acinclude.m4

  AC_LINK_IFELSE([
    AC_LANG_FUNC_LINK_TRY([getnameinfo])
  ],[
    AC_MSG_RESULT([yes])
    curl_cv_getnameinfo="yes"
  ],[
    AC_MSG_RESULT([no])
    curl_cv_getnameinfo="no"
  ])
  #
  if test "$curl_cv_getnameinfo" != "yes"; then
    AC_MSG_CHECKING([deeper for getnameinfo])
    AC_LINK_IFELSE([
      AC_LANG_PROGRAM([[
      ]],[[
        getnameinfo();
      ]])
    ],[
      AC_MSG_RESULT([yes])
      curl_cv_getnameinfo="yes"
    ],[
      AC_MSG_RESULT([but still no])
      curl_cv_getnameinfo="no"
    ])
  fi
  #
  if test "$curl_cv_getnameinfo" != "yes"; then
    AC_MSG_CHECKING([deeper and deeper for getnameinfo])
    AC_LINK_IFELSE([
      AC_LANG_PROGRAM([[
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#endif
      ]],[[
        getnameinfo(0, 0, 0, 0, 0, 0, 0);
      ]])
    ],[
      AC_MSG_RESULT([yes])
      curl_cv_getnameinfo="yes"
    ],[
      AC_MSG_RESULT([but still no])
      curl_cv_getnameinfo="no"
    ])
  fi
  #
  if test "$curl_cv_getnameinfo" = "yes"; then
    AC_CACHE_CHECK([types of arguments for getnameinfo],
      [curl_cv_func_getnameinfo_args], [
      curl_cv_func_getnameinfo_args="unknown"
      for gni_arg1 in 'struct sockaddr *' 'const struct sockaddr *' 'void *'; do
        for gni_arg2 in 'socklen_t' 'size_t' 'int'; do
          for gni_arg46 in 'size_t' 'int' 'socklen_t' 'unsigned int' 'DWORD'; do
            for gni_arg7 in 'int' 'unsigned int'; do
              if test "$curl_cv_func_getnameinfo_args" = "unknown"; then
                AC_COMPILE_IFELSE([
                  AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#if (!defined(_WIN32_WINNT)) || (_WIN32_WINNT < 0x0501)
#undef _WIN32_WINNT
#define _WIN32_WINNT 0x0501
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h> 
#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
#endif
#define GNICALLCONV WSAAPI
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#define GNICALLCONV
#endif
                    extern int GNICALLCONV getnameinfo($gni_arg1, $gni_arg2,
                                           char *, $gni_arg46,
                                           char *, $gni_arg46,
                                           $gni_arg7);
                  ]],[[
                    $gni_arg2 salen=0;
                    $gni_arg46 hostlen=0;
                    $gni_arg46 servlen=0;
                    $gni_arg7 flags=0;
                    int res = getnameinfo(0, salen, 0, hostlen, 0, servlen, flags);
                  ]])
                ],[
                  curl_cv_func_getnameinfo_args="$gni_arg1,$gni_arg2,$gni_arg46,$gni_arg7"
                ])
              fi
            done
          done
        done
      done
    ]) # AC-CACHE-CHECK
    if test "$curl_cv_func_getnameinfo_args" = "unknown"; then
      AC_MSG_WARN([Cannot find proper types to use for getnameinfo args])
      AC_MSG_WARN([HAVE_GETNAMEINFO will not be defined])
    else
      gni_prev_IFS=$IFS; IFS=','
      set dummy `echo "$curl_cv_func_getnameinfo_args" | sed 's/\*/\*/g'`
      IFS=$gni_prev_IFS
      shift
      #
      gni_qual_type_arg1=$[1]
      #
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG2, $[2],
        [Define to the type of arg 2 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG46, $[3],
        [Define to the type of args 4 and 6 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG7, $[4],
        [Define to the type of arg 7 for getnameinfo.])
      #
      prev_sh_opts=$-
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set -f
          ;;
      esac
      #
      case "$gni_qual_type_arg1" in
        const*)
          gni_qual_arg1=const
          gni_type_arg1=`echo $gni_qual_type_arg1 | sed 's/^const //'`
        ;;
        *)
          gni_qual_arg1=
          gni_type_arg1=$gni_qual_type_arg1
        ;;
      esac
      #
      AC_DEFINE_UNQUOTED(GETNAMEINFO_QUAL_ARG1, $gni_qual_arg1,
        [Define to the type qualifier of arg 1 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG1, $gni_type_arg1,
        [Define to the type of arg 1 for getnameinfo.])
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set +f
          ;;
      esac
      #
      AC_DEFINE_UNQUOTED(HAVE_GETNAMEINFO, 1,
        [Define to 1 if you have the getnameinfo function.])
      ac_cv_func_getnameinfo="yes"
    fi
  fi
])


dnl TYPE_SOCKADDR_STORAGE
dnl -------------------------------------------------
dnl Check for struct sockaddr_storage. Most IPv6-enabled 
dnl hosts have it, but AIX 4.3 is one known exception.

AC_DEFUN([TYPE_SOCKADDR_STORAGE],
[
   AC_CHECK_TYPE([struct sockaddr_storage],
        AC_DEFINE(HAVE_STRUCT_SOCKADDR_STORAGE, 1,
                  [if struct sockaddr_storage is defined]), ,
   [
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#endif
   ])
])


dnl CURL_CHECK_NI_WITHSCOPEID
dnl -------------------------------------------------
dnl Check for working NI_WITHSCOPEID in getnameinfo()

AC_DEFUN([CURL_CHECK_NI_WITHSCOPEID], [
  AC_REQUIRE([CURL_CHECK_FUNC_GETNAMEINFO])dnl
  AC_REQUIRE([TYPE_SOCKADDR_STORAGE])dnl
  AC_CHECK_HEADERS(stdio.h sys/types.h sys/socket.h \
                   netdb.h netinet/in.h arpa/inet.h)
  #
  AC_CACHE_CHECK([for working NI_WITHSCOPEID], 
    [ac_cv_working_ni_withscopeid], [
    AC_RUN_IFELSE([
      AC_LANG_PROGRAM([[
#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
      ]],[[
#if defined(NI_WITHSCOPEID) && defined(HAVE_GETNAMEINFO)
#ifdef HAVE_STRUCT_SOCKADDR_STORAGE
        struct sockaddr_storage sa;
#else
        unsigned char sa[256];
#endif
        char hostbuf[NI_MAXHOST];
        int rc;
        GETNAMEINFO_TYPE_ARG2 salen = (GETNAMEINFO_TYPE_ARG2)sizeof(sa);
        GETNAMEINFO_TYPE_ARG46 hostlen = (GETNAMEINFO_TYPE_ARG46)sizeof(hostbuf);
        GETNAMEINFO_TYPE_ARG7 flags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
        int fd = socket(AF_INET6, SOCK_STREAM, 0);
        if(fd < 0) {
          perror("socket()");
          return 1; /* Error creating socket */
        }
        rc = getsockname(fd, (GETNAMEINFO_TYPE_ARG1)&sa, &salen);
        if(rc) {
          perror("getsockname()");
          return 2; /* Error retrieving socket name */
        }
        rc = getnameinfo((GETNAMEINFO_TYPE_ARG1)&sa, salen, hostbuf, hostlen, NULL, 0, flags);
        if(rc) {
          printf("rc = %s\n", gai_strerror(rc));
          return 3; /* Error translating socket address */
        }
        return 0; /* Ok, NI_WITHSCOPEID works */
#else
        return 4; /* Error, NI_WITHSCOPEID not defined or no getnameinfo() */
#endif
      ]]) # AC-LANG-PROGRAM
    ],[
      # Exit code == 0. Program worked.
      ac_cv_working_ni_withscopeid="yes"
    ],[
      # Exit code != 0. Program failed.
      ac_cv_working_ni_withscopeid="no"
    ],[
      # Program is not run when cross-compiling. So we assume
      # NI_WITHSCOPEID will work if we are able to compile it.
      AC_COMPILE_IFELSE([
        AC_LANG_PROGRAM([[
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
        ]],[[
          unsigned int dummy= NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
        ]])
      ],[
        ac_cv_working_ni_withscopeid="yes"
      ],[
        ac_cv_working_ni_withscopeid="no"
      ]) # AC-COMPILE-IFELSE
    ]) # AC-RUN-IFELSE
  ]) # AC-CACHE-CHECK
  case "$ac_cv_working_ni_withscopeid" in
    yes)
      AC_DEFINE(HAVE_NI_WITHSCOPEID, 1,
        [Define to 1 if NI_WITHSCOPEID exists and works.])
      ;;
  esac
])


dnl CURL_CHECK_FUNC_RECV
dnl -------------------------------------------------
dnl Test if the socket recv() function is available, 
dnl and check its return type and the types of its 
dnl arguments. If the function succeeds HAVE_RECV 
dnl will be defined, defining the types of the arguments 
dnl in RECV_TYPE_ARG1, RECV_TYPE_ARG2, RECV_TYPE_ARG3 
dnl and RECV_TYPE_ARG4, defining the type of the function
dnl return value in RECV_TYPE_RETV.

AC_DEFUN([CURL_CHECK_FUNC_RECV], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK])dnl
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK2])dnl
  AC_CHECK_HEADERS(sys/types.h sys/socket.h)
  #
  AC_MSG_CHECKING([for recv])
  AC_LINK_IFELSE([
    AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
    ]],[[
      recv(0, 0, 0, 0);
    ]])
  ],[
    AC_MSG_RESULT([yes])
    curl_cv_recv="yes"
  ],[
    AC_MSG_RESULT([no])
    curl_cv_recv="no"
  ])
  #
  if test "$curl_cv_recv" = "yes"; then
    AC_CACHE_CHECK([types of args and return type for recv],
      [curl_cv_func_recv_args], [
      curl_cv_func_recv_args="unknown"
      for recv_retv in 'int' 'ssize_t'; do
        for recv_arg1 in 'int' 'ssize_t' 'SOCKET'; do
          for recv_arg2 in 'char *' 'void *'; do
            for recv_arg3 in 'size_t' 'int' 'socklen_t' 'unsigned int'; do
              for recv_arg4 in 'int' 'unsigned int'; do
                if test "$curl_cv_func_recv_args" = "unknown"; then
                  AC_COMPILE_IFELSE([
                    AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#define RECVCALLCONV PASCAL
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#define RECVCALLCONV
#endif
                      extern $recv_retv RECVCALLCONV
                      recv($recv_arg1, $recv_arg2, $recv_arg3, $recv_arg4);
                    ]],[[
                      $recv_arg1 s=0;
                      $recv_arg2 buf=0;
                      $recv_arg3 len=0;
                      $recv_arg4 flags=0;
                      $recv_retv res = recv(s, buf, len, flags);
                    ]])
                  ],[
                    curl_cv_func_recv_args="$recv_arg1,$recv_arg2,$recv_arg3,$recv_arg4,$recv_retv"
                  ])
                fi
              done
            done
          done
        done
      done
    ]) # AC-CACHE-CHECK
    if test "$curl_cv_func_recv_args" = "unknown"; then
      AC_MSG_ERROR([Cannot find proper types to use for recv args])
    else
      recv_prev_IFS=$IFS; IFS=','
      set dummy `echo "$curl_cv_func_recv_args" | sed 's/\*/\*/g'`
      IFS=$recv_prev_IFS
      shift
      #
      AC_DEFINE_UNQUOTED(RECV_TYPE_ARG1, $[1],
        [Define to the type of arg 1 for recv.])
      AC_DEFINE_UNQUOTED(RECV_TYPE_ARG2, $[2],
        [Define to the type of arg 2 for recv.])
      AC_DEFINE_UNQUOTED(RECV_TYPE_ARG3, $[3],
        [Define to the type of arg 3 for recv.])
      AC_DEFINE_UNQUOTED(RECV_TYPE_ARG4, $[4],
        [Define to the type of arg 4 for recv.])
      AC_DEFINE_UNQUOTED(RECV_TYPE_RETV, $[5],
        [Define to the function return type for recv.])
      #
      AC_DEFINE_UNQUOTED(HAVE_RECV, 1,
        [Define to 1 if you have the recv function.])
      ac_cv_func_recv="yes"
    fi
  else
    AC_MSG_ERROR([Unable to link function recv])
  fi
])


dnl CURL_CHECK_FUNC_SEND
dnl -------------------------------------------------
dnl Test if the socket send() function is available, 
dnl and check its return type and the types of its 
dnl arguments. If the function succeeds HAVE_SEND 
dnl will be defined, defining the types of the arguments 
dnl in SEND_TYPE_ARG1, SEND_TYPE_ARG2, SEND_TYPE_ARG3 
dnl and SEND_TYPE_ARG4, defining the type of the function
dnl return value in SEND_TYPE_RETV, and also defining the 
dnl type qualifier of second argument in SEND_QUAL_ARG2.

AC_DEFUN([CURL_CHECK_FUNC_SEND], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK])dnl
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK2])dnl
  AC_CHECK_HEADERS(sys/types.h sys/socket.h)
  #
  AC_MSG_CHECKING([for send])
  AC_LINK_IFELSE([
    AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
    ]],[[
      send(0, 0, 0, 0);
    ]])
  ],[
    AC_MSG_RESULT([yes])
    curl_cv_send="yes"
  ],[
    AC_MSG_RESULT([no])
    curl_cv_send="no"
  ])
  #
  if test "$curl_cv_send" = "yes"; then
    AC_CACHE_CHECK([types of args and return type for send],
      [curl_cv_func_send_args], [
      curl_cv_func_send_args="unknown"
      for send_retv in 'int' 'ssize_t'; do
        for send_arg1 in 'int' 'ssize_t' 'SOCKET'; do
          for send_arg2 in 'char *' 'void *' 'const char *' 'const void *'; do
            for send_arg3 in 'size_t' 'int' 'socklen_t' 'unsigned int'; do
              for send_arg4 in 'int' 'unsigned int'; do
                if test "$curl_cv_func_send_args" = "unknown"; then
                  AC_COMPILE_IFELSE([
                    AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#define SENDCALLCONV PASCAL
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#define SENDCALLCONV
#endif
                      extern $send_retv SENDCALLCONV
                      send($send_arg1, $send_arg2, $send_arg3, $send_arg4);
                    ]],[[
                      $send_arg1 s=0;
                      $send_arg3 len=0;
                      $send_arg4 flags=0;
                      $send_retv res = send(s, 0, len, flags);
                    ]])
                  ],[
                    curl_cv_func_send_args="$send_arg1,$send_arg2,$send_arg3,$send_arg4,$send_retv"
                  ])
                fi
              done
            done
          done
        done
      done
    ]) # AC-CACHE-CHECK
    if test "$curl_cv_func_send_args" = "unknown"; then
      AC_MSG_ERROR([Cannot find proper types to use for send args])
    else
      send_prev_IFS=$IFS; IFS=','
      set dummy `echo "$curl_cv_func_send_args" | sed 's/\*/\*/g'`
      IFS=$send_prev_IFS
      shift
      #
      send_qual_type_arg2=$[2]
      #
      AC_DEFINE_UNQUOTED(SEND_TYPE_ARG1, $[1],
        [Define to the type of arg 1 for send.])
      AC_DEFINE_UNQUOTED(SEND_TYPE_ARG3, $[3],
        [Define to the type of arg 3 for send.])
      AC_DEFINE_UNQUOTED(SEND_TYPE_ARG4, $[4],
        [Define to the type of arg 4 for send.])
      AC_DEFINE_UNQUOTED(SEND_TYPE_RETV, $[5],
        [Define to the function return type for send.])
      #
      prev_sh_opts=$-
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set -f
          ;;
      esac
      #
      case "$send_qual_type_arg2" in
        const*)
          send_qual_arg2=const
          send_type_arg2=`echo $send_qual_type_arg2 | sed 's/^const //'`
        ;;
        *)
          send_qual_arg2=
          send_type_arg2=$send_qual_type_arg2
        ;;
      esac
      #
      AC_DEFINE_UNQUOTED(SEND_QUAL_ARG2, $send_qual_arg2,
        [Define to the type qualifier of arg 2 for send.])
      AC_DEFINE_UNQUOTED(SEND_TYPE_ARG2, $send_type_arg2,
        [Define to the type of arg 2 for send.])
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set +f
          ;;
      esac
      #
      AC_DEFINE_UNQUOTED(HAVE_SEND, 1,
        [Define to 1 if you have the send function.])
      ac_cv_func_send="yes"
    fi
  else
    AC_MSG_ERROR([Unable to link function send])
  fi
])


dnl CURL_CHECK_FUNC_RECVFROM
dnl -------------------------------------------------
dnl Test if the socket recvfrom() function is available,
dnl and check its return type and the types of its
dnl arguments. If the function succeeds HAVE_RECVFROM
dnl will be defined, defining the types of the arguments
dnl in RECVFROM_TYPE_ARG1, RECVFROM_TYPE_ARG2, and so on
dnl to RECVFROM_TYPE_ARG6, defining also the type of the
dnl function return value in RECVFROM_TYPE_RETV.
dnl Notice that the types returned for pointer arguments
dnl will actually be the type pointed by the pointer.

AC_DEFUN([CURL_CHECK_FUNC_RECVFROM], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK])dnl
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK2])dnl
  AC_CHECK_HEADERS(sys/types.h sys/socket.h)
  #
  AC_MSG_CHECKING([for recvfrom])
  AC_LINK_IFELSE([
    AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
    ]],[[
      recvfrom(0, 0, 0, 0, 0, 0);
    ]])
  ],[
    AC_MSG_RESULT([yes])
    curl_cv_recvfrom="yes"
  ],[
    AC_MSG_RESULT([no])
    curl_cv_recvfrom="no"
  ])
  #
  if test "$curl_cv_recvfrom" = "yes"; then
    AC_CACHE_CHECK([types of args and return type for recvfrom],
      [curl_cv_func_recvfrom_args], [
      curl_cv_func_recvfrom_args="unknown"
      for recvfrom_retv in 'int' 'ssize_t'; do
        for recvfrom_arg1 in 'int' 'ssize_t' 'SOCKET'; do
          for recvfrom_arg2 in 'char *' 'void *'; do
            for recvfrom_arg3 in 'size_t' 'int' 'socklen_t' 'unsigned int'; do
              for recvfrom_arg4 in 'int' 'unsigned int'; do
                for recvfrom_arg5 in 'struct sockaddr *' 'void *'; do
                  for recvfrom_arg6 in 'socklen_t *' 'int *' 'unsigned int *' 'size_t *' 'void *'; do
                    if test "$curl_cv_func_recvfrom_args" = "unknown"; then
                      AC_COMPILE_IFELSE([
                        AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#define RECVFROMCALLCONV PASCAL
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#define RECVFROMCALLCONV
#endif
                          extern $recvfrom_retv RECVFROMCALLCONV
                          recvfrom($recvfrom_arg1, $recvfrom_arg2,
                                   $recvfrom_arg3, $recvfrom_arg4,
                                   $recvfrom_arg5, $recvfrom_arg6);
                        ]],[[
                          $recvfrom_arg1 s=0;
                          $recvfrom_arg2 buf=0;
                          $recvfrom_arg3 len=0;
                          $recvfrom_arg4 flags=0;
                          $recvfrom_arg5 addr=0;
                          $recvfrom_arg6 addrlen=0;
                          $recvfrom_retv res=0;
                          res = recvfrom(s, buf, len, flags, addr, addrlen);
                        ]])
                      ],[
                        curl_cv_func_recvfrom_args="$recvfrom_arg1,$recvfrom_arg2,$recvfrom_arg3,$recvfrom_arg4,$recvfrom_arg5,$recvfrom_arg6,$recvfrom_retv"
                      ])
                    fi
                  done
                done
              done
            done
          done
        done
      done
    ]) # AC-CACHE-CHECK
    if test "$curl_cv_func_recvfrom_args" = "unknown"; then
      AC_MSG_ERROR([Cannot find proper types to use for recvfrom args])
    else
      recvfrom_prev_IFS=$IFS; IFS=','
      set dummy `echo "$curl_cv_func_recvfrom_args" | sed 's/\*/\*/g'`
      IFS=$recvfrom_prev_IFS
      shift
      #
      recvfrom_ptrt_arg2=$[2]
      recvfrom_ptrt_arg5=$[5]
      recvfrom_ptrt_arg6=$[6]
      #
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG1, $[1],
        [Define to the type of arg 1 for recvfrom.])
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG3, $[3],
        [Define to the type of arg 3 for recvfrom.])
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG4, $[4],
        [Define to the type of arg 4 for recvfrom.])
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_RETV, $[7],
        [Define to the function return type for recvfrom.])
      #
      prev_sh_opts=$-
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set -f
          ;;
      esac
      #
      recvfrom_type_arg2=`echo $recvfrom_ptrt_arg2 | sed 's/ \*//'`
      recvfrom_type_arg5=`echo $recvfrom_ptrt_arg5 | sed 's/ \*//'`
      recvfrom_type_arg6=`echo $recvfrom_ptrt_arg6 | sed 's/ \*//'`
      #
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG2, $recvfrom_type_arg2,
        [Define to the type pointed by arg 2 for recvfrom.])
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG5, $recvfrom_type_arg5,
        [Define to the type pointed by arg 5 for recvfrom.])
      AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG6, $recvfrom_type_arg6,
        [Define to the type pointed by arg 6 for recvfrom.])
      #
      if test "$recvfrom_type_arg2" = "void"; then
        AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG2_IS_VOID, 1,
          [Define to 1 if the type pointed by arg 2 for recvfrom is void.])
      fi
      if test "$recvfrom_type_arg5" = "void"; then
        AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG5_IS_VOID, 1,
          [Define to 1 if the type pointed by arg 5 for recvfrom is void.])
      fi
      if test "$recvfrom_type_arg6" = "void"; then
        AC_DEFINE_UNQUOTED(RECVFROM_TYPE_ARG6_IS_VOID, 1,
          [Define to 1 if the type pointed by arg 6 for recvfrom is void.])
      fi
      #
      case $prev_sh_opts in
        *f*)
          ;;
        *)
          set +f
          ;;
      esac
      #
      AC_DEFINE_UNQUOTED(HAVE_RECVFROM, 1,
        [Define to 1 if you have the recvfrom function.])
      ac_cv_func_recvfrom="yes"
    fi
  else
    AC_MSG_ERROR([Unable to link function recvfrom])
  fi
])


dnl CURL_CHECK_MSG_NOSIGNAL
dnl -------------------------------------------------
dnl Check for MSG_NOSIGNAL

AC_DEFUN([CURL_CHECK_MSG_NOSIGNAL], [
  AC_CHECK_HEADERS(sys/types.h sys/socket.h)
  AC_CACHE_CHECK([for MSG_NOSIGNAL], [ac_cv_msg_nosignal], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
      ]],[[
        int flag=MSG_NOSIGNAL;
      ]])
    ],[
      ac_cv_msg_nosignal="yes"
    ],[
      ac_cv_msg_nosignal="no"
    ])
  ])
  case "$ac_cv_msg_nosignal" in
    yes)
      AC_DEFINE_UNQUOTED(HAVE_MSG_NOSIGNAL, 1,
        [Define to 1 if you have the MSG_NOSIGNAL flag.])
      ;;
  esac
])


dnl CURL_CHECK_STRUCT_TIMEVAL
dnl -------------------------------------------------
dnl Check for timeval struct

AC_DEFUN([CURL_CHECK_STRUCT_TIMEVAL], [
  AC_REQUIRE([AC_HEADER_TIME])dnl
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK])dnl
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK2])dnl
  AC_CHECK_HEADERS(sys/types.h sys/time.h time.h)
  AC_CACHE_CHECK([for struct timeval], [ac_cv_struct_timeval], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([[
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#ifdef TIME_WITH_SYS_TIME
#include <time.h>
#endif
#else
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#endif
      ]],[[
        struct timeval ts;
        ts.tv_sec  = 0;
        ts.tv_usec = 0;
      ]])
    ],[
      ac_cv_struct_timeval="yes"
    ],[
      ac_cv_struct_timeval="no"
    ])
  ])
  case "$ac_cv_struct_timeval" in
    yes)
      AC_DEFINE_UNQUOTED(HAVE_STRUCT_TIMEVAL, 1,
        [Define to 1 if you have the timeval struct.])
      ;;
  esac
])


dnl TYPE_SIG_ATOMIC_T
dnl -------------------------------------------------
dnl Check if the sig_atomic_t type is available, and
dnl verify if it is already defined as volatile.

AC_DEFUN([TYPE_SIG_ATOMIC_T], [
  AC_CHECK_HEADERS(signal.h)
  AC_CHECK_TYPE([sig_atomic_t],[
    AC_DEFINE(HAVE_SIG_ATOMIC_T, 1,
      [Define to 1 if sig_atomic_t is an available typedef.])
  ], ,[
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif
  ])
  case "$ac_cv_type_sig_atomic_t" in
    yes)
      #
      AC_MSG_CHECKING([if sig_atomic_t is already defined as volatile])
      AC_LINK_IFELSE([
        AC_LANG_PROGRAM([[
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif
        ]],[[
          static volatile sig_atomic_t dummy = 0;
        ]])
      ],[
        AC_MSG_RESULT([no])
        ac_cv_sig_atomic_t_volatile="no"
      ],[
        AC_MSG_RESULT([yes])
        ac_cv_sig_atomic_t_volatile="yes"
      ])
      #
      if test "$ac_cv_sig_atomic_t_volatile" = "yes"; then
        AC_DEFINE(HAVE_SIG_ATOMIC_T_VOLATILE, 1,
          [Define to 1 if sig_atomic_t is already defined as volatile.])
      fi
      ;;
  esac
])


dnl CURL_CHECK_NONBLOCKING_SOCKET
dnl -------------------------------------------------
dnl Check for how to set a socket to non-blocking state. There seems to exist
dnl four known different ways, with the one used almost everywhere being POSIX
dnl and XPG3, while the other different ways for different systems (old BSD,
dnl Windows and Amiga).
dnl
dnl There are two known platforms (AIX 3.x and SunOS 4.1.x) where the
dnl O_NONBLOCK define is found but does not work. This condition is attempted
dnl to get caught in this script by using an excessive number of #ifdefs...

AC_DEFUN([CURL_CHECK_NONBLOCKING_SOCKET], [
  AC_MSG_CHECKING([non-blocking sockets style])
  nonblock="unknown"
  #
  AC_COMPILE_IFELSE([
    AC_LANG_PROGRAM([[
/* headers for O_NONBLOCK test */
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
/* */
#if defined(sun) || defined(__sun__) || \
    defined(__SUNPRO_C) || defined(__SUNPRO_CC)
# if defined(__SVR4) || defined(__srv4__)
#  define PLATFORM_SOLARIS
# else
#  define PLATFORM_SUNOS4
# endif
#endif
#if (defined(_AIX) || defined(__xlC__)) && !defined(_AIX41)
# define PLATFORM_AIX_V3
#endif
/* */
#if defined(PLATFORM_SUNOS4) || defined(PLATFORM_AIX_V3) || defined(__BEOS__)
#error "O_NONBLOCK does not work on this platform"
#endif
    ]],[[
      /* O_NONBLOCK source test */
      int socket;
      int flags = fcntl(socket, F_SETFL, flags | O_NONBLOCK);