curl-functions.m4

    ])
  fi
  #
  if test "$tst_proto_siginterrupt" = "yes"; then
    AC_MSG_CHECKING([if siginterrupt is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_signal
      ]],[[
        if(0 != siginterrupt(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_siginterrupt="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_siginterrupt="no"
    ])
  fi
  #
  if test "$tst_compi_siginterrupt" = "yes"; then
    AC_MSG_CHECKING([if siginterrupt usage allowed])
    if test "x$curl_disallow_siginterrupt" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_siginterrupt="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_siginterrupt="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if siginterrupt might be used])
  if test "$tst_links_siginterrupt" = "yes" &&
     test "$tst_proto_siginterrupt" = "yes" &&
     test "$tst_compi_siginterrupt" = "yes" &&
     test "$tst_allow_siginterrupt" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_SIGINTERRUPT, 1,
      [Define to 1 if you have the siginterrupt function.])
    ac_cv_func_siginterrupt="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_siginterrupt="no"
  fi
])


dnl CURL_CHECK_FUNC_SIGNAL
dnl -------------------------------------------------
dnl Verify if signal is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_signal, then
dnl HAVE_SIGNAL will be defined.

AC_DEFUN([CURL_CHECK_FUNC_SIGNAL], [
  AC_REQUIRE([CURL_INCLUDES_SIGNAL])dnl
  #
  tst_links_signal="unknown"
  tst_proto_signal="unknown"
  tst_compi_signal="unknown"
  tst_allow_signal="unknown"
  #
  AC_MSG_CHECKING([if signal can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([signal])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_signal="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_signal="no"
  ])
  #
  if test "$tst_links_signal" = "yes"; then
    AC_MSG_CHECKING([if signal is prototyped])
    AC_EGREP_CPP([signal],[
      $curl_includes_signal
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_signal="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_signal="no"
    ])
  fi
  #
  if test "$tst_proto_signal" = "yes"; then
    AC_MSG_CHECKING([if signal is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_signal
      ]],[[
        if(0 != signal(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_signal="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_signal="no"
    ])
  fi
  #
  if test "$tst_compi_signal" = "yes"; then
    AC_MSG_CHECKING([if signal usage allowed])
    if test "x$curl_disallow_signal" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_signal="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_signal="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if signal might be used])
  if test "$tst_links_signal" = "yes" &&
     test "$tst_proto_signal" = "yes" &&
     test "$tst_compi_signal" = "yes" &&
     test "$tst_allow_signal" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_SIGNAL, 1,
      [Define to 1 if you have the signal function.])
    ac_cv_func_signal="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_signal="no"
  fi
])


dnl CURL_CHECK_FUNC_SIGSETJMP
dnl -------------------------------------------------
dnl Verify if sigsetjmp is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_sigsetjmp, then
dnl HAVE_SIGSETJMP will be defined.

AC_DEFUN([CURL_CHECK_FUNC_SIGSETJMP], [
  AC_REQUIRE([CURL_INCLUDES_SETJMP])dnl
  #
  tst_links_sigsetjmp="unknown"
  tst_macro_sigsetjmp="unknown"
  tst_proto_sigsetjmp="unknown"
  tst_compi_sigsetjmp="unknown"
  tst_allow_sigsetjmp="unknown"
  #
  AC_MSG_CHECKING([if sigsetjmp can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([sigsetjmp])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_sigsetjmp="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_sigsetjmp="no"
  ])
  #
  if test "$tst_links_sigsetjmp" = "no"; then
    AC_MSG_CHECKING([if sigsetjmp seems a macro])
    AC_LINK_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_setjmp
      ]],[[
        sigjmp_buf env;
        if(0 != sigsetjmp(env, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_macro_sigsetjmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_macro_sigsetjmp="no"
    ])
  fi
  #
  if test "$tst_links_sigsetjmp" = "yes"; then
    AC_MSG_CHECKING([if sigsetjmp is prototyped])
    AC_EGREP_CPP([sigsetjmp],[
      $curl_includes_setjmp
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_sigsetjmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_sigsetjmp="no"
    ])
  fi
  #
  if test "$tst_proto_sigsetjmp" = "yes" ||
     test "$tst_macro_sigsetjmp" = "yes"; then
    AC_MSG_CHECKING([if sigsetjmp is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_setjmp
      ]],[[
        sigjmp_buf env;
        if(0 != sigsetjmp(env, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_sigsetjmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_sigsetjmp="no"
    ])
  fi
  #
  if test "$tst_compi_sigsetjmp" = "yes"; then
    AC_MSG_CHECKING([if sigsetjmp usage allowed])
    if test "x$curl_disallow_sigsetjmp" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_sigsetjmp="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_sigsetjmp="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if sigsetjmp might be used])
  if (test "$tst_proto_sigsetjmp" = "yes" ||
      test "$tst_macro_sigsetjmp" = "yes") &&
     test "$tst_compi_sigsetjmp" = "yes" &&
     test "$tst_allow_sigsetjmp" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_SIGSETJMP, 1,
      [Define to 1 if you have the sigsetjmp function or macro.])
    ac_cv_func_sigsetjmp="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_sigsetjmp="no"
  fi
])


dnl CURL_CHECK_FUNC_SOCKET
dnl -------------------------------------------------
dnl Verify if socket is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_socket, then
dnl HAVE_SOCKET will be defined.

AC_DEFUN([CURL_CHECK_FUNC_SOCKET], [
  AC_REQUIRE([CURL_INCLUDES_WINSOCK2])dnl
  AC_REQUIRE([CURL_INCLUDES_SYS_SOCKET])dnl
  AC_REQUIRE([CURL_INCLUDES_SOCKET])dnl
  #
  tst_links_socket="unknown"
  tst_proto_socket="unknown"
  tst_compi_socket="unknown"
  tst_allow_socket="unknown"
  #
  AC_MSG_CHECKING([if socket can be linked])
  AC_LINK_IFELSE([
    AC_LANG_PROGRAM([[
      $curl_includes_winsock2
      $curl_includes_sys_socket
      $curl_includes_socket
    ]],[[
      if(0 != socket(0, 0, 0))
        return 1;
    ]])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_socket="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_socket="no"
  ])
  #
  if test "$tst_links_socket" = "yes"; then
    AC_MSG_CHECKING([if socket is prototyped])
    AC_EGREP_CPP([socket],[
      $curl_includes_winsock2
      $curl_includes_sys_socket
      $curl_includes_socket
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_socket="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_socket="no"
    ])
  fi
  #
  if test "$tst_proto_socket" = "yes"; then
    AC_MSG_CHECKING([if socket is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_winsock2
        $curl_includes_sys_socket
        $curl_includes_socket
      ]],[[
        if(0 != socket(0, 0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_socket="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_socket="no"
    ])
  fi
  #
  if test "$tst_compi_socket" = "yes"; then
    AC_MSG_CHECKING([if socket usage allowed])
    if test "x$curl_disallow_socket" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_socket="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_socket="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if socket might be used])
  if test "$tst_links_socket" = "yes" &&
     test "$tst_proto_socket" = "yes" &&
     test "$tst_compi_socket" = "yes" &&
     test "$tst_allow_socket" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_SOCKET, 1,
      [Define to 1 if you have the socket function.])
    ac_cv_func_socket="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_socket="no"
  fi
])


dnl CURL_CHECK_FUNC_STRCASECMP
dnl -------------------------------------------------
dnl Verify if strcasecmp is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_strcasecmp, then
dnl HAVE_STRCASECMP will be defined.

AC_DEFUN([CURL_CHECK_FUNC_STRCASECMP], [
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_strcasecmp="unknown"
  tst_proto_strcasecmp="unknown"
  tst_compi_strcasecmp="unknown"
  tst_allow_strcasecmp="unknown"
  #
  AC_MSG_CHECKING([if strcasecmp can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([strcasecmp])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_strcasecmp="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_strcasecmp="no"
  ])
  #
  if test "$tst_links_strcasecmp" = "yes"; then
    AC_MSG_CHECKING([if strcasecmp is prototyped])
    AC_EGREP_CPP([strcasecmp],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_strcasecmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_strcasecmp="no"
    ])
  fi
  #
  if test "$tst_proto_strcasecmp" = "yes"; then
    AC_MSG_CHECKING([if strcasecmp is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != strcasecmp(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_strcasecmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_strcasecmp="no"
    ])
  fi
  #
  if test "$tst_compi_strcasecmp" = "yes"; then
    AC_MSG_CHECKING([if strcasecmp usage allowed])
    if test "x$curl_disallow_strcasecmp" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_strcasecmp="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_strcasecmp="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if strcasecmp might be used])
  if test "$tst_links_strcasecmp" = "yes" &&
     test "$tst_proto_strcasecmp" = "yes" &&
     test "$tst_compi_strcasecmp" = "yes" &&
     test "$tst_allow_strcasecmp" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_STRCASECMP, 1,
      [Define to 1 if you have the strcasecmp function.])
    ac_cv_func_strcasecmp="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_strcasecmp="no"
  fi
])


dnl CURL_CHECK_FUNC_STRCASESTR
dnl -------------------------------------------------
dnl Verify if strcasestr is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_strcasestr, then
dnl HAVE_STRCASESTR will be defined.

AC_DEFUN([CURL_CHECK_FUNC_STRCASESTR], [
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_strcasestr="unknown"
  tst_proto_strcasestr="unknown"
  tst_compi_strcasestr="unknown"
  tst_allow_strcasestr="unknown"
  #
  AC_MSG_CHECKING([if strcasestr can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([strcasestr])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_strcasestr="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_strcasestr="no"
  ])
  #
  if test "$tst_links_strcasestr" = "yes"; then
    AC_MSG_CHECKING([if strcasestr is prototyped])
    AC_EGREP_CPP([strcasestr],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_strcasestr="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_strcasestr="no"
    ])
  fi
  #
  if test "$tst_proto_strcasestr" = "yes"; then
    AC_MSG_CHECKING([if strcasestr is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != strcasestr(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_strcasestr="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_strcasestr="no"
    ])
  fi
  #
  if test "$tst_compi_strcasestr" = "yes"; then
    AC_MSG_CHECKING([if strcasestr usage allowed])
    if test "x$curl_disallow_strcasestr" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_strcasestr="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_strcasestr="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if strcasestr might be used])
  if test "$tst_links_strcasestr" = "yes" &&
     test "$tst_proto_strcasestr" = "yes" &&
     test "$tst_compi_strcasestr" = "yes" &&
     test "$tst_allow_strcasestr" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_STRCASESTR, 1,
      [Define to 1 if you have the strcasestr function.])
    ac_cv_func_strcasestr="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_strcasestr="no"
  fi
])


dnl CURL_CHECK_FUNC_STRCMPI
dnl -------------------------------------------------
dnl Verify if strcmpi is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_strcmpi, then
dnl HAVE_STRCMPI will be defined.

AC_DEFUN([CURL_CHECK_FUNC_STRCMPI], [
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_strcmpi="unknown"
  tst_proto_strcmpi="unknown"
  tst_compi_strcmpi="unknown"
  tst_allow_strcmpi="unknown"
  #
  AC_MSG_CHECKING([if strcmpi can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([strcmpi])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_strcmpi="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_strcmpi="no"
  ])
  #
  if test "$tst_links_strcmpi" = "yes"; then
    AC_MSG_CHECKING([if strcmpi is prototyped])
    AC_EGREP_CPP([strcmpi],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_strcmpi="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_strcmpi="no"
    ])
  fi
  #
  if test "$tst_proto_strcmpi" = "yes"; then
    AC_MSG_CHECKING([if strcmpi is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != strcmpi(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_strcmpi="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_strcmpi="no"
    ])
  fi
  #
  if test "$tst_compi_strcmpi" = "yes"; then
    AC_MSG_CHECKING([if strcmpi usage allowed])
    if test "x$curl_disallow_strcmpi" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_strcmpi="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_strcmpi="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if strcmpi might be used])
  if test "$tst_links_strcmpi" = "yes" &&
     test "$tst_proto_strcmpi" = "yes" &&
     test "$tst_compi_strcmpi" = "yes" &&
     test "$tst_allow_strcmpi" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_STRCMPI, 1,
      [Define to 1 if you have the strcmpi function.])
    ac_cv_func_strcmpi="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_strcmpi="no"
  fi
])


dnl CURL_CHECK_FUNC_STRDUP
dnl -------------------------------------------------
dnl Verify if strdup is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_strdup, then
dnl HAVE_STRDUP will be defined.

AC_DEFUN([CURL_CHECK_FUNC_STRDUP], [
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_strdup="unknown"
  tst_proto_strdup="unknown"
  tst_compi_strdup="unknown"
  tst_allow_strdup="unknown"
  #
  AC_MSG_CHECKING([if strdup can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([strdup])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_strdup="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_strdup="no"
  ])
  #
  if test "$tst_links_strdup" = "yes"; then
    AC_MSG_CHECKING([if strdup is prototyped])
    AC_EGREP_CPP([strdup],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_strdup="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_strdup="no"
    ])
  fi
  #
  if test "$tst_proto_strdup" = "yes"; then
    AC_MSG_CHECKING([if strdup is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != strdup(0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_strdup="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_strdup="no"
    ])
  fi
  #
  if test "$tst_compi_strdup" = "yes"; then
    AC_MSG_CHECKING([if strdup usage allowed])
    if test "x$curl_disallow_strdup" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_strdup="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_strdup="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if strdup might be used])
  if test "$tst_links_strdup" = "yes" &&
     test "$tst_proto_strdup" = "yes" &&
     test "$tst_compi_strdup" = "yes" &&
     test "$tst_allow_strdup" = "yes"; then
    AC_MSG_RESULT([yes])
    AC_DEFINE_UNQUOTED(HAVE_STRDUP, 1,
      [Define to 1 if you have the strdup function.])
    ac_cv_func_strdup="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_strdup="no"
  fi
])


dnl CURL_CHECK_FUNC_STRERROR_R
dnl -------------------------------------------------
dnl Verify if strerror_r is available, prototyped, can be compiled and
dnl seems to work. If all of these are true, and usage has not been
dnl previously disallowed with shell variable curl_disallow_strerror_r,
dnl then HAVE_STRERROR_R and STRERROR_R_TYPE_ARG3 will be defined, as
dnl well as one of HAVE_GLIBC_STRERROR_R or HAVE_POSIX_STRERROR_R.
dnl
dnl glibc-style strerror_r:
dnl
dnl      char *strerror_r(int errnum, char *workbuf, size_t bufsize);
dnl
dnl  glibc-style strerror_r returns a pointer to the the error string,
dnl  and might use the provided workbuf as a scratch area if needed. A
dnl  quick test on a few systems shows that it's usually not used at all.
dnl
dnl POSIX-style strerror_r:
dnl
dnl      int strerror_r(int errnum, char *resultbuf, size_t bufsize);
dnl
dnl  POSIX-style strerror_r returns 0 upon successful completion and the
dnl  error string in the provided resultbuf.
dnl

AC_DEFUN([CURL_CHECK_FUNC_STRERROR_R], [
  AC_REQUIRE([CURL_INCLUDES_STDLIB])dnl
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_strerror_r="unknown"
  tst_proto_strerror_r="unknown"
  tst_compi_strerror_r="unknown"
  tst_glibc_strerror_r="unknown"
  tst_posix_strerror_r="unknown"
  tst_allow_strerror_r="unknown"
  tst_works_glibc_strerror_r="unknown"
  tst_works_posix_strerror_r="unknown"
  tst_glibc_strerror_r_type_arg3="unknown"
  tst_posix_strerror_r_type_arg3="unknown"
  #
  AC_MSG_CHECKING([if strerror_r can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([strerror_r])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_strerror_r="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_strerror_r="no"
  ])
  #
  if test "$tst_links_strerror_r" = "yes"; then
    AC_MSG_CHECKING([if strerror_r is prototyped])
    AC_EGREP_CPP([strerror_r],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_strerror_r="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_strerror_r="no"
    ])
  fi
  #
  if test "$tst_proto_strerror_r" = "yes"; then
    AC_MSG_CHECKING([if strerror_r is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != strerror_r(0, 0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_strerror_r="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_strerror_r="no"
    ])
  fi
  #
  if test "$tst_compi_strerror_r" = "yes"; then
    AC_MSG_CHECKING([if strerror_r is glibc like])
    tst_glibc_strerror_r_type_arg3="unknown"
    for arg3 in 'size_t' 'int' 'unsigned int'; do
      if test "$tst_glibc_strerror_r_type_arg3" = "unknown"; then
        AC_COMPILE_IFELSE([
          AC_LANG_PROGRAM([[
            $curl_includes_string
          ]],[[
            char *strerror_r(int errnum, char *workbuf, $arg3 bufsize);
            if(0 != strerror_r(0, 0, 0))
              return 1;
          ]])
        ],[
          tst_glibc_strerror_r_type_arg3="$arg3"
        ])
      fi
    done
    case "$tst_glibc_strerror_r_type_arg3" in
      unknown)
        AC_MSG_RESULT([no])
        tst_glibc_strerror_r="no"
        ;;
      *)
        AC_MSG_RESULT([yes])
        tst_glibc_strerror_r="yes"
        ;;
    esac
  fi
  #
  dnl only do runtime verification when not cross-compiling
  if test "x$cross_compiling" != "xyes" &&
    test "$tst_glibc_strerror_r" = "yes"; then
    AC_MSG_CHECKING([if strerror_r seems to work])
    AC_RUN_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_stdlib
        $curl_includes_string
#       include <errno.h>
      ]],[[
        char buffer[1024];
        char *string = 0;
        buffer[0] = '\0';
        string = strerror_r(EACCES, buffer, sizeof(buffer));
        if(!string)
          exit(1); /* fail */
        if(!string[0])
          exit(1); /* fail */
        else
          exit(0);
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_works_glibc_strerror_r="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_works_glibc_strerror_r="no"
    ])
  fi
  #
  if test "$tst_compi_strerror_r" = "yes" &&
    test "$tst_works_glibc_strerror_r" != "yes"; then
    AC_MSG_CHECKING([if strerror_r is POSIX like])
    tst_posix_strerror_r_type_arg3="unknown"
    for arg3 in 'size_t' 'int' 'unsigned int'; do
      if test "$tst_posix_strerror_r_type_arg3" = "unknown"; then
        AC_COMPILE_IFELSE([
          AC_LANG_PROGRAM([[
            $curl_includes_string
          ]],[[
            int strerror_r(int errnum, char *resultbuf, $arg3 bufsize);
            if(0 != strerror_r(0, 0, 0))
              return 1;
          ]])
        ],[
          tst_posix_strerror_r_type_arg3="$arg3"
        ])
      fi
    done
    case "$tst_posix_strerror_r_type_arg3" in
      unknown)
        AC_MSG_RESULT([no])
        tst_posix_strerror_r="no"
        ;;
      *)
        AC_MSG_RESULT([yes])
        tst_posix_strerror_r="yes"
        ;;
    esac
  fi
  #
  dnl only do runtime verification when not cross-compiling
  if test "x$cross_compiling" != "xyes" &&
    test "$tst_posix_strerror_r" = "yes"; then
    AC_MSG_CHECKING([if strerror_r seems to work])
    AC_RUN_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_stdlib
        $curl_includes_string
#       include <errno.h>
      ]],[[
        char buffer[1024];
        int error = 1;
        buffer[0] = '\0';
        error = strerror_r(EACCES, buffer, sizeof(buffer));
        if(error)
          exit(1); /* fail */
        if(buffer[0] == '\0')
          exit(1); /* fail */
        else
          exit(0);
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_works_posix_strerror_r="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_works_posix_strerror_r="no"
    ])
  fi
  #
  if test "$tst_works_glibc_strerror_r" = "yes"; then
    tst_posix_strerror_r="no"
  fi
  if test "$tst_works_posix_strerror_r" = "yes"; then
    tst_glibc_strerror_r="no"
  fi
  if test "$tst_glibc_strerror_r" = "yes" &&
    test "$tst_works_glibc_strerror_r" != "no" &&
    test "$tst_posix_strerror_r" != "yes"; then
    tst_allow_strerror_r="check"
  fi
  if test "$tst_posix_strerror_r" = "yes" &&
    test "$tst_works_posix_strerror_r" != "no" &&
    test "$tst_glibc_strerror_r" != "yes"; then
    tst_allow_strerror_r="check"
  fi
  if test "$tst_allow_strerror_r" = "check"; then
    AC_MSG_CHECKING([if strerror_r usage allowed])
    if test "x$curl_disallow_strerror_r" != "xyes"; then
      AC_MSG_RESULT([yes])
      tst_allow_strerror_r="yes"
    else
      AC_MSG_RESULT([no])
      tst_allow_strerror_r="no"
    fi
  fi
  #
  AC_MSG_CHECKING([if strerror_r might be used])
  if test "$tst_links_strerror_r" = "yes" &&
     test "$tst_proto_strerror_r" = "yes" &&
     test "$tst_compi_strerror_r" = "yes" &&
     test "$tst_allow_strerror_r" = "yes"; then
    AC_MSG_RESULT([yes])
    if test "$tst_glibc_strerror_r" = "yes"; then
      AC_DEFINE_UNQUOTED(HAVE_STRERROR_R, 1,
        [Define to 1 if you have the strerror_r function.])
      AC_DEFINE_UNQUOTED(HAVE_GLIBC_STRERROR_R, 1,
        [Define to 1 if you have a working glibc-style strerror_r function.])
      AC_DEFINE_UNQUOTED(STRERROR_R_TYPE_ARG3, $tst_glibc_strerror_r_type_arg3,
        [Define to the type of arg 3 for strerror_r.])
    fi
    if test "$tst_posix_strerror_r" = "yes"; then
      AC_DEFINE_UNQUOTED(HAVE_STRERROR_R, 1,
        [Define to 1 if you have the strerror_r function.])
      AC_DEFINE_UNQUOTED(HAVE_POSIX_STRERROR_R, 1,
        [Define to 1 if you have a working POSIX-style strerror_r function.])
      AC_DEFINE_UNQUOTED(STRERROR_R_TYPE_ARG3, $tst_posix_strerror_r_type_arg3,
        [Define to the type of arg 3 for strerror_r.])
    fi
    ac_cv_func_strerror_r="yes"
  else
    AC_MSG_RESULT([no])
    ac_cv_func_strerror_r="no"
  fi
  #
  if test "$tst_compi_strerror_r" = "yes" &&
     test "$tst_allow_strerror_r" = "unknown"; then
    AC_MSG_WARN([cannot determine strerror_r() style: edit lib/curl_config.h manually.])
  fi
  #
])


dnl CURL_CHECK_FUNC_STRICMP
dnl -------------------------------------------------
dnl Verify if stricmp is available, prototyped, and
dnl can be compiled. If all of these are true, and
dnl usage has not been previously disallowed with
dnl shell variable curl_disallow_stricmp, then
dnl HAVE_STRICMP will be defined.

AC_DEFUN([CURL_CHECK_FUNC_STRICMP], [
  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
  #
  tst_links_stricmp="unknown"
  tst_proto_stricmp="unknown"
  tst_compi_stricmp="unknown"
  tst_allow_stricmp="unknown"
  #
  AC_MSG_CHECKING([if stricmp can be linked])
  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([stricmp])
  ],[
    AC_MSG_RESULT([yes])
    tst_links_stricmp="yes"
  ],[
    AC_MSG_RESULT([no])
    tst_links_stricmp="no"
  ])
  #
  if test "$tst_links_stricmp" = "yes"; then
    AC_MSG_CHECKING([if stricmp is prototyped])
    AC_EGREP_CPP([stricmp],[
      $curl_includes_string
    ],[
      AC_MSG_RESULT([yes])
      tst_proto_stricmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_proto_stricmp="no"
    ])
  fi
  #
  if test "$tst_proto_stricmp" = "yes"; then
    AC_MSG_CHECKING([if stricmp is compilable])
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
        $curl_includes_string
      ]],[[
        if(0 != stricmp(0, 0))
          return 1;
      ]])
    ],[
      AC_MSG_RESULT([yes])
      tst_compi_stricmp="yes"
    ],[
      AC_MSG_RESULT([no])
      tst_compi_stricmp="no"
    ])
  fi