diff --git a/gl/gettime.c b/gl/gettime.c
new file mode 100644
index 00000000..0a642dd2
--- /dev/null
+++ b/gl/gettime.c
@@ -0,0 +1,48 @@
+/* gettime -- get the system clock
+
+   Copyright (C) 2002, 2004-2007, 2009-2013 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#include <config.h>
+
+#include "timespec.h"
+
+#include <sys/time.h>
+
+/* Get the system time into *TS.  */
+
+void
+gettime (struct timespec *ts)
+{
+#if HAVE_NANOTIME
+  nanotime (ts);
+#else
+
+# if defined CLOCK_REALTIME && HAVE_CLOCK_GETTIME
+  if (clock_gettime (CLOCK_REALTIME, ts) == 0)
+    return;
+# endif
+
+  {
+    struct timeval tv;
+    gettimeofday (&tv, NULL);
+    ts->tv_sec = tv.tv_sec;
+    ts->tv_nsec = tv.tv_usec * 1000;
+  }
+
+#endif
+}
diff --git a/gl/gettimeofday.c b/gl/gettimeofday.c
new file mode 100644
index 00000000..ad65c6da
--- /dev/null
+++ b/gl/gettimeofday.c
@@ -0,0 +1,154 @@
+/* Provide gettimeofday for systems that don't have it or for which it's broken.
+
+   Copyright (C) 2001-2003, 2005-2007, 2009-2013 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 3, 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, see <http://www.gnu.org/licenses/>.  */
+
+/* written by Jim Meyering */
+
+#include <config.h>
+
+/* Specification.  */
+#include <sys/time.h>
+
+#include <time.h>
+
+#if HAVE_SYS_TIMEB_H
+# include <sys/timeb.h>
+#endif
+
+#if GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME
+
+/* Work around the bug in some systems whereby gettimeofday clobbers
+   the static buffer that localtime uses for its return value.  The
+   gettimeofday function from Mac OS X 10.0.4 (i.e., Darwin 1.3.7) has
+   this problem.  The tzset replacement is necessary for at least
+   Solaris 2.5, 2.5.1, and 2.6.  */
+
+static struct tm tm_zero_buffer;
+static struct tm *localtime_buffer_addr = &tm_zero_buffer;
+
+# undef localtime
+extern struct tm *localtime (time_t const *);
+
+# undef gmtime
+extern struct tm *gmtime (time_t const *);
+
+/* This is a wrapper for localtime.  It is used only on systems for which
+   gettimeofday clobbers the static buffer used for localtime's result.
+
+   On the first call, record the address of the static buffer that
+   localtime uses for its result.  */
+
+struct tm *
+rpl_localtime (time_t const *timep)
+{
+  struct tm *tm = localtime (timep);
+
+  if (localtime_buffer_addr == &tm_zero_buffer)
+    localtime_buffer_addr = tm;
+
+  return tm;
+}
+
+/* Same as above, since gmtime and localtime use the same buffer.  */
+struct tm *
+rpl_gmtime (time_t const *timep)
+{
+  struct tm *tm = gmtime (timep);
+
+  if (localtime_buffer_addr == &tm_zero_buffer)
+    localtime_buffer_addr = tm;
+
+  return tm;
+}
+
+#endif /* GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME */
+
+#if TZSET_CLOBBERS_LOCALTIME
+
+# undef tzset
+extern void tzset (void);
+
+/* This is a wrapper for tzset, for systems on which tzset may clobber
+   the static buffer used for localtime's result.  */
+void
+rpl_tzset (void)
+{
+  /* Save and restore the contents of the buffer used for localtime's
+     result around the call to tzset.  */
+  struct tm save = *localtime_buffer_addr;
+  tzset ();
+  *localtime_buffer_addr = save;
+}
+#endif
+
+/* This is a wrapper for gettimeofday.  It is used only on systems
+   that lack this function, or whose implementation of this function
+   causes problems.  */
+
+int
+gettimeofday (struct timeval *restrict tv, void *restrict tz)
+{
+#undef gettimeofday
+#if HAVE_GETTIMEOFDAY
+# if GETTIMEOFDAY_CLOBBERS_LOCALTIME
+  /* Save and restore the contents of the buffer used for localtime's
+     result around the call to gettimeofday.  */
+  struct tm save = *localtime_buffer_addr;
+# endif
+
+# if defined timeval /* 'struct timeval' overridden by gnulib?  */
+#  undef timeval
+  struct timeval otv;
+  int result = gettimeofday (&otv, (struct timezone *) tz);
+  if (result == 0)
+    {
+      tv->tv_sec = otv.tv_sec;
+      tv->tv_usec = otv.tv_usec;
+    }
+# else
+  int result = gettimeofday (tv, (struct timezone *) tz);
+# endif
+
+# if GETTIMEOFDAY_CLOBBERS_LOCALTIME
+  *localtime_buffer_addr = save;
+# endif
+
+  return result;
+
+#else
+
+# if HAVE__FTIME
+
+  struct _timeb timebuf;
+  _ftime (&timebuf);
+  tv->tv_sec = timebuf.time;
+  tv->tv_usec = timebuf.millitm * 1000;
+
+# else
+
+#  if !defined OK_TO_USE_1S_CLOCK
+#   error "Only 1-second nominal clock resolution found.  Is that intended?" \
+          "If so, compile with the -DOK_TO_USE_1S_CLOCK option."
+#  endif
+  tv->tv_sec = time (NULL);
+  tv->tv_usec = 0;
+
+# endif
+
+  return 0;
+
+#endif
+}
diff --git a/gl/m4/clock_time.m4 b/gl/m4/clock_time.m4
new file mode 100644
index 00000000..6597fb63
--- /dev/null
+++ b/gl/m4/clock_time.m4
@@ -0,0 +1,31 @@
+# clock_time.m4 serial 10
+dnl Copyright (C) 2002-2006, 2009-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# Check for clock_gettime and clock_settime, and set LIB_CLOCK_GETTIME.
+# For a program named, say foo, you should add a line like the following
+# in the corresponding Makefile.am file:
+# foo_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME)
+
+AC_DEFUN([gl_CLOCK_TIME],
+[
+  dnl Persuade glibc and Solaris <time.h> to declare these functions.
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+  # Solaris 2.5.1 needs -lposix4 to get the clock_gettime function.
+  # Solaris 7 prefers the library name -lrt to the obsolescent name -lposix4.
+
+  # Save and restore LIBS so e.g., -lrt, isn't added to it.  Otherwise, *all*
+  # programs in the package would end up linked with that potentially-shared
+  # library, inducing unnecessary run-time overhead.
+  LIB_CLOCK_GETTIME=
+  AC_SUBST([LIB_CLOCK_GETTIME])
+  gl_saved_libs=$LIBS
+    AC_SEARCH_LIBS([clock_gettime], [rt posix4],
+                   [test "$ac_cv_search_clock_gettime" = "none required" ||
+                    LIB_CLOCK_GETTIME=$ac_cv_search_clock_gettime])
+    AC_CHECK_FUNCS([clock_gettime clock_settime])
+  LIBS=$gl_saved_libs
+])
diff --git a/gl/m4/extern-inline.m4 b/gl/m4/extern-inline.m4
new file mode 100644
index 00000000..5880d4f4
--- /dev/null
+++ b/gl/m4/extern-inline.m4
@@ -0,0 +1,62 @@
+dnl 'extern inline' a la ISO C99.
+
+dnl Copyright 2012-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_EXTERN_INLINE],
+[
+  AH_VERBATIM([extern_inline],
+[/* _GL_INLINE is a portable alternative to ISO C99 plain 'inline'.
+   _GL_EXTERN_INLINE is a portable alternative to 'extern inline'.
+   _GL_INLINE_HEADER_BEGIN contains useful stuff to put
+     in an include file, before uses of _GL_INLINE.
+     It suppresses GCC's bogus "no previous prototype for 'FOO'" diagnostic,
+     when FOO is an inline function in the header; see
+     <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>.
+   _GL_INLINE_HEADER_END contains useful stuff to put
+     in the same include file, after uses of _GL_INLINE.
+
+   Suppress the use of extern inline on Apple's platforms,
+   as Libc-825.25 (2012-09-19) is incompatible with it; see
+   <http://lists.gnu.org/archive/html/bug-gnulib/2012-12/msg00023.html>.
+   Perhaps Apple will fix this some day.  */
+#if ((__GNUC__ \
+      ? defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__ \
+      : 199901L <= __STDC_VERSION__) \
+     && !defined __APPLE__)
+# define _GL_INLINE inline
+# define _GL_EXTERN_INLINE extern inline
+#elif 2 < __GNUC__ + (7 <= __GNUC_MINOR__) && !defined __APPLE__
+# if __GNUC_GNU_INLINE__
+   /* __gnu_inline__ suppresses a GCC 4.2 diagnostic.  */
+#  define _GL_INLINE extern inline __attribute__ ((__gnu_inline__))
+# else
+#  define _GL_INLINE extern inline
+# endif
+# define _GL_EXTERN_INLINE extern
+#else
+# define _GL_INLINE static _GL_UNUSED
+# define _GL_EXTERN_INLINE static _GL_UNUSED
+#endif
+
+#if 4 < __GNUC__ + (6 <= __GNUC_MINOR__)
+# if defined __GNUC_STDC_INLINE__ && __GNUC_STDC_INLINE__
+#  define _GL_INLINE_HEADER_CONST_PRAGMA
+# else
+#  define _GL_INLINE_HEADER_CONST_PRAGMA \
+     _Pragma ("GCC diagnostic ignored \"-Wsuggest-attribute=const\"")
+# endif
+# define _GL_INLINE_HEADER_BEGIN \
+    _Pragma ("GCC diagnostic push") \
+    _Pragma ("GCC diagnostic ignored \"-Wmissing-prototypes\"") \
+    _Pragma ("GCC diagnostic ignored \"-Wmissing-declarations\"") \
+    _GL_INLINE_HEADER_CONST_PRAGMA
+# define _GL_INLINE_HEADER_END \
+    _Pragma ("GCC diagnostic pop")
+#else
+# define _GL_INLINE_HEADER_BEGIN
+# define _GL_INLINE_HEADER_END
+#endif])
+])
diff --git a/gl/m4/gettime.m4 b/gl/m4/gettime.m4
new file mode 100644
index 00000000..dc100de5
--- /dev/null
+++ b/gl/m4/gettime.m4
@@ -0,0 +1,13 @@
+# gettime.m4 serial 8
+dnl Copyright (C) 2002, 2004-2006, 2009-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_GETTIME],
+[
+  dnl Prerequisites of lib/gettime.c.
+  AC_REQUIRE([gl_CLOCK_TIME])
+  AC_REQUIRE([gl_TIMESPEC])
+  AC_CHECK_FUNCS_ONCE([gettimeofday nanotime])
+])
diff --git a/gl/m4/gettimeofday.m4 b/gl/m4/gettimeofday.m4
new file mode 100644
index 00000000..3c05e59f
--- /dev/null
+++ b/gl/m4/gettimeofday.m4
@@ -0,0 +1,140 @@
+# serial 20
+
+# Copyright (C) 2001-2003, 2005, 2007, 2009-2013 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+dnl From Jim Meyering.
+
+AC_DEFUN([gl_FUNC_GETTIMEOFDAY],
+[
+  AC_REQUIRE([AC_C_RESTRICT])
+  AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+  AC_REQUIRE([gl_HEADER_SYS_TIME_H_DEFAULTS])
+  AC_CHECK_FUNCS_ONCE([gettimeofday])
+
+  gl_gettimeofday_timezone=void
+  if test $ac_cv_func_gettimeofday != yes; then
+    HAVE_GETTIMEOFDAY=0
+  else
+    gl_FUNC_GETTIMEOFDAY_CLOBBER
+    AC_CACHE_CHECK([for gettimeofday with POSIX signature],
+      [gl_cv_func_gettimeofday_posix_signature],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <sys/time.h>
+              struct timeval c;
+              int gettimeofday (struct timeval *restrict, void *restrict);
+            ]],
+            [[/* glibc uses struct timezone * rather than the POSIX void *
+                 if _GNU_SOURCE is defined.  However, since the only portable
+                 use of gettimeofday uses NULL as the second parameter, and
+                 since the glibc definition is actually more typesafe, it is
+                 not worth wrapping this to get a compliant signature.  */
+              int (*f) (struct timeval *restrict, void *restrict)
+                = gettimeofday;
+              int x = f (&c, 0);
+              return !(x | c.tv_sec | c.tv_usec);
+            ]])],
+          [gl_cv_func_gettimeofday_posix_signature=yes],
+          [AC_COMPILE_IFELSE(
+            [AC_LANG_PROGRAM(
+              [[#include <sys/time.h>
+int gettimeofday (struct timeval *restrict, struct timezone *restrict);
+              ]])],
+            [gl_cv_func_gettimeofday_posix_signature=almost],
+            [gl_cv_func_gettimeofday_posix_signature=no])])])
+    if test $gl_cv_func_gettimeofday_posix_signature = almost; then
+      gl_gettimeofday_timezone='struct timezone'
+    elif test $gl_cv_func_gettimeofday_posix_signature != yes; then
+      REPLACE_GETTIMEOFDAY=1
+    fi
+    dnl If we override 'struct timeval', we also have to override gettimeofday.
+    if test $REPLACE_STRUCT_TIMEVAL = 1; then
+      REPLACE_GETTIMEOFDAY=1
+    fi
+    m4_ifdef([gl_FUNC_TZSET_CLOBBER], [
+      gl_FUNC_TZSET_CLOBBER
+      case "$gl_cv_func_tzset_clobber" in
+        *yes)
+          REPLACE_GETTIMEOFDAY=1
+          gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+          AC_DEFINE([tzset], [rpl_tzset],
+            [Define to rpl_tzset if the wrapper function should be used.])
+          AC_DEFINE([TZSET_CLOBBERS_LOCALTIME], [1],
+            [Define if tzset clobbers localtime's static buffer.])
+          ;;
+      esac
+    ])
+  fi
+  AC_DEFINE_UNQUOTED([GETTIMEOFDAY_TIMEZONE], [$gl_gettimeofday_timezone],
+    [Define this to 'void' or 'struct timezone' to match the system's
+     declaration of the second argument to gettimeofday.])
+])
+
+
+dnl See if gettimeofday clobbers the static buffer that localtime uses
+dnl for its return value.  The gettimeofday function from Mac OS X 10.0.4
+dnl (i.e., Darwin 1.3.7) has this problem.
+dnl
+dnl If it does, then arrange to use gettimeofday and localtime only via
+dnl the wrapper functions that work around the problem.
+
+AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
+[
+ AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+ AC_CACHE_CHECK([whether gettimeofday clobbers localtime buffer],
+  [gl_cv_func_gettimeofday_clobber],
+  [AC_RUN_IFELSE(
+     [AC_LANG_PROGRAM(
+        [[#include <string.h>
+          #include <sys/time.h>
+          #include <time.h>
+          #include <stdlib.h>
+        ]],
+        [[
+          time_t t = 0;
+          struct tm *lt;
+          struct tm saved_lt;
+          struct timeval tv;
+          lt = localtime (&t);
+          saved_lt = *lt;
+          gettimeofday (&tv, NULL);
+          return memcmp (lt, &saved_lt, sizeof (struct tm)) != 0;
+        ]])],
+     [gl_cv_func_gettimeofday_clobber=no],
+     [gl_cv_func_gettimeofday_clobber=yes],
+     [# When cross-compiling:
+      case "$host_os" in
+                # Guess all is fine on glibc systems.
+        *-gnu*) gl_cv_func_gettimeofday_clobber="guessing no" ;;
+                # If we don't know, assume the worst.
+        *)      gl_cv_func_gettimeofday_clobber="guessing yes" ;;
+      esac
+     ])])
+
+ case "$gl_cv_func_gettimeofday_clobber" in
+   *yes)
+     REPLACE_GETTIMEOFDAY=1
+     gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+     AC_DEFINE([GETTIMEOFDAY_CLOBBERS_LOCALTIME], [1],
+       [Define if gettimeofday clobbers the localtime buffer.])
+     ;;
+ esac
+])
+
+AC_DEFUN([gl_GETTIMEOFDAY_REPLACE_LOCALTIME], [
+  AC_DEFINE([gmtime], [rpl_gmtime],
+    [Define to rpl_gmtime if the replacement function should be used.])
+  AC_DEFINE([localtime], [rpl_localtime],
+    [Define to rpl_localtime if the replacement function should be used.])
+])
+
+# Prerequisites of lib/gettimeofday.c.
+AC_DEFUN([gl_PREREQ_GETTIMEOFDAY], [
+  AC_CHECK_HEADERS([sys/timeb.h])
+  AC_CHECK_FUNCS([_ftime])
+])
diff --git a/gl/m4/sys_socket_h.m4 b/gl/m4/sys_socket_h.m4
new file mode 100644
index 00000000..94863776
--- /dev/null
+++ b/gl/m4/sys_socket_h.m4
@@ -0,0 +1,176 @@
+# sys_socket_h.m4 serial 23
+dnl Copyright (C) 2005-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Simon Josefsson.
+
+AC_DEFUN([gl_HEADER_SYS_SOCKET],
+[
+  AC_REQUIRE([gl_SYS_SOCKET_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST])
+
+  dnl On OSF/1, the functions recv(), send(), recvfrom(), sendto() have
+  dnl old-style declarations (with return type 'int' instead of 'ssize_t')
+  dnl unless _POSIX_PII_SOCKET is defined.
+  case "$host_os" in
+    osf*)
+      AC_DEFINE([_POSIX_PII_SOCKET], [1],
+        [Define to 1 in order to get the POSIX compatible declarations
+         of socket functions.])
+      ;;
+  esac
+
+  AC_CACHE_CHECK([whether <sys/socket.h> is self-contained],
+    [gl_cv_header_sys_socket_h_selfcontained],
+    [
+      AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/socket.h>]], [[]])],
+        [gl_cv_header_sys_socket_h_selfcontained=yes],
+        [gl_cv_header_sys_socket_h_selfcontained=no])
+    ])
+  if test $gl_cv_header_sys_socket_h_selfcontained = yes; then
+    dnl If the shutdown function exists, <sys/socket.h> should define
+    dnl SHUT_RD, SHUT_WR, SHUT_RDWR.
+    AC_CHECK_FUNCS([shutdown])
+    if test $ac_cv_func_shutdown = yes; then
+      AC_CACHE_CHECK([whether <sys/socket.h> defines the SHUT_* macros],
+        [gl_cv_header_sys_socket_h_shut],
+        [
+          AC_COMPILE_IFELSE(
+            [AC_LANG_PROGRAM([[#include <sys/socket.h>]],
+               [[int a[] = { SHUT_RD, SHUT_WR, SHUT_RDWR };]])],
+            [gl_cv_header_sys_socket_h_shut=yes],
+            [gl_cv_header_sys_socket_h_shut=no])
+        ])
+      if test $gl_cv_header_sys_socket_h_shut = no; then
+        SYS_SOCKET_H='sys/socket.h'
+      fi
+    fi
+  fi
+  # We need to check for ws2tcpip.h now.
+  gl_PREREQ_SYS_H_SOCKET
+  AC_CHECK_TYPES([struct sockaddr_storage, sa_family_t],,,[
+  /* sys/types.h is not needed according to POSIX, but the
+     sys/socket.h in i386-unknown-freebsd4.10 and
+     powerpc-apple-darwin5.5 required it. */
+#include <sys/types.h>
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#ifdef HAVE_WS2TCPIP_H
+#include <ws2tcpip.h>
+#endif
+])
+  if test $ac_cv_type_struct_sockaddr_storage = no; then
+    HAVE_STRUCT_SOCKADDR_STORAGE=0
+  fi
+  if test $ac_cv_type_sa_family_t = no; then
+    HAVE_SA_FAMILY_T=0
+  fi
+  if test $ac_cv_type_struct_sockaddr_storage != no; then
+    AC_CHECK_MEMBERS([struct sockaddr_storage.ss_family],
+      [],
+      [HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY=0],
+      [#include <sys/types.h>
+       #ifdef HAVE_SYS_SOCKET_H
+       #include <sys/socket.h>
+       #endif
+       #ifdef HAVE_WS2TCPIP_H
+       #include <ws2tcpip.h>
+       #endif
+      ])
+  fi
+  if test $HAVE_STRUCT_SOCKADDR_STORAGE = 0 || test $HAVE_SA_FAMILY_T = 0 \
+     || test $HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY = 0; then
+    SYS_SOCKET_H='sys/socket.h'
+  fi
+  gl_PREREQ_SYS_H_WINSOCK2
+
+  dnl Check for declarations of anything we want to poison if the
+  dnl corresponding gnulib module is not in use.
+  gl_WARN_ON_USE_PREPARE([[
+/* Some systems require prerequisite headers.  */
+#include <sys/types.h>
+#include <sys/socket.h>
+    ]], [socket connect accept bind getpeername getsockname getsockopt
+    listen recv send recvfrom sendto setsockopt shutdown accept4])
+])
+
+AC_DEFUN([gl_PREREQ_SYS_H_SOCKET],
+[
+  dnl Check prerequisites of the <sys/socket.h> replacement.
+  AC_REQUIRE([gl_CHECK_SOCKET_HEADERS])
+  gl_CHECK_NEXT_HEADERS([sys/socket.h])
+  if test $ac_cv_header_sys_socket_h = yes; then
+    HAVE_SYS_SOCKET_H=1
+    HAVE_WS2TCPIP_H=0
+  else
+    HAVE_SYS_SOCKET_H=0
+    if test $ac_cv_header_ws2tcpip_h = yes; then
+      HAVE_WS2TCPIP_H=1
+    else
+      HAVE_WS2TCPIP_H=0
+    fi
+  fi
+  AC_SUBST([HAVE_SYS_SOCKET_H])
+  AC_SUBST([HAVE_WS2TCPIP_H])
+])
+
+# Common prerequisites of the <sys/socket.h> replacement and of the
+# <sys/select.h> replacement.
+# Sets and substitutes HAVE_WINSOCK2_H.
+AC_DEFUN([gl_PREREQ_SYS_H_WINSOCK2],
+[
+  m4_ifdef([gl_UNISTD_H_DEFAULTS], [AC_REQUIRE([gl_UNISTD_H_DEFAULTS])])
+  m4_ifdef([gl_SYS_IOCTL_H_DEFAULTS], [AC_REQUIRE([gl_SYS_IOCTL_H_DEFAULTS])])
+  AC_CHECK_HEADERS_ONCE([sys/socket.h])
+  if test $ac_cv_header_sys_socket_h != yes; then
+    dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
+    dnl the check for those headers unconditional; yet cygwin reports
+    dnl that the headers are present but cannot be compiled (since on
+    dnl cygwin, all socket information should come from sys/socket.h).
+    AC_CHECK_HEADERS([winsock2.h])
+  fi
+  if test "$ac_cv_header_winsock2_h" = yes; then
+    HAVE_WINSOCK2_H=1
+    UNISTD_H_HAVE_WINSOCK2_H=1
+    SYS_IOCTL_H_HAVE_WINSOCK2_H=1
+  else
+    HAVE_WINSOCK2_H=0
+  fi
+  AC_SUBST([HAVE_WINSOCK2_H])
+])
+
+AC_DEFUN([gl_SYS_SOCKET_MODULE_INDICATOR],
+[
+  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+  AC_REQUIRE([gl_SYS_SOCKET_H_DEFAULTS])
+  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+  dnl Define it also as a C macro, for the benefit of the unit tests.
+  gl_MODULE_INDICATOR_FOR_TESTS([$1])
+])
+
+AC_DEFUN([gl_SYS_SOCKET_H_DEFAULTS],
+[
+  GNULIB_SOCKET=0;      AC_SUBST([GNULIB_SOCKET])
+  GNULIB_CONNECT=0;     AC_SUBST([GNULIB_CONNECT])
+  GNULIB_ACCEPT=0;      AC_SUBST([GNULIB_ACCEPT])
+  GNULIB_BIND=0;        AC_SUBST([GNULIB_BIND])
+  GNULIB_GETPEERNAME=0; AC_SUBST([GNULIB_GETPEERNAME])
+  GNULIB_GETSOCKNAME=0; AC_SUBST([GNULIB_GETSOCKNAME])
+  GNULIB_GETSOCKOPT=0;  AC_SUBST([GNULIB_GETSOCKOPT])
+  GNULIB_LISTEN=0;      AC_SUBST([GNULIB_LISTEN])
+  GNULIB_RECV=0;        AC_SUBST([GNULIB_RECV])
+  GNULIB_SEND=0;        AC_SUBST([GNULIB_SEND])
+  GNULIB_RECVFROM=0;    AC_SUBST([GNULIB_RECVFROM])
+  GNULIB_SENDTO=0;      AC_SUBST([GNULIB_SENDTO])
+  GNULIB_SETSOCKOPT=0;  AC_SUBST([GNULIB_SETSOCKOPT])
+  GNULIB_SHUTDOWN=0;    AC_SUBST([GNULIB_SHUTDOWN])
+  GNULIB_ACCEPT4=0;     AC_SUBST([GNULIB_ACCEPT4])
+  HAVE_STRUCT_SOCKADDR_STORAGE=1; AC_SUBST([HAVE_STRUCT_SOCKADDR_STORAGE])
+  HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY=1;
+                        AC_SUBST([HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY])
+  HAVE_SA_FAMILY_T=1;   AC_SUBST([HAVE_SA_FAMILY_T])
+  HAVE_ACCEPT4=1;       AC_SUBST([HAVE_ACCEPT4])
+])
diff --git a/gl/m4/sys_time_h.m4 b/gl/m4/sys_time_h.m4
new file mode 100644
index 00000000..0ac71ac5
--- /dev/null
+++ b/gl/m4/sys_time_h.m4
@@ -0,0 +1,110 @@
+# Configure a replacement for <sys/time.h>.
+# serial 8
+
+# Copyright (C) 2007, 2009-2013 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# Written by Paul Eggert and Martin Lambers.
+
+AC_DEFUN([gl_HEADER_SYS_TIME_H],
+[
+  dnl Use AC_REQUIRE here, so that the REPLACE_GETTIMEOFDAY=0 statement
+  dnl below is expanded once only, before all REPLACE_GETTIMEOFDAY=1
+  dnl statements that occur in other macros.
+  AC_REQUIRE([gl_HEADER_SYS_TIME_H_BODY])
+])
+
+AC_DEFUN([gl_HEADER_SYS_TIME_H_BODY],
+[
+  AC_REQUIRE([AC_C_RESTRICT])
+  AC_REQUIRE([gl_HEADER_SYS_TIME_H_DEFAULTS])
+  AC_CHECK_HEADERS_ONCE([sys/time.h])
+  gl_CHECK_NEXT_HEADERS([sys/time.h])
+
+  if test $ac_cv_header_sys_time_h != yes; then
+    HAVE_SYS_TIME_H=0
+  fi
+
+  dnl On native Windows with MSVC, 'struct timeval' is defined in <winsock2.h>
+  dnl only. So include that header in the list.
+  gl_PREREQ_SYS_H_WINSOCK2
+  AC_CACHE_CHECK([for struct timeval], [gl_cv_sys_struct_timeval],
+    [AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#if HAVE_SYS_TIME_H
+             #include <sys/time.h>
+            #endif
+            #include <time.h>
+            #if HAVE_WINSOCK2_H
+            # include <winsock2.h>
+            #endif
+          ]],
+          [[static struct timeval x; x.tv_sec = x.tv_usec;]])],
+       [gl_cv_sys_struct_timeval=yes],
+       [gl_cv_sys_struct_timeval=no])
+    ])
+  if test $gl_cv_sys_struct_timeval != yes; then
+    HAVE_STRUCT_TIMEVAL=0
+  else
+    dnl On native Windows with a 64-bit 'time_t', 'struct timeval' is defined
+    dnl (in <sys/time.h> and <winsock2.h> for mingw64, in <winsock2.h> only
+    dnl for MSVC) with a tv_sec field of type 'long' (32-bit!), which is
+    dnl smaller than the 'time_t' type mandated by POSIX.
+    dnl On OpenBSD 5.1 amd64, tv_sec is 64 bits and time_t 32 bits, but
+    dnl that is good enough.
+    AC_CACHE_CHECK([for wide-enough struct timeval.tv_sec member],
+      [gl_cv_sys_struct_timeval_tv_sec],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#if HAVE_SYS_TIME_H
+               #include <sys/time.h>
+              #endif
+              #include <time.h>
+              #if HAVE_WINSOCK2_H
+              # include <winsock2.h>
+              #endif
+            ]],
+            [[static struct timeval x;
+              typedef int verify_tv_sec_type[
+                sizeof (time_t) <= sizeof x.tv_sec ? 1 : -1
+              ];
+            ]])],
+         [gl_cv_sys_struct_timeval_tv_sec=yes],
+         [gl_cv_sys_struct_timeval_tv_sec=no])
+      ])
+    if test $gl_cv_sys_struct_timeval_tv_sec != yes; then
+      REPLACE_STRUCT_TIMEVAL=1
+    fi
+  fi
+
+  dnl Check for declarations of anything we want to poison if the
+  dnl corresponding gnulib module is not in use.
+  gl_WARN_ON_USE_PREPARE([[
+#if HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#include <time.h>
+    ]], [gettimeofday])
+])
+
+AC_DEFUN([gl_SYS_TIME_MODULE_INDICATOR],
+[
+  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+  AC_REQUIRE([gl_HEADER_SYS_TIME_H_DEFAULTS])
+  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+  dnl Define it also as a C macro, for the benefit of the unit tests.
+  gl_MODULE_INDICATOR_FOR_TESTS([$1])
+])
+
+AC_DEFUN([gl_HEADER_SYS_TIME_H_DEFAULTS],
+[
+  GNULIB_GETTIMEOFDAY=0;     AC_SUBST([GNULIB_GETTIMEOFDAY])
+  dnl Assume POSIX behavior unless another module says otherwise.
+  HAVE_GETTIMEOFDAY=1;       AC_SUBST([HAVE_GETTIMEOFDAY])
+  HAVE_STRUCT_TIMEVAL=1;     AC_SUBST([HAVE_STRUCT_TIMEVAL])
+  HAVE_SYS_TIME_H=1;         AC_SUBST([HAVE_SYS_TIME_H])
+  REPLACE_GETTIMEOFDAY=0;    AC_SUBST([REPLACE_GETTIMEOFDAY])
+  REPLACE_STRUCT_TIMEVAL=0;  AC_SUBST([REPLACE_STRUCT_TIMEVAL])
+])
diff --git a/gl/m4/time_h.m4 b/gl/m4/time_h.m4
new file mode 100644
index 00000000..3b839005
--- /dev/null
+++ b/gl/m4/time_h.m4
@@ -0,0 +1,109 @@
+# Configure a more-standard replacement for <time.h>.
+
+# Copyright (C) 2000-2001, 2003-2007, 2009-2013 Free Software Foundation, Inc.
+
+# serial 7
+
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# Written by Paul Eggert and Jim Meyering.
+
+AC_DEFUN([gl_HEADER_TIME_H],
+[
+  dnl Use AC_REQUIRE here, so that the default behavior below is expanded
+  dnl once only, before all statements that occur in other macros.
+  AC_REQUIRE([gl_HEADER_TIME_H_BODY])
+])
+
+AC_DEFUN([gl_HEADER_TIME_H_BODY],
+[
+  AC_REQUIRE([AC_C_RESTRICT])
+  AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS])
+  gl_NEXT_HEADERS([time.h])
+  AC_REQUIRE([gl_CHECK_TYPE_STRUCT_TIMESPEC])
+])
+
+dnl Check whether 'struct timespec' is declared
+dnl in time.h, sys/time.h, or pthread.h.
+
+AC_DEFUN([gl_CHECK_TYPE_STRUCT_TIMESPEC],
+[
+  AC_CHECK_HEADERS_ONCE([sys/time.h])
+  AC_CACHE_CHECK([for struct timespec in <time.h>],
+    [gl_cv_sys_struct_timespec_in_time_h],
+    [AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <time.h>
+          ]],
+          [[static struct timespec x; x.tv_sec = x.tv_nsec;]])],
+       [gl_cv_sys_struct_timespec_in_time_h=yes],
+       [gl_cv_sys_struct_timespec_in_time_h=no])])
+
+  TIME_H_DEFINES_STRUCT_TIMESPEC=0
+  SYS_TIME_H_DEFINES_STRUCT_TIMESPEC=0
+  PTHREAD_H_DEFINES_STRUCT_TIMESPEC=0
+  if test $gl_cv_sys_struct_timespec_in_time_h = yes; then
+    TIME_H_DEFINES_STRUCT_TIMESPEC=1
+  else
+    AC_CACHE_CHECK([for struct timespec in <sys/time.h>],
+      [gl_cv_sys_struct_timespec_in_sys_time_h],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <sys/time.h>
+            ]],
+            [[static struct timespec x; x.tv_sec = x.tv_nsec;]])],
+         [gl_cv_sys_struct_timespec_in_sys_time_h=yes],
+         [gl_cv_sys_struct_timespec_in_sys_time_h=no])])
+    if test $gl_cv_sys_struct_timespec_in_sys_time_h = yes; then
+      SYS_TIME_H_DEFINES_STRUCT_TIMESPEC=1
+    else
+      AC_CACHE_CHECK([for struct timespec in <pthread.h>],
+        [gl_cv_sys_struct_timespec_in_pthread_h],
+        [AC_COMPILE_IFELSE(
+           [AC_LANG_PROGRAM(
+              [[#include <pthread.h>
+              ]],
+              [[static struct timespec x; x.tv_sec = x.tv_nsec;]])],
+           [gl_cv_sys_struct_timespec_in_pthread_h=yes],
+           [gl_cv_sys_struct_timespec_in_pthread_h=no])])
+      if test $gl_cv_sys_struct_timespec_in_pthread_h = yes; then
+        PTHREAD_H_DEFINES_STRUCT_TIMESPEC=1
+      fi
+    fi
+  fi
+  AC_SUBST([TIME_H_DEFINES_STRUCT_TIMESPEC])
+  AC_SUBST([SYS_TIME_H_DEFINES_STRUCT_TIMESPEC])
+  AC_SUBST([PTHREAD_H_DEFINES_STRUCT_TIMESPEC])
+])
+
+AC_DEFUN([gl_TIME_MODULE_INDICATOR],
+[
+  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+  AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS])
+  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+  dnl Define it also as a C macro, for the benefit of the unit tests.
+  gl_MODULE_INDICATOR_FOR_TESTS([$1])
+])
+
+AC_DEFUN([gl_HEADER_TIME_H_DEFAULTS],
+[
+  GNULIB_MKTIME=0;                       AC_SUBST([GNULIB_MKTIME])
+  GNULIB_NANOSLEEP=0;                    AC_SUBST([GNULIB_NANOSLEEP])
+  GNULIB_STRPTIME=0;                     AC_SUBST([GNULIB_STRPTIME])
+  GNULIB_TIMEGM=0;                       AC_SUBST([GNULIB_TIMEGM])
+  GNULIB_TIME_R=0;                       AC_SUBST([GNULIB_TIME_R])
+  dnl Assume proper GNU behavior unless another module says otherwise.
+  HAVE_DECL_LOCALTIME_R=1;               AC_SUBST([HAVE_DECL_LOCALTIME_R])
+  HAVE_NANOSLEEP=1;                      AC_SUBST([HAVE_NANOSLEEP])
+  HAVE_STRPTIME=1;                       AC_SUBST([HAVE_STRPTIME])
+  HAVE_TIMEGM=1;                         AC_SUBST([HAVE_TIMEGM])
+  dnl If another module says to replace or to not replace, do that.
+  dnl Otherwise, replace only if someone compiles with -DGNULIB_PORTCHECK;
+  dnl this lets maintainers check for portability.
+  REPLACE_LOCALTIME_R=GNULIB_PORTCHECK;  AC_SUBST([REPLACE_LOCALTIME_R])
+  REPLACE_MKTIME=GNULIB_PORTCHECK;       AC_SUBST([REPLACE_MKTIME])
+  REPLACE_NANOSLEEP=GNULIB_PORTCHECK;    AC_SUBST([REPLACE_NANOSLEEP])
+  REPLACE_TIMEGM=GNULIB_PORTCHECK;       AC_SUBST([REPLACE_TIMEGM])
+])
diff --git a/gl/m4/timespec.m4 b/gl/m4/timespec.m4
new file mode 100644
index 00000000..399404b5
--- /dev/null
+++ b/gl/m4/timespec.m4
@@ -0,0 +1,11 @@
+#serial 15
+
+# Copyright (C) 2000-2001, 2003-2007, 2009-2013 Free Software Foundation, Inc.
+
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+dnl From Jim Meyering
+
+AC_DEFUN([gl_TIMESPEC], [:])
diff --git a/gl/sys_time.in.h b/gl/sys_time.in.h
new file mode 100644
index 00000000..1b7736be
--- /dev/null
+++ b/gl/sys_time.in.h
@@ -0,0 +1,205 @@
+/* Provide a more complete sys/time.h.
+
+   Copyright (C) 2007-2013 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 3, 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, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#if __GNUC__ >= 3
+@PRAGMA_SYSTEM_HEADER@
+#endif
+@PRAGMA_COLUMNS@
+
+#if defined _@GUARD_PREFIX@_SYS_TIME_H
+
+/* Simply delegate to the system's header, without adding anything.  */
+# if @HAVE_SYS_TIME_H@
+#  @INCLUDE_NEXT@ @NEXT_SYS_TIME_H@
+# endif
+
+#else
+
+# define _@GUARD_PREFIX@_SYS_TIME_H
+
+# if @HAVE_SYS_TIME_H@
+#  @INCLUDE_NEXT@ @NEXT_SYS_TIME_H@
+# else
+#  include <time.h>
+# endif
+
+/* On native Windows with MSVC, get the 'struct timeval' type.
+   Also, on native Windows with a 64-bit time_t, where we are overriding the
+   'struct timeval' type, get all declarations of system functions whose
+   signature contains 'struct timeval'.  */
+# if (defined _MSC_VER || @REPLACE_STRUCT_TIMEVAL@) && @HAVE_WINSOCK2_H@ && !defined _GL_INCLUDING_WINSOCK2_H
+#  define _GL_INCLUDING_WINSOCK2_H
+#  include <winsock2.h>
+#  undef _GL_INCLUDING_WINSOCK2_H
+# endif
+
+/* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
+
+/* The definition of _GL_ARG_NONNULL is copied here.  */
+
+/* The definition of _GL_WARN_ON_USE is copied here.  */
+
+# ifdef __cplusplus
+extern "C" {
+# endif
+
+# if !@HAVE_STRUCT_TIMEVAL@ || @REPLACE_STRUCT_TIMEVAL@
+
+#  if @REPLACE_STRUCT_TIMEVAL@
+#   define timeval rpl_timeval
+#  endif
+
+#  if !GNULIB_defined_struct_timeval
+struct timeval
+{
+  time_t tv_sec;
+  long int tv_usec;
+};
+#   define GNULIB_defined_struct_timeval 1
+#  endif
+
+# endif
+
+# ifdef __cplusplus
+}
+# endif
+
+# if @GNULIB_GETTIMEOFDAY@
+#  if @REPLACE_GETTIMEOFDAY@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef gettimeofday
+#    define gettimeofday rpl_gettimeofday
+#   endif
+_GL_FUNCDECL_RPL (gettimeofday, int,
+                  (struct timeval *restrict, void *restrict)
+                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (gettimeofday, int,
+                  (struct timeval *restrict, void *restrict));
+#  else
+#   if !@HAVE_GETTIMEOFDAY@
+_GL_FUNCDECL_SYS (gettimeofday, int,
+                  (struct timeval *restrict, void *restrict)
+                  _GL_ARG_NONNULL ((1)));
+#   endif
+/* Need to cast, because on glibc systems, by default, the second argument is
+                                                  struct timezone *.  */
+_GL_CXXALIAS_SYS_CAST (gettimeofday, int,
+                       (struct timeval *restrict, void *restrict));
+#  endif
+_GL_CXXALIASWARN (gettimeofday);
+# elif defined GNULIB_POSIXCHECK
+#  undef gettimeofday
+#  if HAVE_RAW_DECL_GETTIMEOFDAY
+_GL_WARN_ON_USE (gettimeofday, "gettimeofday is unportable - "
+                 "use gnulib module gettimeofday for portability");
+#  endif
+# endif
+
+/* Hide some function declarations from <winsock2.h>.  */
+
+# if defined _MSC_VER && @HAVE_WINSOCK2_H@
+#  if !defined _@GUARD_PREFIX@_UNISTD_H
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef close
+#    define close close_used_without_including_unistd_h
+#   else
+     _GL_WARN_ON_USE (close,
+                      "close() used without including <unistd.h>");
+#   endif
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef gethostname
+#    define gethostname gethostname_used_without_including_unistd_h
+#   else
+     _GL_WARN_ON_USE (gethostname,
+                      "gethostname() used without including <unistd.h>");
+#   endif
+#  endif
+#  if !defined _@GUARD_PREFIX@_SYS_SOCKET_H
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef socket
+#    define socket              socket_used_without_including_sys_socket_h
+#    undef connect
+#    define connect             connect_used_without_including_sys_socket_h
+#    undef accept
+#    define accept              accept_used_without_including_sys_socket_h
+#    undef bind
+#    define bind                bind_used_without_including_sys_socket_h
+#    undef getpeername
+#    define getpeername         getpeername_used_without_including_sys_socket_h
+#    undef getsockname
+#    define getsockname         getsockname_used_without_including_sys_socket_h
+#    undef getsockopt
+#    define getsockopt          getsockopt_used_without_including_sys_socket_h
+#    undef listen
+#    define listen              listen_used_without_including_sys_socket_h
+#    undef recv
+#    define recv                recv_used_without_including_sys_socket_h
+#    undef send
+#    define send                send_used_without_including_sys_socket_h
+#    undef recvfrom
+#    define recvfrom            recvfrom_used_without_including_sys_socket_h
+#    undef sendto
+#    define sendto              sendto_used_without_including_sys_socket_h
+#    undef setsockopt
+#    define setsockopt          setsockopt_used_without_including_sys_socket_h
+#    undef shutdown
+#    define shutdown            shutdown_used_without_including_sys_socket_h
+#   else
+     _GL_WARN_ON_USE (socket,
+                      "socket() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (connect,
+                      "connect() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (accept,
+                      "accept() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (bind,
+                      "bind() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (getpeername,
+                      "getpeername() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (getsockname,
+                      "getsockname() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (getsockopt,
+                      "getsockopt() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (listen,
+                      "listen() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (recv,
+                      "recv() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (send,
+                      "send() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (recvfrom,
+                      "recvfrom() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (sendto,
+                      "sendto() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (setsockopt,
+                      "setsockopt() used without including <sys/socket.h>");
+     _GL_WARN_ON_USE (shutdown,
+                      "shutdown() used without including <sys/socket.h>");
+#   endif
+#  endif
+#  if !defined _@GUARD_PREFIX@_SYS_SELECT_H
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef select
+#    define select select_used_without_including_sys_select_h
+#   else
+     _GL_WARN_ON_USE (select,
+                      "select() used without including <sys/select.h>");
+#   endif
+#  endif
+# endif
+
+#endif /* _@GUARD_PREFIX@_SYS_TIME_H */
diff --git a/gl/time.in.h b/gl/time.in.h
new file mode 100644
index 00000000..8ced7947
--- /dev/null
+++ b/gl/time.in.h
@@ -0,0 +1,248 @@
+/* A more-standard <time.h>.
+
+   Copyright (C) 2007-2013 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 3, 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, see <http://www.gnu.org/licenses/>.  */
+
+#if __GNUC__ >= 3
+@PRAGMA_SYSTEM_HEADER@
+#endif
+@PRAGMA_COLUMNS@
+
+/* Don't get in the way of glibc when it includes time.h merely to
+   declare a few standard symbols, rather than to declare all the
+   symbols.  Also, Solaris 8 <time.h> eventually includes itself
+   recursively; if that is happening, just include the system <time.h>
+   without adding our own declarations.  */
+#if (defined __need_time_t || defined __need_clock_t \
+     || defined __need_timespec \
+     || defined _@GUARD_PREFIX@_TIME_H)
+
+# @INCLUDE_NEXT@ @NEXT_TIME_H@
+
+#else
+
+# define _@GUARD_PREFIX@_TIME_H
+
+# @INCLUDE_NEXT@ @NEXT_TIME_H@
+
+/* NetBSD 5.0 mis-defines NULL.  */
+# include <stddef.h>
+
+/* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
+
+/* The definition of _GL_ARG_NONNULL is copied here.  */
+
+/* The definition of _GL_WARN_ON_USE is copied here.  */
+
+/* Some systems don't define struct timespec (e.g., AIX 4.1, Ultrix 4.3).
+   Or they define it with the wrong member names or define it in <sys/time.h>
+   (e.g., FreeBSD circa 1997).  Stock Mingw does not define it, but the
+   pthreads-win32 library defines it in <pthread.h>.  */
+# if ! @TIME_H_DEFINES_STRUCT_TIMESPEC@
+#  if @SYS_TIME_H_DEFINES_STRUCT_TIMESPEC@
+#   include <sys/time.h>
+#  elif @PTHREAD_H_DEFINES_STRUCT_TIMESPEC@
+#   include <pthread.h>
+/* The pthreads-win32 <pthread.h> also defines a couple of broken macros.  */
+#   undef asctime_r
+#   undef ctime_r
+#   undef gmtime_r
+#   undef localtime_r
+#   undef rand_r
+#   undef strtok_r
+#  else
+
+#   ifdef __cplusplus
+extern "C" {
+#   endif
+
+#   if !GNULIB_defined_struct_timespec
+#    undef timespec
+#    define timespec rpl_timespec
+struct timespec
+{
+  time_t tv_sec;
+  long int tv_nsec;
+};
+#    define GNULIB_defined_struct_timespec 1
+#   endif
+
+#   ifdef __cplusplus
+}
+#   endif
+
+#  endif
+# endif
+
+# if !GNULIB_defined_struct_time_t_must_be_integral
+/* Per http://austingroupbugs.net/view.php?id=327, POSIX requires
+   time_t to be an integer type, even though C99 permits floating
+   point.  We don't know of any implementation that uses floating
+   point, and it is much easier to write code that doesn't have to
+   worry about that corner case, so we force the issue.  */
+struct __time_t_must_be_integral {
+  unsigned int __floating_time_t_unsupported : (time_t) 1;
+};
+#  define GNULIB_defined_struct_time_t_must_be_integral 1
+# endif
+
+/* Sleep for at least RQTP seconds unless interrupted,  If interrupted,
+   return -1 and store the remaining time into RMTP.  See
+   <http://www.opengroup.org/susv3xsh/nanosleep.html>.  */
+# if @GNULIB_NANOSLEEP@
+#  if @REPLACE_NANOSLEEP@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    define nanosleep rpl_nanosleep
+#   endif
+_GL_FUNCDECL_RPL (nanosleep, int,
+                  (struct timespec const *__rqtp, struct timespec *__rmtp)
+                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (nanosleep, int,
+                  (struct timespec const *__rqtp, struct timespec *__rmtp));
+#  else
+#   if ! @HAVE_NANOSLEEP@
+_GL_FUNCDECL_SYS (nanosleep, int,
+                  (struct timespec const *__rqtp, struct timespec *__rmtp)
+                  _GL_ARG_NONNULL ((1)));
+#   endif
+_GL_CXXALIAS_SYS (nanosleep, int,
+                  (struct timespec const *__rqtp, struct timespec *__rmtp));
+#  endif
+_GL_CXXALIASWARN (nanosleep);
+# endif
+
+/* Return the 'time_t' representation of TP and normalize TP.  */
+# if @GNULIB_MKTIME@
+#  if @REPLACE_MKTIME@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    define mktime rpl_mktime
+#   endif
+_GL_FUNCDECL_RPL (mktime, time_t, (struct tm *__tp) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mktime, time_t, (struct tm *__tp));
+#  else
+_GL_CXXALIAS_SYS (mktime, time_t, (struct tm *__tp));
+#  endif
+_GL_CXXALIASWARN (mktime);
+# endif
+
+/* Convert TIMER to RESULT, assuming local time and UTC respectively.  See
+   <http://www.opengroup.org/susv3xsh/localtime_r.html> and
+   <http://www.opengroup.org/susv3xsh/gmtime_r.html>.  */
+# if @GNULIB_TIME_R@
+#  if @REPLACE_LOCALTIME_R@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef localtime_r
+#    define localtime_r rpl_localtime_r
+#   endif
+_GL_FUNCDECL_RPL (localtime_r, struct tm *, (time_t const *restrict __timer,
+                                             struct tm *restrict __result)
+                                            _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (localtime_r, struct tm *, (time_t const *restrict __timer,
+                                             struct tm *restrict __result));
+#  else
+#   if ! @HAVE_DECL_LOCALTIME_R@
+_GL_FUNCDECL_SYS (localtime_r, struct tm *, (time_t const *restrict __timer,
+                                             struct tm *restrict __result)
+                                            _GL_ARG_NONNULL ((1, 2)));
+#   endif
+_GL_CXXALIAS_SYS (localtime_r, struct tm *, (time_t const *restrict __timer,
+                                             struct tm *restrict __result));
+#  endif
+#  if @HAVE_DECL_LOCALTIME_R@
+_GL_CXXALIASWARN (localtime_r);
+#  endif
+#  if @REPLACE_LOCALTIME_R@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef gmtime_r
+#    define gmtime_r rpl_gmtime_r
+#   endif
+_GL_FUNCDECL_RPL (gmtime_r, struct tm *, (time_t const *restrict __timer,
+                                          struct tm *restrict __result)
+                                         _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (gmtime_r, struct tm *, (time_t const *restrict __timer,
+                                          struct tm *restrict __result));
+#  else
+#   if ! @HAVE_DECL_LOCALTIME_R@
+_GL_FUNCDECL_SYS (gmtime_r, struct tm *, (time_t const *restrict __timer,
+                                          struct tm *restrict __result)
+                                         _GL_ARG_NONNULL ((1, 2)));
+#   endif
+_GL_CXXALIAS_SYS (gmtime_r, struct tm *, (time_t const *restrict __timer,
+                                          struct tm *restrict __result));
+#  endif
+#  if @HAVE_DECL_LOCALTIME_R@
+_GL_CXXALIASWARN (gmtime_r);
+#  endif
+# endif
+
+/* Parse BUF as a time stamp, assuming FORMAT specifies its layout, and store
+   the resulting broken-down time into TM.  See
+   <http://www.opengroup.org/susv3xsh/strptime.html>.  */
+# if @GNULIB_STRPTIME@
+#  if ! @HAVE_STRPTIME@
+_GL_FUNCDECL_SYS (strptime, char *, (char const *restrict __buf,
+                                     char const *restrict __format,
+                                     struct tm *restrict __tm)
+                                    _GL_ARG_NONNULL ((1, 2, 3)));
+#  endif
+_GL_CXXALIAS_SYS (strptime, char *, (char const *restrict __buf,
+                                     char const *restrict __format,
+                                     struct tm *restrict __tm));
+_GL_CXXALIASWARN (strptime);
+# endif
+
+/* Convert TM to a time_t value, assuming UTC.  */
+# if @GNULIB_TIMEGM@
+#  if @REPLACE_TIMEGM@
+#   if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#    undef timegm
+#    define timegm rpl_timegm
+#   endif
+_GL_FUNCDECL_RPL (timegm, time_t, (struct tm *__tm) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (timegm, time_t, (struct tm *__tm));
+#  else
+#   if ! @HAVE_TIMEGM@
+_GL_FUNCDECL_SYS (timegm, time_t, (struct tm *__tm) _GL_ARG_NONNULL ((1)));
+#   endif
+_GL_CXXALIAS_SYS (timegm, time_t, (struct tm *__tm));
+#  endif
+_GL_CXXALIASWARN (timegm);
+# endif
+
+/* Encourage applications to avoid unsafe functions that can overrun
+   buffers when given outlandish struct tm values.  Portable
+   applications should use strftime (or even sprintf) instead.  */
+# if defined GNULIB_POSIXCHECK
+#  undef asctime
+_GL_WARN_ON_USE (asctime, "asctime can overrun buffers in some cases - "
+                 "better use strftime (or even sprintf) instead");
+# endif
+# if defined GNULIB_POSIXCHECK
+#  undef asctime_r
+_GL_WARN_ON_USE (asctime, "asctime_r can overrun buffers in some cases - "
+                 "better use strftime (or even sprintf) instead");
+# endif
+# if defined GNULIB_POSIXCHECK
+#  undef ctime
+_GL_WARN_ON_USE (asctime, "ctime can overrun buffers in some cases - "
+                 "better use strftime (or even sprintf) instead");
+# endif
+# if defined GNULIB_POSIXCHECK
+#  undef ctime_r
+_GL_WARN_ON_USE (asctime, "ctime_r can overrun buffers in some cases - "
+                 "better use strftime (or even sprintf) instead");
+# endif
+
+#endif
diff --git a/gl/timespec.c b/gl/timespec.c
new file mode 100644
index 00000000..2b6098ed
--- /dev/null
+++ b/gl/timespec.c
@@ -0,0 +1,3 @@
+#include <config.h>
+#define _GL_TIMESPEC_INLINE _GL_EXTERN_INLINE
+#include "timespec.h"
diff --git a/gl/timespec.h b/gl/timespec.h
new file mode 100644
index 00000000..d665e6cc
--- /dev/null
+++ b/gl/timespec.h
@@ -0,0 +1,92 @@
+/* timespec -- System time interface
+
+   Copyright (C) 2000, 2002, 2004-2005, 2007, 2009-2013 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 3 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+#if ! defined TIMESPEC_H
+# define TIMESPEC_H
+
+# include <time.h>
+
+_GL_INLINE_HEADER_BEGIN
+#ifndef _GL_TIMESPEC_INLINE
+# define _GL_TIMESPEC_INLINE _GL_INLINE
+#endif
+
+/* Return negative, zero, positive if A < B, A == B, A > B, respectively.
+
+   For each time stamp T, this code assumes that either:
+
+     * T.tv_nsec is in the range 0..999999999; or
+     * T.tv_sec corresponds to a valid leap second on a host that supports
+       leap seconds, and T.tv_nsec is in the range 1000000000..1999999999; or
+     * T.tv_sec is the minimum time_t value and T.tv_nsec is -1; or
+       T.tv_sec is the maximum time_t value and T.tv_nsec is 2000000000.
+       This allows for special struct timespec values that are less or
+       greater than all possible valid time stamps.
+
+   In all these cases, it is safe to subtract two tv_nsec values and
+   convert the result to integer without worrying about overflow on
+   any platform of interest to the GNU project, since all such
+   platforms have 32-bit int or wider.
+
+   Replacing "(int) (a.tv_nsec - b.tv_nsec)" with something like
+   "a.tv_nsec < b.tv_nsec ? -1 : a.tv_nsec > b.tv_nsec" would cause
+   this function to work in some cases where the above assumption is
+   violated, but not in all cases (e.g., a.tv_sec==1, a.tv_nsec==-2,
+   b.tv_sec==0, b.tv_nsec==999999999) and is arguably not worth the
+   extra instructions.  Using a subtraction has the advantage of
+   detecting some invalid cases on platforms that detect integer
+   overflow.
+
+   The (int) cast avoids a gcc -Wconversion warning.  */
+
+_GL_TIMESPEC_INLINE int
+timespec_cmp (struct timespec a, struct timespec b)
+{
+  return (a.tv_sec < b.tv_sec ? -1
+          : a.tv_sec > b.tv_sec ? 1
+          : (int) (a.tv_nsec - b.tv_nsec));
+}
+
+/* Return -1, 0, 1, depending on the sign of A.  A.tv_nsec must be
+   nonnegative.  */
+_GL_TIMESPEC_INLINE int
+timespec_sign (struct timespec a)
+{
+  return a.tv_sec < 0 ? -1 : a.tv_sec || a.tv_nsec;
+}
+
+struct timespec timespec_add (struct timespec, struct timespec)
+  _GL_ATTRIBUTE_CONST;
+struct timespec timespec_sub (struct timespec, struct timespec)
+  _GL_ATTRIBUTE_CONST;
+struct timespec dtotimespec (double)
+  _GL_ATTRIBUTE_CONST;
+
+/* Return an approximation to A, of type 'double'.  */
+_GL_TIMESPEC_INLINE double
+timespectod (struct timespec a)
+{
+  return a.tv_sec + a.tv_nsec / 1e9;
+}
+
+void gettime (struct timespec *);
+int settime (struct timespec const *);
+
+_GL_INLINE_HEADER_END
+
+#endif