY_LINK(
[#ifdef __GNUC__
# define alloca __builtin_alloca
#else
# ifdef _MSC_VER
#  include <malloc.h>
#  define alloca _alloca
# else
#  if HAVE_ALLOCA_H
#   include <alloca.h>
#  else
#   ifdef _AIX
 #pragma alloca
#   else
#    ifndef alloca /* predefined by HP cc +Olibcalls */
char *alloca ();
#    endif
#   endif
#  endif
# endif
#endif
], [char *p = (char *) alloca (1);],
  ac_cv_func_alloca_works=yes, ac_cv_func_alloca_works=no)])

if test $ac_cv_func_alloca_works = yes; then
  AC_DEFINE(HAVE_ALLOCA, 1,
            [Define if you have `alloca', as a function or macro.])
else
  _AC_LIBOBJ_ALLOCA
fi
])# AC_FUNC_ALLOCA


# AC_FUNC_CHOWN
# -------------
# Determine whether chown accepts arguments of -1 for uid and gid.
AC_DEFUN([AC_FUNC_CHOWN],
[AC_REQUIRE([AC_TYPE_UID_T])dnl
AC_CHECK_HEADERS(unistd.h)
AC_CACHE_CHECK([for working chown], ac_cv_func_chown_works,
[AC_TRY_RUN([
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif

int
main ()
{
  char *f = "conftestchown";
  struct stat before, after;

  if (creat (f, 0600) < 0)
    exit (1);
  if (stat (f, &before) < 0)
    exit (1);
  if (chown (f, (uid_t) -1, (gid_t) -1) == -1)
    exit (1);
  if (stat (f, &after) < 0)
    exit (1);
  exit ((before.st_uid == after.st_uid
         && before.st_gid == after.st_gid) ? 0 : 1);
}],
            ac_cv_func_chown_works=yes,
            ac_cv_func_chown_works=no,
            ac_cv_func_chown_works=no)])
if test $ac_cv_func_chown_works = yes; then
  AC_DEFINE(HAVE_CHOWN, 1,
            [Define if your system has a working `chown' function.])
fi
])# AC_FUNC_CHOWN


# AC_FUNC_CLOSEDIR_VOID
# ---------------------
# Check whether closedir returns void, and #define CLOSEDIR_VOID in
# that case.
AC_DEFUN([AC_FUNC_CLOSEDIR_VOID],
[AC_REQUIRE([AC_HEADER_DIRENT])dnl
AC_CACHE_CHECK(whether closedir returns void, ac_cv_func_closedir_void,
[AC_TRY_RUN(
[#include <sys/types.h>
#include <$ac_header_dirent>

int closedir ();
int
main ()
{
  exit (closedir (opendir (".")) != 0);
}],
  ac_cv_func_closedir_void=no,
  ac_cv_func_closedir_void=yes,
  ac_cv_func_closedir_void=yes)])
if test $ac_cv_func_closedir_void = yes; then
  AC_DEFINE(CLOSEDIR_VOID, 1,
            [Define if the `closedir' function returns void instead of `int'.])
fi
])


# AC_FUNC_FNMATCH
# ---------------
# We look for fnmatch.h to avoid that the test fails in C++.
AC_DEFUN([AC_FUNC_FNMATCH],
[AC_CHECK_HEADERS(fnmatch.h)
AC_CACHE_CHECK(for working fnmatch, ac_cv_func_fnmatch_works,
# Some versions of Solaris or SCO have a broken fnmatch function.
# So we run a test program.  If we are cross-compiling, take no chance.
# Thanks to John Oleynick and Franc,ois Pinard for this test.
[AC_TRY_RUN(
[#if HAVE_FNMATCH_H
# include <fnmatch.h>
#endif

int
main ()
{
  exit (fnmatch ("a*", "abc", 0) != 0);
}],
ac_cv_func_fnmatch_works=yes, ac_cv_func_fnmatch_works=no,
ac_cv_func_fnmatch_works=no)])
if test $ac_cv_func_fnmatch_works = yes; then
  AC_DEFINE(HAVE_FNMATCH, 1,
            [Define if your system has a working `fnmatch' function.])
fi
])# AC_FUNC_FNMATCH


# AC_FUNC_GETGROUPS
# -----------------
# Try to find `getgroups', and check that it works.
# When crosscompiling, assume getgroups is broken.
AC_DEFUN([AC_FUNC_GETGROUPS],
[AC_REQUIRE([AC_TYPE_GETGROUPS])dnl
AC_REQUIRE([AC_TYPE_SIZE_T])dnl
AC_CHECK_FUNC(getgroups)

# If we don't yet have getgroups, see if it's in -lbsd.
# This is reported to be necessary on an ITOS 3000WS running SEIUX 3.1.
ac_save_LIBS=$LIBS
if test $ac_cv_func_getgroups = no; then
  AC_CHECK_LIB(bsd, getgroups, [GETGROUPS_LIB=-lbsd])
fi

# Run the program to test the functionality of the system-supplied
# getgroups function only if there is such a function.
if test $ac_cv_func_getgroups = yes; then
  AC_CACHE_CHECK([for working getgroups], ac_cv_func_getgroups_works,
   [AC_TRY_RUN([
     int
     main ()
     {
       /* On Ultrix 4.3, getgroups (0, 0) always fails.  */
       exit (getgroups (0, 0) == -1 ? 1 : 0);
     }],
               ac_cv_func_getgroups_works=yes,
               ac_cv_func_getgroups_works=no,
               ac_cv_func_getgroups_works=no)
   ])
  if test $ac_cv_func_getgroups_works = yes; then
    AC_DEFINE(HAVE_GETGROUPS, 1,
              [Define if your system has a working `getgroups' function.])
  fi
fi
LIBS=$ac_save_LIBS
])# AC_FUNC_GETGROUPS


# _AC_LIBOBJ_GETLOADAVG
# ---------------------
# Set up the AC_LIBOBJ replacement of `getloadavg'.
define([_AC_LIBOBJ_GETLOADAVG],
[AC_LIBOBJ(getloadavg)
AC_DEFINE(C_GETLOADAVG, 1, [Define if using `getloadavg.c'.])
# Figure out what our getloadavg.c needs.
ac_have_func=no
AC_CHECK_HEADER(sys/dg_sys_info.h,
[ac_have_func=yes
 AC_DEFINE(DGUX, 1, [Define for DGUX with <sys/dg_sys_info.h>.])
 AC_CHECK_LIB(dgc, dg_sys_info)])

AC_CHECK_HEADER(locale.h)
AC_CHECK_FUNCS(setlocale)

# We cannot check for <dwarf.h>, because Solaris 2 does not use dwarf (it
# uses stabs), but it is still SVR4.  We cannot check for <elf.h> because
# Irix 4.0.5F has the header but not the library.
if test $ac_have_func = no && test $ac_cv_lib_elf_elf_begin = yes; then
  ac_have_func=yes
  AC_DEFINE(SVR4, 1, [Define on System V Release 4.])
fi

if test $ac_have_func = no; then
  AC_CHECK_HEADER(inq_stats/cpustats.h,
  [ac_have_func=yes
   AC_DEFINE(UMAX, 1, [Define for Encore UMAX.])
   AC_DEFINE(UMAX4_3, 1,
             [Define for Encore UMAX 4.3 that has <inq_status/cpustats.h>
              instead of <sys/cpustats.h>.])])
fi

if test $ac_have_func = no; then
  AC_CHECK_HEADER(sys/cpustats.h,
  [ac_have_func=yes; AC_DEFINE(UMAX)])
fi

if test $ac_have_func = no; then
  AC_CHECK_HEADERS(mach/mach.h)
fi

AC_CHECK_HEADERS(nlist.h,
[AC_CHECK_MEMBERS([struct nlist.n_un.n_name],
                  [AC_DEFINE(NLIST_NAME_UNION, 1,
                             [Define if your `struct nlist' has an
                              `n_un' member.  Obsolete, depend on
                              `HAVE_STRUCT_NLIST_N_UN_N_NAME])], [],
                  [@%:@include <nlist.h>])
])dnl
])# _AC_LIBOBJ_GETLOADAVG


# AC_FUNC_GETLOADAVG
# ------------------
AC_DEFUN([AC_FUNC_GETLOADAVG],
[ac_have_func=no # yes means we've found a way to get the load average.

ac_save_LIBS=$LIBS

# Check for getloadavg, but be sure not to touch the cache variable.
(AC_CHECK_FUNC(getloadavg, exit 0, exit 1)) && ac_have_func=yes

# On HPUX9, an unprivileged user can get load averages through this function.
AC_CHECK_FUNCS(pstat_getdynamic)

# Solaris has libkstat which does not require root.
AC_CHECK_LIB(kstat, kstat_open)
test $ac_cv_lib_kstat_kstat_open = yes && ac_have_func=yes

# Some systems with -lutil have (and need) -lkvm as well, some do not.
# On Solaris, -lkvm requires nlist from -lelf, so check that first
# to get the right answer into the cache.
# For kstat on solaris, we need libelf to force the definition of SVR4 below.
if test $ac_have_func = no; then
  AC_CHECK_LIB(elf, elf_begin, LIBS="-lelf $LIBS")
fi
if test $ac_have_func = no; then
  AC_CHECK_LIB(kvm, kvm_open, LIBS="-lkvm $LIBS")
  # Check for the 4.4BSD definition of getloadavg.
  AC_CHECK_LIB(util, getloadavg,
    [LIBS="-lutil $LIBS" ac_have_func=yes ac_cv_func_getloadavg_setgid=yes])
fi

if test $ac_have_func = no; then
  # There is a commonly available library for RS/6000 AIX.
  # Since it is not a standard part of AIX, it might be installed locally.
  ac_getloadavg_LIBS=$LIBS
  LIBS="-L/usr/local/lib $LIBS"
  AC_CHECK_LIB(getloadavg, getloadavg,
               [LIBS="-lgetloadavg $LIBS"], [LIBS=$ac_getloadavg_LIBS])
fi

# Make sure it is really in the library, if we think we found it,
# otherwise set up the replacement function.
AC_CHECK_FUNCS(getloadavg, [],
               [_AC_LIBOBJ_GETLOADAVG])

# Some definitions of getloadavg require that the program be installed setgid.
dnl FIXME: Don't hardwire the path of getloadavg.c in the top-level directory.
AC_CACHE_CHECK(whether getloadavg requires setgid,
               ac_cv_func_getloadavg_setgid,
[AC_EGREP_CPP([Yowza Am I SETGID yet],
[#include "$srcdir/getloadavg.c"
#ifdef LDAV_PRIVILEGED
Yowza Am I SETGID yet
@%:@endif],
              ac_cv_func_getloadavg_setgid=yes,
              ac_cv_func_getloadavg_setgid=no)])
if test $ac_cv_func_getloadavg_setgid = yes; then
  NEED_SETGID=true
  AC_DEFINE(GETLOADAVG_PRIVILEGED, 1,
            [Define if the `getloadavg' function needs to be run setuid
             or setgid.])
else
  NEED_SETGID=false
fi
AC_SUBST(NEED_SETGID)dnl

if test $ac_cv_func_getloadavg_setgid = yes; then
  AC_CACHE_CHECK(group of /dev/kmem, ac_cv_group_kmem,
[ # On Solaris, /dev/kmem is a symlink.  Get info on the real file.
  ac_ls_output=`ls -lgL /dev/kmem 2>/dev/null`
  # If we got an error (system does not support symlinks), try without -L.
  test -z "$ac_ls_output" && ac_ls_output=`ls -lg /dev/kmem`
  ac_cv_group_kmem=`echo $ac_ls_output \
    | sed -ne ['s/[ 	][ 	]*/ /g;
	       s/^.[sSrwx-]* *[0-9]* *\([^0-9]*\)  *.*/\1/;
	       / /s/.* //;p;']`
])
  AC_SUBST(KMEM_GROUP, $ac_cv_group_kmem)dnl
fi
if test "x$ac_save_LIBS" = x; then
  GETLOADAVG_LIBS=$LIBS
else
  GETLOADAVG_LIBS=`echo "$LIBS" | sed "s!$ac_save_LIBS!!"`
fi
AC_SUBST(GETLOADAVG_LIBS)dnl
])# AC_FUNC_GETLOADAVG


# AC_FUNC_GETMNTENT
# -----------------
AC_DEFUN([AC_FUNC_GETMNTENT],
[# getmntent is in -lsun on Irix 4, -lseq on Dynix/PTX, -lgen on Unixware.
AC_CHECK_LIB(sun, getmntent, LIBS="-lsun $LIBS",
  [AC_CHECK_LIB(seq, getmntent, LIBS="-lseq $LIBS",
    [AC_CHECK_LIB(gen, getmntent, LIBS="-lgen $LIBS")])])
AC_CHECK_FUNC(getmntent,
              [AC_DEFINE(HAVE_GETMNTENT, 1,
                         [Define if you have the `getmntent' function.])])])


# AC_FUNC_GETPGRP
# ---------------
AC_DEFUN([AC_FUNC_GETPGRP],
[AC_CACHE_CHECK(whether getpgrp takes no argument, ac_cv_func_getpgrp_void,
[AC_TRY_RUN(
[/*
 * If this system has a BSD-style getpgrp(),
 * which takes a pid argument, exit unsuccessfully.
 *
 * Snarfed from Chet Ramey's bash pgrp.c test program
 */
#include <stdio.h>
#include <sys/types.h>

int     pid;
int     pg1, pg2, pg3, pg4;
int     ng, np, s, child;

int
main ()
{
  pid = getpid ();
  pg1 = getpgrp (0);
  pg2 = getpgrp ();
  pg3 = getpgrp (pid);
  pg4 = getpgrp (1);

  /* If all of these values are the same, it's pretty sure that we're
     on a system that ignores getpgrp's first argument.  */
  if (pg2 == pg4 && pg1 == pg3 && pg2 == pg3)
    exit (0);

  child = fork ();
  if (child < 0)
    exit(1);
  else if (child == 0)
    {
      np = getpid ();
      /*  If this is Sys V, this will not work; pgrp will be set to np
	 because setpgrp just changes a pgrp to be the same as the
	 pid.  */
      setpgrp (np, pg1);
      ng = getpgrp (0);        /* Same result for Sys V and BSD */
      if (ng == pg1)
  	exit (1);
      else
  	exit (0);
    }
  else
    {
      wait (&s);
      exit (s>>8);
    }
}], ac_cv_func_getpgrp_void=yes, ac_cv_func_getpgrp_void=no,
   AC_MSG_ERROR(cannot check getpgrp if cross compiling))
])
if test $ac_cv_func_getpgrp_void = yes; then
  AC_DEFINE(GETPGRP_VOID, 1,
            [Define if the `getpgrp' function takes no argument.])
fi
])# AC_FUNC_GETPGRP


# AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK
# -------------------------------------
# When crosscompiling, be pessimistic so we will end up using the
# replacement version of lstat that checkes for trailing slashes and
# calls lstat a second time when necessary.
AC_DEFUN([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK],
[AC_CACHE_CHECK(
       [whether lstat dereferences a symlink specified with a trailing slash],
       [ac_cv_func_lstat_dereferences_slashed_symlink],
[rm -f conftest.sym conftest.file
echo >conftest.file
if ln -s conftest.file conftest.sym; then
  AC_TRY_RUN([
#  include <sys/types.h>
#  include <sys/stat.h>

   int
   main ()
   {
     struct stat sbuf;
     /* Linux will dereference the symlink and fail.
        That is better in the sense that it means we will not
        have to compile and use the lstat wrapper.  */
     exit (lstat ("conftest.sym/", &sbuf) ? 0 : 1);
   }
   ],
   ac_cv_func_lstat_dereferences_slashed_symlink=yes,
   ac_cv_func_lstat_dereferences_slashed_symlink=no,
   ac_cv_func_lstat_dereferences_slashed_symlink=no
  )
else
  # If the `ln -s' command failed, then we probably don't even
  # have an lstat function.
  ac_cv_func_lstat_dereferences_slashed_symlink=no
fi
])

test $ac_cv_func_lstat_dereferences_slashed_symlink = yes &&
  AC_DEFINE_UNQUOTED(LSTAT_FOLLOWS_SLASHED_SYMLINK, 1,
                     [Define if `lstat' dereferences a symlink specified
                      with a trailing slash.])

if test $ac_cv_func_lstat_dereferences_slashed_symlink = no; then
  AC_LIBOBJ(lstat)
fi
])


# AC_FUNC_MALLOC
# --------------
# Is `malloc (0)' properly handled?
AC_DEFUN([AC_FUNC_MALLOC],
[AC_REQUIRE([AC_HEADER_STDC])dnl
AC_CACHE_CHECK([for working malloc], ac_cv_func_malloc_works,
[AC_TRY_RUN(
[#if STDC_HEADERS || HAVE_STDLIB_H
# include <stdlib.h>
#else
char *malloc ();
#endif

int
main ()
{
  exit (malloc (0) ? 0 : 1);
}],
              ac_cv_func_malloc_works=yes,
              ac_cv_func_malloc_works=no,
              ac_cv_func_malloc_works=no)
  ])
if test $ac_cv_func_malloc_works = yes; then
  AC_DEFINE(HAVE_MALLOC, 1,
            [Define if your system has a working `malloc' function.])
fi
])# AC_FUNC_MALLOC


# AC_FUNC_MEMCMP
# --------------
AC_DEFUN([AC_FUNC_MEMCMP],
[AC_CACHE_CHECK([for working memcmp], ac_cv_func_memcmp_working,
[AC_TRY_RUN([
int
main ()
{
  /* Some versions of memcmp are not 8-bit clean.  */
  char c0 = 0x40, c1 = 0x80, c2 = 0x81;
  if (memcmp(&c0, &c2, 1) >= 0 || memcmp(&c1, &c2, 1) >= 0)
    exit (1);

  /* The Next x86 OpenStep bug shows up only when comparing 16 bytes
     or more and with at least one buffer not starting on a 4-byte boundary.
     William Lewis provided this test program.   */
  {
    char foo[21];
    char bar[21];
    int i;
    for (i = 0; i < 4; i++)
      {
        char *a = foo + i;
        char *b = bar + i;
        strcpy (a, "--------01111111");
        strcpy (b, "--------10000000");
        if (memcmp (a, b, 16) >= 0)
          exit (1);
      }
    exit (0);
  }
}]
   ac_cv_func_memcmp_working=yes,
   ac_cv_func_memcmp_working=no,
   ac_cv_func_memcmp_working=no)])
test $ac_cv_func_memcmp_working = no && AC_LIBOBJ([memcmp])
])# AC_FUNC_MEMCMP


# AC_FUNC_MKTIME
# --------------
AC_DEFUN([AC_FUNC_MKTIME],
[AC_REQUIRE([AC_HEADER_TIME])dnl
AC_CHECK_HEADERS(sys/time.h unistd.h)
AC_CHECK_FUNCS(alarm)
AC_CACHE_CHECK([for working mktime], ac_cv_func_working_mktime,
[AC_TRY_RUN(
[/* Test program from Paul Eggert and Tony Leneis.  */
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
#  include <sys/time.h>
# else
#  include <time.h>
# endif
#endif

#if HAVE_UNISTD_H
# include <unistd.h>
#endif

#if !HAVE_ALARM
# define alarm(X) /* empty */
#endif

/* Work around redefinition to rpl_putenv by other config tests.  */
#undef putenv

static time_t time_t_max;

/* Values we'll use to set the TZ environment variable.  */
static const char *const tz_strings[] = {
  (const char *) 0, "TZ=GMT0", "TZ=JST-9",
  "TZ=EST+3EDT+2,M10.1.0/00:00:00,M2.3.0/00:00:00"
};
#define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))

/* Fail if mktime fails to convert a date in the spring-forward gap.
   Based on a problem report from Andreas Jaeger.  */
static void
spring_forward_gap ()
{
  /* glibc (up to about 1998-10-07) failed this test) */
  struct tm tm;

  /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
     instead of "TZ=America/Vancouver" in order to detect the bug even
     on systems that don't support the Olson extension, or don't have the
     full zoneinfo tables installed.  */
  putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");

  tm.tm_year = 98;
  tm.tm_mon = 3;
  tm.tm_mday = 5;
  tm.tm_hour = 2;
  tm.tm_min = 0;
  tm.tm_sec = 0;
  tm.tm_isdst = -1;
  if (mktime (&tm) == (time_t)-1)
    exit (1);
}

static void
mktime_test (now)
     time_t now;
{
  struct tm *lt;
  if ((lt = localtime (&now)) && mktime (lt) != now)
    exit (1);
  now = time_t_max - now;
  if ((lt = localtime (&now)) && mktime (lt) != now)
    exit (1);
}

static void
irix_6_4_bug ()
{
  /* Based on code from Ariel Faigon.  */
  struct tm tm;
  tm.tm_year = 96;
  tm.tm_mon = 3;
  tm.tm_mday = 0;
  tm.tm_hour = 0;
  tm.tm_min = 0;
  tm.tm_sec = 0;
  tm.tm_isdst = -1;
  mktime (&tm);
  if (tm.tm_mon != 2 || tm.tm_mday != 31)
    exit (1);
}

static void
bigtime_test (j)
     int j;
{
  struct tm tm;
  time_t now;
  tm.tm_year = tm.tm_mon = tm.tm_mday = tm.tm_hour = tm.tm_min = tm.tm_sec = j;
  now = mktime (&tm);
  if (now != (time_t) -1)
    {
      struct tm *lt = localtime (&now);
      if (! (lt
	     && lt->tm_year == tm.tm_year
	     && lt->tm_mon == tm.tm_mon
	     && lt->tm_mday == tm.tm_mday
	     && lt->tm_hour == tm.tm_hour
	     && lt->tm_min == tm.tm_min
	     && lt->tm_sec == tm.tm_sec
	     && lt->tm_yday == tm.tm_yday
	     && lt->tm_wday == tm.tm_wday
	     && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
		  == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
	exit (1);
    }
}

int
main ()
{
  time_t t, delta;
  int i, j;

  /* This test makes some buggy mktime implementations loop.
     Give up after 60 seconds; a mktime slower than that
     isn't worth using anyway.  */
  alarm (60);

  for (time_t_max = 1; 0 < time_t_max; time_t_max *= 2)
    continue;
  time_t_max--;
  delta = time_t_max / 997; /* a suitable prime number */
  for (i = 0; i < N_STRINGS; i++)
    {
      if (tz_strings[i])
	putenv (tz_strings[i]);

      for (t = 0; t <= time_t_max - delta; t += delta)
	mktime_test (t);
      mktime_test ((time_t) 60 * 60);
      mktime_test ((time_t) 60 * 60 * 24);

      for (j = 1; 0 < j; j *= 2)
        bigtime_test (j);
      bigtime_test (j - 1);
    }
  irix_6_4_bug ();
  spring_forward_gap ();
  exit (0);
}],
ac_cv_func_working_mktime=yes, ac_cv_func_working_mktime=no,
ac_cv_func_working_mktime=no)])
if test $ac_cv_func_working_mktime = no; then
  AC_LIBOBJ([mktime])
fi
])# AC_FUNC_MKTIME


# AC_FUNC_MMAP
# ------------
AC_DEFUN([AC_FUNC_MMAP],
[AC_CHECK_HEADERS(stdlib.h unistd.h sys/stat.h)
AC_CHECK_FUNCS(getpagesize)
AC_CACHE_CHECK(for working mmap, ac_cv_func_mmap_fixed_mapped,
[AC_TRY_RUN(
[/* Thanks to Mike Haertel and Jim Avera for this test.
   Here is a matrix of mmap possibilities:
	mmap private not fixed
	mmap private fixed at somewhere currently unmapped
	mmap private fixed at somewhere already mapped
	mmap shared not fixed
	mmap shared fixed at somewhere currently unmapped
	mmap shared fixed at somewhere already mapped
   For private mappings, we should verify that changes cannot be read()
   back from the file, nor mmap's back from the file at a different
   address.  (There have been systems where private was not correctly
   implemented like the infamous i386 svr4.0, and systems where the
   VM page cache was not coherent with the file system buffer cache
   like early versions of FreeBSD and possibly contemporary NetBSD.)
   For shared mappings, we should conversely verify that changes get
   propogated back to all the places they're supposed to be.

   Grep wants private fixed already mapped.
   The main things grep needs to know about mmap are:
   * does it exist and is it safe to write into the mmap'd area
   * how to use it (BSD variants)  */
#include <sys/types.h>
#include <fcntl.h>
#include <sys/mman.h>

#if STDC_HEADERS || HAVE_STDLIB_H
# include <stdlib.h>
#else
char *malloc ();
#endif
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#if HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif

/* This mess was copied from the GNU getpagesize.h.  */
#if !HAVE_GETPAGESIZE
/* Assume that all systems that can run configure have sys/param.h.  */
# if !HAVE_SYS_PARAM_H
#  define HAVE_SYS_PARAM_H 1
# endif

# ifdef _SC_PAGESIZE
#  define getpagesize() sysconf(_SC_PAGESIZE)
# else /* no _SC_PAGESIZE */
#  if HAVE_SYS_PARAM_H
#   include <sys/param.h>
#   ifdef EXEC_PAGESIZE
#    define getpagesize() EXEC_PAGESIZE
#   else /* no EXEC_PAGESIZE */
#    ifdef NBPG
#     define getpagesize() NBPG * CLSIZE
#     ifndef CLSIZE
#      define CLSIZE 1
#     endif /* no CLSIZE */
#    else /* no NBPG */
#     ifdef NBPC
#      define getpagesize() NBPC
#     else /* no NBPC */
#      ifdef PAGESIZE
#       define getpagesize() PAGESIZE
#      endif /* PAGESIZE */
#     endif /* no NBPC */
#    endif /* no NBPG */
#   endif /* no EXEC_PAGESIZE */
#  else /* no HAVE_SYS_PARAM_H */
#   define getpagesize() 8192	/* punt totally */
#  endif /* no HAVE_SYS_PARAM_H */
# endif /* no _SC_PAGESIZE */

#endif /* no HAVE_GETPAGESIZE */

int
main ()
{
  char *data, *data2, *data3;
  int i, pagesize;
  int fd;

  pagesize = getpagesize ();

  /* First, make a file with some known garbage in it. */
  data = (char *) malloc (pagesize);
  if (!data)
    exit (1);
  for (i = 0; i < pagesize; ++i)
    *(data + i) = rand ();
  umask (0);
  fd = creat ("conftestmmap", 0600);
  if (fd < 0)
    exit (1);
  if (write (fd, data, pagesize) != pagesize)
    exit (1);
  close (fd);

  /* Next, try to mmap the file at a fixed address which already has
     something else allocated at it.  If we can, also make sure that
     we see the same garbage.  */
  fd = open ("conftestmmap", O_RDWR);
  if (fd < 0)
    exit (1);
  data2 = (char *) malloc (2 * pagesize);
  if (!data2)
    exit (1);
  data2 += (pagesize - ((int) data2 & (pagesize - 1))) & (pagesize - 1);
  if (data2 != mmap (data2, pagesize, PROT_READ | PROT_WRITE,
                     MAP_PRIVATE | MAP_FIXED, fd, 0L))
    exit (1);
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data2 + i))
      exit (1);

  /* Finally, make sure that changes to the mapped area do not
     percolate back to the file as seen by read().  (This is a bug on
     some variants of i386 svr4.0.)  */
  for (i = 0; i < pagesize; ++i)
    *(data2 + i) = *(data2 + i) + 1;
  data3 = (char *) malloc (pagesize);
  if (!data3)
    exit (1);
  if (read (fd, data3, pagesize) != pagesize)
    exit (1);
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data3 + i))
      exit (1);
  close (fd);
  unlink ("conftestmmap");
  exit (0);
}], ac_cv_func_mmap_fixed_mapped=yes, ac_cv_func_mmap_fixed_mapped=no,
ac_cv_func_mmap_fixed_mapped=no)])
if test $ac_cv_func_mmap_fixed_mapped = yes; then
  AC_DEFINE(HAVE_MMAP, 1,
            [Define if you have a working `mmap' system call.])
fi
])# AC_FUNC_MMAP


# AC_FUNC_SELECT_ARGTYPES
# -----------------------
# Determine the correct type to be passed to each of the `select'
# function's arguments, and define those types in `SELECT_TYPE_ARG1',
# `SELECT_TYPE_ARG234', and `SELECT_TYPE_ARG5'.
AC_DEFUN([AC_FUNC_SELECT_ARGTYPES],
[AC_CACHE_CHECK([types of arguments for select],
[ac_cv_func_select_args],
[for ac_arg234 in 'fd_set *' 'int *' 'void *'; do
 for ac_arg1 in 'int' 'size_t' 'unsigned long' 'unsigned'; do
  for ac_arg5 in 'struct timeval *' 'const struct timeval *'; do
   AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
[#include <sys/types.h>
#if HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#if HAVE_SYS_SELECT_H
# include <sys/select.h>
#endif
#if HAVE_SYS_SOCKET_H
# include <sys/socket.h>
#endif
extern int select ($ac_arg1,$ac_arg234,$ac_arg234,$ac_arg234,$ac_arg5);])],
              [ac_cv_func_select_args="$ac_arg1,$ac_arg234,$ac_arg5"; break 3])
  done
 done
done
# Provide a safe default value.
: ${ac_cv_func_select_args='int,int *,struct timeval *'}
])
ac_save_IFS=$IFS; IFS=','
set dummy `echo "$ac_cv_func_select_args" | sed -e 's/\*/\*/g'`
IFS=$ac_save_IFS
shift
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG1, $[1],
                   [Define to the type of arg 1 for `select'.])
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG234, ($[2]),
                   [Define to the type of args 2, 3 and 4 for `select'.])
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG5, ($[3]),
                   [Define to the type of arg 5 for `select'.])
])# AC_FUNC_SELECT_ARGTYPES


# AC_FUNC_SETPGRP
# ---------------
AC_DEFUN([AC_FUNC_SETPGRP],
[AC_CACHE_CHECK(whether setpgrp takes no argument, ac_cv_func_setpgrp_void,
AC_TRY_RUN(
[#if HAVE_UNISTD_H
# include <unistd.h>
#endif

/* If this system has a BSD-style setpgrp, which takes arguments, exit
   successfully.  */

int
main ()
{
  if (setpgrp (1,1) == -1)
    exit (0);
  else
    exit (1);
}], ac_cv_func_setpgrp_void=no, ac_cv_func_setpgrp_void=yes,
   AC_MSG_ERROR(cannot check setpgrp if cross compiling))
)
if test $ac_cv_func_setpgrp_void = yes; then
  AC_DEFINE(SETPGRP_VOID, 1,
            [Define if the `setpgrp' function takes no argument.])
fi
])# AC_FUNC_SETPGRP


# AC_FUNC_STRERROR_R
# ------------------
AC_DEFUN([AC_FUNC_STRERROR_R],
[# Check strerror_r
AC_CHECK_FUNCS([strerror_r])
if test $ac_cv_func_strerror_r = yes; then
  AC_CHECK_HEADERS(string.h)
  AC_CACHE_CHECK([for working strerror_r],
                 ac_cv_func_strerror_r_works,
   [
    AC_TRY_COMPILE(
     [
#       include <stdio.h>
#       if HAVE_STRING_H
#        include <string.h>
#       endif
     ],
     [
       char buf;
       char x = *strerror_r (0, &buf, sizeof buf);
     ],
     ac_cv_func_strerror_r_works=yes,
     ac_cv_func_strerror_r_works=no
    )
    if test $ac_cv_func_strerror_r_works = yes; then
      AC_DEFINE_UNQUOTED(HAVE_WORKING_STRERROR_R, 1,
        [Define to 1 if `strerror_r' returns a string.])
    fi
  ])
fi
])# AC_FUNC_STRERROR_R


# AC_FUNC_STRFTIME
# ----------------
AC_DEFUN([AC_FUNC_STRFTIME],
[AC_CHECK_FUNCS(strftime, [],
[# strftime is in -lintl on SCO UNIX.
AC_CHECK_LIB(intl, strftime,
             [AC_DEFINE(HAVE_STRFTIME)
LIBS="-lintl $LIBS"])])dnl
])# AC_FUNC_STRFTIME


# AC_FUNC_VFORK
# -------------
AC_DEFUN([AC_FUNC_VFORK],
[AC_REQUIRE([AC_TYPE_PID_T])dnl
AC_CHECK_HEADERS(vfork.h)
AC_CACHE_CHECK(for working vfork, ac_cv_func_vfork_works,
[AC_TRY_RUN([/* Thanks to Paul Eggert for this test.  */
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#if HAVE_VFORK_H
# include <vfork.h>
#endif
/* On some sparc systems, changes by the child to local and incoming
   argument registers are propagated back to the parent.  The compiler
   is told about this with #include <vfork.h>, but some compilers
   (e.g. gcc -O) don't grok <vfork.h>.  Test for this by using a
   static variable whose address is put into a register that is
   clobbered by the vfork.  */
static
#ifdef __cplusplus
sparc_address_test (int arg)
# else
sparc_address_test (arg) int arg;
#endif
{
  static pid_t child;
  if (!child) {
    child = vfork ();
    if (child < 0) {
      perror ("vfork");
      _exit(2);
    }
    if (!child) {
      arg = getpid();
      write(-1, "", 0);
      _exit (arg);
    }
  }
}

int
main ()
{
  pid_t parent = getpid ();
  pid_t child;

  sparc_address_test ();

  child = vfork ();

  if (child == 0) {
    /* Here is another test for sparc vfork register problems.  This
       test uses lots of local variables, at least as many local
       variables as main has allocated so far including compiler
       temporaries.  4 locals are enough for gcc 1.40.3 on a Solaris
       4.1.3 sparc, but we use 8 to be safe.  A buggy compiler should
       reuse the register of parent for one of the local variables,
       since it will think that parent can't possibly be used any more
       in this routine.  Assigning to the local variable will thus
       munge parent in the parent process.  */
    pid_t
      p = getpid(), p1 = getpid(), p2 = getpid(), p3 = getpid(),
      p4 = getpid(), p5 = getpid(), p6 = getpid(), p7 = getpid();
    /* Convince the compiler that p..p7 are live; otherwise, it might
       use the same hardware register for all 8 local variables.  */
    if (p != p1 || p != p2 || p != p3 || p != p4
	|| p != p5 || p != p6 || p != p7)
      _exit(1);

    /* On some systems (e.g. IRIX 3.3), vfork doesn't separate parent
       from child file descriptors.  If the child closes a descriptor
       before it execs or exits, this munges the parent's descriptor
       as well.  Test for this by closing stdout in the child.  */
    _exit(close(fileno(stdout)) != 0);
  } else {
    int status;
    struct stat st;

    while (wait(&status) != child)
      ;
    exit(
	 /* Was there some problem with vforking?  */
	 child < 0

	 /* Did the child fail?  (This shouldn't happen.)  */
	 || status

	 /* Did the vfork/compiler bug occur?  */
	 || parent != getpid()

	 /* Did the file descriptor bug occur?  */
	 || fstat(fileno(stdout), &st) != 0
	 );
  }
}],
            [ac_cv_func_vfork_works=yes],
            [ac_cv_func_vfork_works=no],
            [AC_CHECK_FUNC(vfork)
ac_cv_func_vfork_works=$ac_cv_func_vfork])])
if test "x$ac_cv_func_vfork_works" = xno; then
  AC_DEFINE(vfork, fork, [Define as `fork' if `vfork' does not work.])
fi
])# AC_FUNC_VFORK


# AC_FUNC_VPRINTF
# ---------------
# Why the heck is that _doprnt does not define HAVE__DOPRNT???
# That the logical name!
AC_DEFUN([AC_FUNC_VPRINTF],
[AC_CHECK_FUNCS(vprintf, []
[AC_CHECK_FUNC(_doprnt,
               [AC_DEFINE(HAVE_DOPRNT, 1,
                          [Define if you don't have `vprintf' but do have
                          `_doprnt.'])])])
])


# AC_FUNC_WAIT3
# -------------
AC_DEFUN([AC_FUNC_WAIT3],
[AC_CACHE_CHECK(for wait3 that fills in rusage, ac_cv_func_wait3_rusage,
[AC_TRY_RUN(
[#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <stdio.h>
/* HP-UX has wait3 but does not fill in rusage at all.  */
int
main ()
{
  struct rusage r;
  int i;
  /* Use a field that we can force nonzero --
     voluntary context switches.
     For systems like NeXT and OSF/1 that don't set it,
     also use the system CPU time.  And page faults (I/O) for Linux.  */
  r.ru_nvcsw = 0;
  r.ru_stime.tv_sec = 0;
  r.ru_stime.tv_usec = 0;
  r.ru_majflt = r.ru_minflt = 0;
  switch (fork ())
    {
    case 0: /* Child.  */
      sleep(1); /* Give up the CPU.  */
      _exit(0);
    case -1: /* What can we do?  */
      _exit(0);
    default: /* Parent.  */
      wait3(&i, 0, &r);
      /* Avoid "text file busy" from rm on fast HP-UX machines.  */
      sleep(2);
      exit (r.ru_nvcsw == 0 && r.ru_majflt == 0 && r.ru_minflt == 0
	    && r.ru_stime.tv_sec == 0 && r.ru_stime.tv_usec == 0);
    }
}], ac_cv_func_wait3_rusage=yes, ac_cv_func_wait3_rusage=no,
ac_cv_func_wait3_rusage=no)])
if test $ac_cv_func_wait3_rusage = yes; then
  AC_DEFINE(HAVE_WAIT3, 1,
            [Define if you have the `wait3' system call.])
fi
])# AC_FUNC_WAIT3


# AC_FUNC_UTIME_NULL
# ------------------
AC_DEFUN([AC_FUNC_UTIME_NULL],
[AC_CACHE_CHECK(whether utime accepts a null argument, ac_cv_func_utime_null,
[rm -f conftestdata; >conftestdata
# Sequent interprets utime(file, 0) to mean use start of epoch.  Wrong.
AC_TRY_RUN(
[#include <sys/types.h>
#include <sys/stat.h>
int
main ()
{
  struct stat s, t;
  exit (!(stat ("conftestdata", &s) == 0
          && utime ("conftestdata", (long *)0) == 0
          && stat ("conftestdata", &t) == 0
          && t.st_mtime >= s.st_mtime
          && t.st_mtime - s.st_mtime < 120));
}], ac_cv_func_utime_null=yes, ac_cv_func_utime_null=no,
  ac_cv_func_utime_null=no)
rm -f core core.* *.core])
if test $ac_cv_func_utime_null = yes; then
  AC_DEFINE(HAVE_UTIME_NULL, 1,
            [Define if `utime(file, NULL)' sets file's timestamp to the
             present.])
fi
])# AC_FUNC_UTIME_NULL


# AC_FUNC_STRCOLL
# ---------------
AC_DEFUN([AC_FUNC_STRCOLL],
[AC_CACHE_CHECK(for working strcoll, ac_cv_func_strcoll_works,
[AC_TRY_RUN([#include <string.h>
int
main ()
{
  exit (strcoll ("abc", "def") >= 0 ||
	strcoll ("ABC", "DEF") >= 0 ||
	strcoll ("123", "456") >= 0);
}], ac_cv_func_strcoll_works=yes, ac_cv_func_strcoll_works=no,
ac_cv_func_strcoll_works=no)])
if test $ac_cv_func_strcoll_works = yes; then
  AC_DEFINE(HAVE_STRCOLL, 1,
            [Define if you have the `strcoll' function and it is properly
             defined.])
fi
])# AC_FUNC_STRCOLL


# AC_FUNC_SETVBUF_REVERSED
# ------------------------
AC_DEFUN([AC_FUNC_SETVBUF_REVERSED],
[AC_CACHE_CHECK(whether setvbuf arguments are reversed,
  ac_cv_func_setvbuf_reversed,
[AC_TRY_RUN([#include <stdio.h>
/* If setvbuf has the reversed format, exit 0. */
int
main ()
{
  /* This call has the arguments reversed.
     A reversed system may check and see that the address of main
     is not _IOLBF, _IONBF, or _IOFBF, and return nonzero.  */
  if (setvbuf(stdout, _IOLBF, (char *) main, BUFSIZ) != 0)
    exit(1);
  putc('\r', stdout);
  exit(0);			/* Non-reversed systems segv here.  */
}], ac_cv_func_setvbuf_reversed=yes, ac_cv_func_setvbuf_reversed=no)
rm -f core core.* *.core])
if test $ac_cv_func_setvbuf_reversed = yes; then
  AC_DEFINE(SETVBUF_REVERSED, 1,
            [Define if the `setvbuf' function takes the buffering type as
             its second argument and the buffer pointer as the third, as on
             System V before release 3.])
fi
])# AC_FUNC_SETVBUF_REVERSED





## ------------------------------ ##
## Checks for structure members.  ##
## ------------------------------ ##


# AC_STRUCT_TM
# ------------
# FIXME: This macro is badly named, it should be AC_CHECK_TYPE_STRUCT_TM.
# Or something else, but what? AC_CHECK_TYPE_STRUCT_TM_IN_SYS_TIME?
AC_DEFUN([AC_STRUCT_TM],
[AC_CACHE_CHECK([whether struct tm is in sys/time.h or time.h],
  ac_cv_struct_tm,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <sys/types.h>
#include <time.h>
],
                                    [struct tm *tp; tp->tm_sec;])],
                   [ac_cv_struct_tm=time.h],
                   [ac_cv_struct_tm=sys/time.h])])
if test $ac_cv_struct_tm = sys/time.h; then
  AC_DEFINE(TM_IN_SYS_TIME, 1,
            [Define if your <sys/time.h> declares `struct tm'.])
fi
])# AC_STRUCT_TM


# AC_STRUCT_TIMEZONE
# ------------------
# Figure out how to get the current timezone.  If `struct tm' has a
# `tm_zone' member, define `HAVE_TM_ZONE'.  Otherwise, if the
# external array `tzname' is found, define `HAVE_TZNAME'.
AC_DEFUN([AC_STRUCT_TIMEZONE],
[AC_REQUIRE([AC_STRUCT_TM])dnl
AC_CHECK_MEMBERS([struct tm.tm_zone],,,[#include <sys/types.h>
#include <$ac_cv_struct_tm>
])
if test "$ac_cv_member_struct_tm_tm_zone" = yes; then
  AC_DEFINE(HAVE_TM_ZONE, 1,
            [Define if your `struct tm' has `tm_zone'. Deprecated, use
             `HAVE_STRUCT_TM_TM_ZONE' instead.])
else
  AC_CACHE_CHECK(for tzname, ac_cv_var_tzname,
[AC_TRY_LINK(
[#include <time.h>
#ifndef tzname /* For SGI.  */
extern char *tzname[]; /* RS6000 and others reject char **tzname.  */
#endif
],
[atoi(*tzname);], ac_cv_var_tzname=yes, ac_cv_var_tzname=no)])
  if test $ac_cv_var_tzname = yes; then
    AC_DEFINE(HAVE_TZNAME, 1,
              [Define if you don't have `tm_zone' but do have the external
               array `tzname'.])
  fi
fi
])# AC_STRUCT_TIMEZONE



# FIXME: The following three macros should no longer be supported in the
# future.  They made sense when there was no means to directly check for
# members of aggregates.


# AC_STRUCT_ST_BLKSIZE
# --------------------
AU_DEFUN([AC_STRUCT_ST_BLKSIZE],
[AC_WARNING([$0:
        your code should no longer depend upon `HAVE_ST_BLKSIZE', but
        `HAVE_STRUCT_STAT_ST_BLKSIZE'.  Remove this AC_WARNING and
        the `AC_DEFINE' when you adjust the code.])
AC_CHECK_MEMBERS([struct stat.st_blksize],
                  [AC_DEFINE(HAVE_ST_BLKSIZE, 1,
                             [Define if your `struct stat' has
                              `st_blksize'.  Deprecated, use
                              `HAVE_STRUCT_STAT_ST_BLKSIZE' instead.])],,
                  [#include <sys/types.h>
#include <sys/stat.h>
])dnl
])# AC_STRUCT_ST_BLKSIZE


# AC_STRUCT_ST_BLOCKS
# -------------------
# If `struct stat' contains an `st_blocks' member, define
# HAVE_STRUCT_STAT_ST_BLOCKS.  Otherwise, add `fileblocks.o' to the
# output variable LIBOBJS.  We still define HAVE_ST_BLOCKS for backward
# compatibility.  In the future, we will activate specializations for
# this macro, so don't obsolete it right now.
#
# AC_OBSOLETE([$0], [; replace it with
#   AC_CHECK_MEMBERS([struct stat.st_blocks],
#                     [AC_LIBOBJ([fileblocks])])
# Please note that it will define `HAVE_STRUCT_STAT_ST_BLOCKS',
# and not `HAVE_ST_BLOCKS'.])dnl
#
AC_DEFUN([AC_STRUCT_ST_BLOCKS],
[AC_CHECK_MEMBERS([struct stat.st_blocks],
                  [AC_DEFINE(HAVE_ST_BLOCKS, 1,
                             [Define if your `struct stat' has
                              `st_blocks'.  Deprecated, use
                              `HAVE_STRUCT_STAT_ST_BLOCKS' instead.])],
                  [AC_LIBOBJ([fileblocks])],
                  [#include <sys/types.h>
#include <sys/stat.h>
])dnl
])# AC_STRUCT_ST_BLOCKS


# AC_STRUCT_ST_RDEV
# -----------------
AU_DEFUN([AC_STRUCT_ST_RDEV],
[AC_WARNING([$0:
        your code should no longer depend upon `HAVE_ST_RDEV', but
        `HAVE_STRUCT_STAT_ST_RDEV'.  Remove this AC_WARNING and
        the `AC_DEFINE' when you adjust the code.])
AC_CHECK_MEMBERS([struct stat.st_rdev],
                 [AC_DEFINE(HAVE_ST_RDEV, 1,
                            [Define if your `struct stat' has `st_rdev'.
                             Deprecated, use `HAVE_STRUCT_STAT_ST_RDEV'
                             instead.])],,
                  [#include <sys/types.h>
#include <sys/stat.h>
])dnl
])# AC_STRUCT_ST_RDEV





## -------------------------------------- ##
## Checks for operating system services.  ##
## -------------------------------------- ##


# AC_SYS_INTERPRETER
# ------------------
AC_DEFUN([AC_SYS_INTERPRETER],
[AC_CACHE_CHECK(whether @%:@! works in shell scripts, ac_cv_sys_interpreter,
[echo '#! /bin/cat
exit 69
' >conftest
chmod u+x conftest
(SHELL=/bin/sh; export SHELL; ./conftest >/dev/null)
if test $? -ne 69; then
   ac_cv_sys_interpreter=yes
else
   ac_cv_sys_interpreter=no
fi
rm -f conftest])
interpval=$ac_cv_sys_interpreter
])


AC_DEFUNCT([AC_HAVE_POUNDBANG], [;use AC_SYS_INTERPRETER, taking no arguments])
AC_DEFUNCT([AC_ARG_ARRAY], [; don't do unportable things with arguments])


# _AC_SYS_LARGEFILE_SOURCE(PROLOGUE, BODY)
# ----------------------------------------
define([_AC_SYS_LARGEFILE_SOURCE],
[AC_LANG_PROGRAM(
[$1
@%:@include <sys/types.h>
int a[[(off_t) 9223372036854775807 == 9223372036854775807 ? 1 : -1]];],
[$2])])


# _AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE,
#                               CACHE-VAR,
#                               DESCRIPTION,
#                               [INCLUDES], [FUNCTION-BODY])
# ----------------------------------------------------------
define([_AC_SYS_LARGEFILE_MACRO_VALUE],
[AC_CACHE_CHECK([for $1 value needed for large files], [$3],
[while :; do
  $3=no
  AC_COMPILE_IFELSE([_AC_SYS_LARGEFILE_SOURCE([$5], [$6])],
  		    [break])
  AC_COMPILE_IFELSE([_AC_SYS_LARGEFILE_SOURCE([@%:@define $1 $2
$5], [$6])],
  		    [$3=$2; break])
  break
done])
if test "$$3" != no; then
  AC_DEFINE_UNQUOTED([$1], [$$3], [$4])
fi[]dnl
])# _AC_SYS_LARGEFILE_MACRO_VALUE


# AC_SYS_LARGEFILE
# ----------------
# By default, many hosts won't let programs access large files;
# one must use special compiler options to get large-file access to work.
# For more details about this brain damage please see:
# http://www.sas.com/standards/large.file/x_open.20Mar96.html
AC_DEFUN([AC_SYS_LARGEFILE],
[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 "$GCC" != yes; then
       ac_save_CC=${CC-cc}
       while :; do
     	 # IRIX 6.2 and later do not support large files by default,
     	 # so use the C compiler's -n32 option if that helps.
     	 AC_COMPILE_IFELSE([_AC_SYS_LARGEFILE_SOURCE()],
     			   [break])
     	 CC="$CC -n32"
     	 AC_COMPILE_IFELSE([_AC_SYS_LARGEFILE_SOURCE()],
     			   [ac_cv_sys_largefile_CC=' -n32'; break])
         break
       done
       CC=$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_MACRO_VALUE(_LARGEFILE_SOURCE, 1,
    ac_cv_sys_largefile_source,
    [Define to make ftello visible on some hosts (e.g. HP-UX 10.20).],
    [@%:@include <stdio.h>], [return !ftello;])
  _AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,
    ac_cv_sys_large_files,
    [Define for large files, on AIX-style hosts.])
  _AC_SYS_LARGEFILE_MACRO_VALUE(_XOPEN_SOURCE, 500,
    ac_cv_sys_xopen_source,
    [Define to make ftello visible on some hosts (e.g. glibc 2.1.3).],
    [@%:@include <stdio.h>], [return !ftello;])
fi
])# AC_SYS_LARGEFILE


# AC_SYS_LONG_FILE_NAMES
# ----------------------
# Security: use a temporary directory as the most portable way of
# creating files in /tmp securely.  Removing them leaves a race
# condition, set -C is not portably guaranteed to use O_EXCL, so still
# leaves a race, and not all systems have the `mktemp' utility.  We
# still test for existence first in case of broken systems where the
# mkdir succeeds even when the directory exists.  Broken systems may
# retain a race, but they probably have other security problems
# anyway; this should be secure on well-behaved systems.  In any case,
# use of `mktemp' is probably inappropriate here since it would fail in
# attempting to create different file names differing after the 14th
# character on file systems without long file names.
AC_DEFUN([AC_SYS_LONG_FILE_NAMES],
[AC_CACHE_CHECK(for long file names, ac_cv_sys_long_file_names,
[ac_cv_sys_long_file_names=yes
# Test for long file names in all the places we know might matter:
#      .		the current directory, where building will happen
#      $prefix/lib	where we will be installing things
#      $exec_prefix/lib	likewise
# eval it to expand exec_prefix.
#      $TMPDIR		if set, where it might want to write temporary files
# if $TMPDIR is not set:
#      /tmp		where it might want to write temporary files
#      /var/tmp		likewise
#      /usr/tmp		likewise
if test -n "$TMPDIR" && test -d "$TMPDIR" && test -w "$TMPDIR"; then
  ac_tmpdirs=$TMPDIR
else
  ac_tmpdirs='/tmp /var/tmp /usr/tmp'
fi
for ac_dir in  . $ac_tmpdirs `eval echo $prefix/lib $exec_prefix/lib` ; do
  test -d $ac_dir || continue
  test -w $ac_dir || continue # It is less confusing to not echo anything here.
  ac_xdir=$ac_dir/cf$$
  (umask 077 && mkdir $ac_xdir 2>/dev/null) || continue
  ac_tf1=$ac_xdir/conftest9012345
  ac_tf2=$ac_xdir/conftest9012346
  (echo 1 >$ac_tf1) 2>/dev/null
  (echo 2 >$ac_tf2) 2>/dev/null
  ac_val=`cat $ac_tf1 2>/dev/null`
  if test ! -f $ac_tf1 || test "$ac_val" != 1; then
    ac_cv_sys_long_file_names=no
    rm -rf $ac_xdir 2>/dev/null
    break
  fi
  rm -rf $ac_xdir 2>/dev/null
done])
if test $ac_cv_sys_long_file_names = yes; then
  AC_DEFINE(HAVE_LONG_FILE_NAMES, 1,
            [Define if you support file names longer than 14 characters.])
fi
])


# AC_SYS_RESTARTABLE_SYSCALLS
# ---------------------------
# If the system automatically restarts a system call that is
# interrupted by a signal, define `HAVE_RESTARTABLE_SYSCALLS'.
AC_DEFUN([AC_SYS_RESTARTABLE_SYSCALLS],
[AC_REQUIRE([AC_HEADER_SYS_WAIT])dnl
AC_CHECK_HEADERS(unistd.h)
AC_CACHE_CHECK(for restartable system calls, ac_cv_sys_restartable_syscalls,
[AC_TRY_RUN(
[/* Exit 0 (true) if wait returns something other than -1,
   i.e. the pid of the child, which means that wait was restarted
   after getting the signal.  */

#include <sys/types.h>
#include <signal.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#if HAVE_SYS_WAIT_H
# include <sys/wait.h>
#endif

/* Some platforms explicitly require an extern "C" signal handler
   when using C++. */
#ifdef __cplusplus
extern "C" void ucatch (int dummy) { }
#else
void ucatch (dummy) int dummy; { }
#endif

int
main ()
{
  int i = fork (), status;

  if (i == 0)
    {
      sleep (3);
      kill (getppid (), SIGINT);
      sleep (3);
      exit (0);
    }

  signal (SIGINT, ucatch);

  status = wait (&i);
  if (status == -1)
    wait (&i);

  exit (status == -1);
}], ac_cv_sys_restartable_syscalls=yes, ac_cv_sys_restartable_syscalls=no)])
if test $ac_cv_sys_restartable_syscalls = yes; then
  AC_DEFINE(HAVE_RESTARTABLE_SYSCALLS, 1,
            [Define if system calls automatically restart after interruption
             by a signal.])
fi
])# AC_SYS_RESTARTABLE_SYSCALLS




## --------------------- ##
## Checks for X window.  ##
## --------------------- ##


# AC_PATH_X
# ---------
# If we find X, set shell vars x_includes and x_libraries to the
# paths, otherwise set no_x=yes.
# Uses ac_ vars as temps to allow command line to override cache and checks.
# --without-x overrides everything else, but does not touch the cache.
AC_DEFUN([AC_PATH_X],
[AC_REQUIRE_CPP()dnl Set CPP; we run _AC_PATH_X_DIRECT conditionally.
AC_MSG_CHECKING(for X)

dnl Document the X abnormal options inherited from history.
AC_EXPAND_ONCE([AC_DIVERT([HELP_BEGIN],
[
X features:
  --x-includes=DIR    X include files are in DIR
  --x-libraries=DIR   X library files are in DIR])])dnl

AC_ARG_WITH(x, [  --with-x                use the X Window System])
# $have_x is `yes', `no', `disabled', or empty when we do not yet know.
if test "x$with_x" = xno; then
  # The user explicitly disabled X.
  have_x=disabled
else
  if test "x$x_includes" != xNONE && test "x$x_libraries" != xNONE; then
    # Both variables are already set.
    have_x=yes
  else
AC_CACHE_VAL(ac_cv_have_x,
[# One or both of the vars are not set, and there is no cached value.
ac_x_includes=no ac_x_libraries=no
_AC_PATH_X_XMKMF
_AC_PATH_X_DIRECT
if test "$ac_x_includes" = no || test "$ac_x_libraries" = no; then
  # Didn't find X anywhere.  Cache the known absence of X.
  ac_cv_have_x="have_x=no"
else
  # Record where we found X for the cache.
  ac_cv_have_x="have_x=yes \
	        ac_x_includes=$ac_x_includes ac_x_libraries=$ac_x_libraries"
fi])dnl
  fi
  eval "$ac_cv_have_x"
fi # $with_x != no

if test "$have_x" != yes; then
  AC_MSG_RESULT($have_x)
  no_x=yes
else
  # If each of the values was on the command line, it overrides each guess.
  test "x$x_includes" = xNONE && x_includes=$ac_x_includes
  test "x$x_libraries" = xNONE && x_libraries=$ac_x_libraries
  # Update the cache value to reflect the command line values.
  ac_cv_have_x="have_x=yes \
		ac_x_includes=$x_includes ac_x_libraries=$x_libraries"
  AC_MSG_RESULT([libraries $x_libraries, headers $x_includes])
fi
])# AC_PATH_X


# _AC_PATH_X_XMKMF
# ---------------
# Internal subroutine of AC_PATH_X.
# Set ac_x_includes and/or ac_x_libraries.
AC_DEFUN([_AC_PATH_X_XMKMF],
[rm -fr conftestdir
if mkdir conftestdir; then
  cd conftestdir
  # Make sure to not put "make" in the Imakefile rules, since we grep it out.
  cat >Imakefile <<'EOF'
acfindx:
	@echo 'ac_im_incroot="${INCROOT}"; ac_im_usrlibdir="${USRLIBDIR}"; ac_im_libdir="${LIBDIR}"'
EOF
  if (xmkmf) >/dev/null 2>/dev/null && test -f Makefile; then
    # GNU make sometimes prints "make[1]: Entering...", which would confuse us.
    eval `${MAKE-make} acfindx 2>/dev/null | grep -v make`
    # Open Windows xmkmf reportedly sets LIBDIR instead of USRLIBDIR.
    for ac_extension in a so sl; do
      if test ! -f $ac_im_usrlibdir/libX11.$ac_extension &&
         test -f $ac_im_libdir/libX11.$ac_extension; then
        ac_im_usrlibdir=$ac_im_libdir; break
      fi
    done
    # Screen out bogus values from the imake configuration.  They are
    # bogus both because they are the default anyway, and because
    # using them would break gcc on systems where it needs fixed includes.
    case $ac_im_incroot in
	/usr/include) ;;
	*) test -f "$ac_im_incroot/X11/Xos.h" && ac_x_includes=$ac_im_incroot;;
    esac
    case $ac_im_usrlibdir in
	/usr/lib | /lib) ;;
	*) test -d "$ac_im_usrlibdir" && ac_x_libraries=$ac_im_usrlibdir ;;
    esac
  fi
  cd ..
  rm -fr conftestdir
fi
])# _AC_PATH_X_XMKMF


# _AC_PATH_X_DIRECT
# ----------------
# Internal subroutine of AC_PATH_X.
# Set ac_x_includes and/or ac_x_libraries.
AC_DEFUN([_AC_PATH_X_DIRECT],
[# Standard set of common directories for X headers.
# Check X11 before X11Rn because it is often a symlink to the current release.
ac_x_header_dirs='
/usr/X11/include
/usr/X11R6/include
/usr/X11R5/include
/usr/X11R4/include

/usr/include/X11
/usr/include/X11R6
/usr/include/X11R5
/usr/include/X11R4

/usr/local/X11/include
/usr/local/X11R6/include
/usr/local/X11R5/include
/usr/local/X11R4/include

/usr/local/include/X11
/usr/local/include/X11R6
/usr/local/include/X11R5
/usr/local/include/X11R4

/usr/X386/include
/usr/x386/include
/usr/XFree86/include/X11

/usr/include
/usr/local/include
/usr/unsupported/include
/usr/athena/include
/usr/local/x11r5/include
/usr/lpp/Xamples/include

/usr/openwin/include
/usr/openwin/share/include'

if test "$ac_x_includes" = no; then
  # Guess where to find include files, by looking for Intrinsic.h.
  # First, try using that file with no special directory specified.
  AC_TRY_CPP([@%:@include <X11/Intrinsic.h>],
[# We can compile using X headers with no special include directory.
ac_x_includes=],
[for ac_dir in $ac_x_header_dirs; do
  if test -r "$ac_dir/X11/Intrinsic.h"; then
    ac_x_includes=$ac_dir
    break
  fi
done])
fi # $ac_x_includes = no

if test "$ac_x_libraries" = no; then
  # Check for the libraries.
  # See if we find them without any special options.
  # Don't add to $LIBS permanently.
  ac_save_LIBS=$LIBS
  LIBS="-lXt $LIBS"
  AC_TRY_LINK([@%:@include <X11/Intrinsic.h>], [XtMalloc (0)],
[LIBS=$ac_save_LIBS
# We can link X programs with no special library path.
ac_x_libraries=],
[LIBS=$ac_save_LIBS
for ac_dir in `echo "$ac_x_includes $ac_x_header_dirs" | sed s/include/lib/g`
do
  # Don't even attempt the hair of trying to link an X program!
  for ac_extension in a so sl; do
    if test -r $ac_dir/libXt.$ac_extension; then
      ac_x_libraries=$ac_dir
      break 2
    fi
  done
done])
fi # $ac_x_libraries = no
])# _AC_PATH_X_DIRECT


# AC_PATH_XTRA
# ------------
# Find additional X libraries, magic flags, etc.
AC_DEFUN([AC_PATH_XTRA],
[AC_REQUIRE([AC_PATH_X])dnl
if test "$no_x" = yes; then
  # Not all programs may use this symbol, but it does not hurt to define it.
  AC_DEFINE(X_DISPLAY_MISSING, 1,
            [Define if the X Window System is missing or not being used.])
  X_CFLAGS= X_PRE_LIBS= X_LIBS= X_EXTRA_LIBS=
else
  if test -n "$x_includes"; then
    X_CFLAGS="$X_CFLAGS -I$x_includes"
  fi

  # It would also be nice to do this for all -L options, not just this one.
  if test -n "$x_libraries"; then
    X_LIBS="$X_LIBS -L$x_libraries"
dnl FIXME: banish uname from this macro!
    # For Solaris; some versions of Sun CC require a space after -R and
    # others require no space.  Words are not sufficient . . . .
    case `(uname -sr) 2>/dev/null` in
    "SunOS 5"*)
      AC_MSG_CHECKING(whether -R must be followed by a space)
      ac_xsave_LIBS=$LIBS; LIBS="$LIBS -R$x_libraries"
      AC_LINK_IFELSE([], ac_R_nospace=yes, ac_R_nospace=no)
      if test $ac_R_nospace = yes; then
	AC_MSG_RESULT(no)
	X_LIBS="$X_LIBS -R$x_libraries"
      else
	LIBS="$ac_xsave_LIBS -R $x_libraries"
	AC_LINK_IFELSE([], ac_R_space=yes, ac_R_space=no)
	if test $ac_R_space = yes; then
	  AC_MSG_RESULT(yes)
	  X_LIBS="$X_LIBS -R $x_libraries"
	else
	  AC_MSG_RESULT(neither works)
	fi
      fi
      LIBS=$ac_xsave_LIBS
    esac
  fi

  # Check for system-dependent libraries X programs must link with.
  # Do this before checking for the system-independent R6 libraries
  # (-lICE), since we may need -lsocket or whatever for X linking.

  if test "$ISC" = yes; then
    X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl_s -linet"
  else
    # Martyn Johnson says this is needed for Ultrix, if the X
    # libraries were built with DECnet support.  And Karl Berry says
    # the Alpha needs dnet_stub (dnet does not exist).
    AC_CHECK_LIB(dnet, dnet_ntoa, [X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet"])
    if test $ac_cv_lib_dnet_dnet_ntoa = no; then
      AC_CHECK_LIB(dnet_stub, dnet_ntoa,
	[X_EXTRA_LIBS="$X_EXTRA_LIBS -ldnet_stub"])
    fi

    # msh@cis.ufl.edu says -lnsl (and -lsocket) are needed for his 386/AT,
    # to get the SysV transport functions.
    # Chad R. Larson says the Pyramis MIS-ES running DC/OSx (SVR4)
    # needs -lnsl.
    # The nsl library prevents programs from opening the X display
    # on Irix 5.2, according to T.E. Dickey.
    # The functions gethostbyname, getservbyname, and inet_addr are
    # in -lbsd on LynxOS 3.0.1/i386, according to Lars Hecking.
    AC_CHECK_FUNC(gethostbyname)
    if test $ac_cv_func_gethostbyname = no; then
      AC_CHECK_LIB(nsl, gethostbyname, X_EXTRA_LIBS="$X_EXTRA_LIBS -lnsl")
      if test $ac_cv_lib_nsl_gethostbyname = no; then
        AC_CHECK_LIB(bsd, gethostbyname, X_EXTRA_LIBS="$X_EXTRA_LIBS -lbsd")
      fi
    fi

    # lieder@skyler.mavd.honeywell.com says without -lsocket,
    # socket/setsockopt and other routines are undefined under SCO ODT
    # 2.0.  But -lsocket is broken on IRIX 5.2 (and is not necessary
    # on later versions), says Simon Leinen: it contains gethostby*
    # variants that don't use the nameserver (or something).  -lsocket
    # must be given before -lnsl if both are needed.  We assume that
    # if connect needs -lnsl, so does gethostbyname.
    AC_CHECK_FUNC(connect)
    if test $ac_cv_func_connect = no; then
      AC_CHECK_LIB(socket, connect, X_EXTRA_LIBS="-lsocket $X_EXTRA_LIBS", ,
	$X_EXTRA_LIBS)
    fi

    # Guillermo Gomez says -lposix is necessary on A/UX.
    AC_CHECK_FUNC(remove)
    if test $ac_cv_func_remove = no; then
      AC_CHECK_LIB(posix, remove, X_EXTRA_LIBS="$X_EXTRA_LIBS -lposix")
    fi

    # BSDI BSD/OS 2.1 needs -lipc for XOpenDisplay.
    AC_CHECK_FUNC(shmat)
    if test $ac_cv_func_shmat = no; then
      AC_CHECK_LIB(ipc, shmat, X_EXTRA_LIBS="$X_EXTRA_LIBS -lipc")
    fi
  fi

  # Check for libraries that X11R6 Xt/Xaw programs need.
  ac_save_LDFLAGS=$LDFLAGS
  test -n "$x_libraries" && LDFLAGS="$LDFLAGS -L$x_libraries"
  # SM needs ICE to (dynamically) link under SunOS 4.x (so we have to
  # check for ICE first), but we must link in the order -lSM -lICE or
  # we get undefined symbols.  So assume we have SM if we have ICE.
  # These have to be linked with before -lX11, unlike the other
  # libraries we check for below, so use a different variable.
  # John Interrante, Karl Berry
  AC_CHECK_LIB(ICE, IceConnectionNumber,
    [X_PRE_LIBS="$X_PRE_LIBS -lSM -lICE"], , $X_EXTRA_LIBS)
  LDFLAGS=$ac_save_LDFLAGS

fi
AC_SUBST(X_CFLAGS)dnl
AC_SUBST(X_PRE_LIBS)dnl
AC_SUBST(X_LIBS)dnl
AC_SUBST(X_EXTRA_LIBS)dnl
])# AC_PATH_XTRA



## ------------------------------------ ##
## Checks for not-quite-Unix variants.  ##
## ------------------------------------ ##



# _AC_CYGWIN
# ----------
# Check for Cygwin.  This is a way to set the right value for
# EXEEXT.
define([_AC_CYGWIN],
[AC_CACHE_CHECK(for Cygwin environment, ac_cv_cygwin,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([],
[#ifndef __CYGWIN__
# define __CYGWIN__ __CYGWIN32__
#endif
return __CYGWIN__;])],
                   [ac_cv_cygwin=yes],
                   [ac_cv_cygwin=no])])
test "$ac_cv_cygwin" = yes && CYGWIN=yes[]dnl
])# _AC_CYGWIN


# _AC_EMXOS2
# ----------
# Check for EMX on OS/2.  This is another way to set the right value
# for EXEEXT.
define([_AC_EMXOS2],
[AC_CACHE_CHECK(for EMX OS/2 environment, ac_cv_emxos2,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [return __EMX__;])],
                   [ac_cv_emxos2=yes],
                   [ac_cv_emxos2=no])])
test "$ac_cv_emxos2" = yes && EMXOS2=yes[]dnl
])# _AC_EMXOS2


# _AC_MINGW32
# -----------
# Check for mingw32.  This is another way to set the right value for
# EXEEXT.
define([_AC_MINGW32],
[AC_CACHE_CHECK(for mingw32 environment, ac_cv_mingw32,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [return __MINGW32__;])],
                   [ac_cv_mingw32=yes],
                   [ac_cv_mingw32=no])])
test "$ac_cv_mingw32" = yes && MINGW32=yes[]dnl
])# _AC_MINGW32


# The user is no longer supposed to call these macros.
AU_DEFUN([AC_CYGWIN],   [])
AU_DEFUN([AC_CYGWIN32], [])
AU_DEFUN([AC_EMXOS2],   [])
AU_DEFUN([AC_MING32],   [])


# We must not AU define them, because autoupdate would them remove
# them, which is right, but Automake 1.4 would remove the support for
# $(EXEEXT) etc.
# FIXME: Remove this once Automake fixed.
AC_DEFUN([AC_EXEEXT],   [])
AC_DEFUN([AC_OBJEXT],   [])


# _AC_EXEEXT
# -_--------
# Check for the extension used for executables.  This knows that we
# add .exe for Cygwin or mingw32.  Otherwise, it compiles a test
# executable.  If this is called, the executable extensions will be
# automatically used by link commands run by the configure script.
define([_AC_EXEEXT],
[_AC_CYGWIN
_AC_MINGW32
_AC_EMXOS2
AC_CACHE_CHECK([for executable suffix], ac_cv_exeext,
[if test "$CYGWIN" = yes || test "$MINGW32" = yes || test "$EMXOS2" = yes; then
  ac_cv_exeext=.exe
else
  AC_LINK_IFELSE([AC_LANG_PROGRAM()],
  [for ac_file in conftest.*; do
     case $ac_file in
       *.$ac_ext | *.o | *.obj | *.xcoff) ;;
       *) ac_cv_exeext=`echo $ac_file | sed -e s/conftest//` ;;
     esac
   done],
  [AC_MSG_ERROR([cannot compile and link])])
  test -n "$ac_cv_exeext" && ac_cv_exeext=no
fi])
EXEEXT=
test "$ac_cv_exeext" != no && EXEEXT=$ac_cv_exeext
dnl Setting ac_exeext will implicitly change the ac_link command.
ac_exeext=$EXEEXT
AC_SUBST(EXEEXT)dnl
])# _AC_EXEEXT


# _AC_OBJEXT
# ----------
# Check the object extension used by the compiler: typically .o or
# .obj.  If this is called, some other behaviour will change,
# determined by ac_objext.
define([_AC_OBJEXT],
[AC_CACHE_CHECK([for object suffix], ac_cv_objext,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
   [for ac_file in conftest.*; do
    case $ac_file in
      *.$ac_ext) ;;
      *) ac_cv_objext=`echo $ac_file | sed -e s/conftest.//` ;;
    esac
  done],
   [AC_MSG_ERROR([cannot compile])])])
AC_SUBST(OBJEXT, $ac_cv_objext)dnl
ac_objext=$ac_cv_objext
])# _AC_OBJEXT



## -------------------------- ##
## Checks for UNIX variants.  ##
## -------------------------- ##


# These are kludges which should be replaced by a single POSIX check.
# They aren't cached, to discourage their use.

# AC_AIX
# ------
AC_DEFUN([AC_AIX],
[AH_VERBATIM([_ALL_SOURCE],
[/* Define if on AIX 3.
   System headers sometimes define this.
   We just want to avoid a redefinition error message.  */
#ifndef _ALL_SOURCE
# undef _ALL_SOURCE
#endif])dnl
AC_BEFORE([$0], [AC_TRY_COMPILE])dnl
AC_BEFORE([$0], [AC_TRY_RUN])dnl
AC_MSG_CHECKING(for AIX)
AC_EGREP_CPP(yes,
[#ifdef _AIX
  yes
#endif
],
[AC_MSG_RESULT(yes)
AC_DEFINE(_ALL_SOURCE)],
AC_MSG_RESULT(no))
])# AC_AIX


# AC_MINIX
# --------
AC_DEFUN([AC_MINIX],
[AC_BEFORE([$0], [AC_TRY_COMPILE])dnl
AC_BEFORE([$0], [AC_TRY_RUN])dnl
AC_CHECK_HEADER(minix/config.h, MINIX=yes, MINIX=)
if test "$MINIX" = yes; then
  AC_DEFINE(_POSIX_SOURCE, 1,
            [Define if you need to in order for `stat' and other things to
             work.])
  AC_DEFINE(_POSIX_1_SOURCE, 2,
            [Define if the system does not provide POSIX.1 features except
             with this defined.])
  AC_DEFINE(_MINIX, 1,
            [Define if on MINIX.])
fi
])# AC_MINIX


# AC_ISC_POSIX
# ------------
AC_DEFUN([AC_ISC_POSIX],
[AC_REQUIRE([AC_PROG_CC])dnl
AC_BEFORE([$0], [AC_TRY_COMPILE])dnl
AC_BEFORE([$0], [AC_TRY_RUN])dnl
AC_MSG_CHECKING(for POSIXized ISC)
if test -d /etc/conf/kconfig.d &&
   grep _POSIX_VERSION [/usr/include/sys/unistd.h] >/dev/null 2>&1
then
  AC_MSG_RESULT(yes)
  ISC=yes # If later tests want to check for ISC.
  AC_DEFINE(_POSIX_SOURCE, 1,
            [Define if you need to in order for stat and other things to
             work.])
  if test "$GCC" = yes; then
    CC="$CC -posix"
  else
    CC="$CC -Xp"
  fi
else
  AC_MSG_RESULT(no)
  ISC=
fi
])# AC_ISC_POSIX


# AC_XENIX_DIR
# ------------
AU_DEFUN(AC_XENIX_DIR,
[# You shouldn't need to depend upon XENIX.  Remove this test if useless.
AC_MSG_CHECKING(for Xenix)
AC_EGREP_CPP(yes,
[#if defined(M_XENIX) && !defined(M_UNIX)
  yes
@%:@endif],
             [AC_MSG_RESULT(yes); XENIX=yes],
             [AC_MSG_RESULT(no); XENIX=])

AC_HEADER_DIRENT[]dnl
])


# AC_DYNIX_SEQ
# ------------
AU_DEFUN([AC_DYNIX_SEQ], [AC_FUNC_GETMNTENT])


# AC_IRIX_SUN
# -----------
AU_DEFUN([AC_IRIX_SUN],
[AC_FUNC_GETMNTENT
AC_CHECK_LIB(sun, getpwnam)])


# AC_SCO_INTL
# -----------
AU_DEFUN([AC_SCO_INTL], [AC_FUNC_STRFTIME])