diff -Nru snapdev-1.1.38.0~lunar/debian/changelog snapdev-1.1.39.0~lunar/debian/changelog
--- snapdev-1.1.38.0~lunar/debian/changelog	2023-11-10 21:32:29.000000000 +0000
+++ snapdev-1.1.39.0~lunar/debian/changelog	2023-12-10 23:11:37.000000000 +0000
@@ -1,4 +1,12 @@
-snapdev (1.1.38.0~lunar) lunar; urgency=high
+snapdev (1.1.39.0~lunar) lunar; urgency=high
+
+  * Added min()/max() for timespec_ex.
+  * Extracted stream_fd.h from isatty.h.
+  * Added a function to detect whether a timestamp is in the future or not.
+
+ -- Alexis Wilke <alexis@m2osw.com>  Sun, 10 Dec 2023 15:11:37 -0800
+
+snapdev (1.1.38.0~jammy) jammy; urgency=high
 
   * Added another #include <cstdint>.
 
diff -Nru snapdev-1.1.38.0~lunar/snapdev/CMakeLists.txt snapdev-1.1.39.0~lunar/snapdev/CMakeLists.txt
--- snapdev-1.1.38.0~lunar/snapdev/CMakeLists.txt	2023-09-01 02:22:42.000000000 +0000
+++ snapdev-1.1.39.0~lunar/snapdev/CMakeLists.txt	2023-11-26 04:38:56.000000000 +0000
@@ -80,6 +80,7 @@
         safe_variable.h
         sizeof_bitfield.h
         static_to_dynamic_buffer.h
+        stream_fd.h
         stringize.h
         string_replace_many.h
         timespec_ex.h
diff -Nru snapdev-1.1.38.0~lunar/snapdev/isatty.h snapdev-1.1.39.0~lunar/snapdev/isatty.h
--- snapdev-1.1.38.0~lunar/snapdev/isatty.h	2023-02-25 21:33:35.000000000 +0000
+++ snapdev-1.1.39.0~lunar/snapdev/isatty.h	2023-11-26 04:36:12.000000000 +0000
@@ -17,12 +17,11 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #pragma once
 
-// C++
+// self
 //
-#include    <fstream>
-#include    <iostream>
-#include    <ext/stdio_filebuf.h>
-#include    <ext/stdio_sync_filebuf.h>
+#include    <snapdev/stream_fd.h>
+
+
 
 // C
 //
@@ -35,26 +34,6 @@
 
 
 
-namespace detail
-{
-
-template<typename _CharT
-       , typename _Traits = std::char_traits<_CharT>>
-class our_basic_filebuf
-    : public std::basic_filebuf<_CharT, _Traits>
-{
-public:
-    std::__c_file * file() throw()
-    {
-        //return std::basic_filebuf<_CharT, _Traits>::_M_file.file();
-        return this->_M_file.file();
-    }
-};
-
-} // namespace detail
-
-
-
 /** \brief Check whether a C++ iostream is a TTY.
  *
  * This function checks the specified stream and if it represents a TTY
@@ -77,50 +56,15 @@
  */
 template<typename _CharT
        , typename _Traits = std::char_traits<_CharT>>
-bool isatty(std::basic_ios<_CharT, _Traits> const & s)
+bool isatty(std::basic_ios<_CharT, _Traits> const & stream)
 {
-    // in most cases, we use cin, cout, cerr, or clog which are all
-    // stdio_sync_filebuf<> objects
-    {
-        typedef __gnu_cxx::stdio_sync_filebuf<_CharT, _Traits> io_sync_buffer_t;
-        io_sync_buffer_t * buffer(dynamic_cast<io_sync_buffer_t *>(s.rdbuf()));
-        if(buffer != nullptr)
-        {
-            return ::isatty(fileno(buffer->file()));
-        }
-    }
-
-    // in this case, we first do a dynamic_cast<>() to make sure we find the
-    // correct buffer; if present we can do a static_cast<>() to gain access
-    // to the _M_file field and thus the file() function (there is also an
-    // fd() function, but to be consistent with the other cases, I used a
-    // file() like function only)
-    {
-        typedef std::basic_filebuf<_CharT, _Traits> file_buffer_t;
-        file_buffer_t * file_buffer(dynamic_cast<file_buffer_t *>(s.rdbuf()));
-        if(file_buffer != nullptr)
-        {
-            typedef detail::our_basic_filebuf<_CharT, _Traits> hack_buffer_t;
-            hack_buffer_t * buffer(static_cast<hack_buffer_t *>(file_buffer));
-            if(buffer != nullptr)
-            {
-                return ::isatty(fileno(buffer->file()));
-            }
-        }
-    }
-
-    // older versions (C++98) used this class -- it is probably never
-    // going to be true so I put it last
+    int const r(stream_fd(stream));
+    if(r < 0)
     {
-        typedef __gnu_cxx::stdio_filebuf<_CharT, _Traits> io_buffer_t;
-        io_buffer_t * buffer(dynamic_cast<io_buffer_t *>(s.rdbuf()));
-        if(buffer != nullptr)
-        {
-            return ::isatty(fileno(buffer->file()));
-        }
+        return false;
     }
 
-    return false;
+    return ::isatty(r);
 }
 
 
diff -Nru snapdev-1.1.38.0~lunar/snapdev/stream_fd.h snapdev-1.1.39.0~lunar/snapdev/stream_fd.h
--- snapdev-1.1.38.0~lunar/snapdev/stream_fd.h	1970-01-01 00:00:00.000000000 +0000
+++ snapdev-1.1.39.0~lunar/snapdev/stream_fd.h	2023-11-26 04:35:37.000000000 +0000
@@ -0,0 +1,144 @@
+// Copyright (c) 2011-2023  Made to Order Software Corp.  All Rights Reserved
+//
+// https://snapwebsites.org/project/snapdev
+// contact@m2osw.com
+//
+// 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 <https://www.gnu.org/licenses/>.
+#pragma once
+
+// C++
+//
+//#include    <fstream>
+#include    <iostream>
+#include    <ext/stdio_filebuf.h>
+#include    <ext/stdio_sync_filebuf.h>
+
+// C
+//
+//#include    <unistd.h>
+
+
+
+namespace snapdev
+{
+
+
+
+namespace detail
+{
+
+template<typename _CharT
+       , typename _Traits = std::char_traits<_CharT>>
+class our_basic_filebuf
+    : public std::basic_filebuf<_CharT, _Traits>
+{
+public:
+    std::__c_file * file() throw()
+    {
+        //return std::basic_filebuf<_CharT, _Traits>::_M_file.file();
+        return this->_M_file.file();
+    }
+};
+
+} // namespace detail
+
+
+
+/** \brief Retrieve the FILE object of a C++ stream.
+ *
+ * This function attempts to retrieve a FILE object from a C++ stream.
+ * This assumes the stream is an fstream of some sort.
+ *
+ * \tparam _CharT  type of character this stream handles.
+ * \tparam _Traits  traits of the characters based on CharT by default.
+ * \param[in] stream  The stream to check.
+ *
+ * \return the stream file object or nullptr on failure.
+ */
+template<typename _CharT
+       , typename _Traits = std::char_traits<_CharT>>
+FILE * stream_file(std::basic_ios<_CharT, _Traits> const & stream)
+{
+    // in most cases, we use cin, cout, cerr, or clog which are all
+    // stdio_sync_filebuf<> objects
+    {
+        typedef __gnu_cxx::stdio_sync_filebuf<_CharT, _Traits> io_sync_buffer_t;
+        io_sync_buffer_t * buffer(dynamic_cast<io_sync_buffer_t *>(stream.rdbuf()));
+        if(buffer != nullptr)
+        {
+            return buffer->file();
+        }
+    }
+
+    // in this case, we first do a dynamic_cast<>() to make sure we find the
+    // correct buffer; if present we can do a static_cast<>() to gain access
+    // to the _M_file field and thus the file() function (there is also an
+    // fd() function, but to be consistent with the other cases, I used a
+    // file() like function only)
+    {
+        typedef std::basic_filebuf<_CharT, _Traits> file_buffer_t;
+        file_buffer_t * file_buffer(dynamic_cast<file_buffer_t *>(stream.rdbuf()));
+        if(file_buffer != nullptr)
+        {
+            typedef detail::our_basic_filebuf<_CharT, _Traits> hack_buffer_t;
+            hack_buffer_t * buffer(static_cast<hack_buffer_t *>(file_buffer));
+            if(buffer != nullptr)
+            {
+                return buffer->file();
+            }
+        }
+    }
+
+    // older versions (C++98) used this class -- it is probably never
+    // going to be true so I put it last
+    {
+        typedef __gnu_cxx::stdio_filebuf<_CharT, _Traits> io_buffer_t;
+        io_buffer_t * buffer(dynamic_cast<io_buffer_t *>(stream.rdbuf()));
+        if(buffer != nullptr)
+        {
+            return buffer->file();
+        }
+    }
+
+    return nullptr;
+}
+
+
+/** \brief Retrieve the file descriptor of a C++ stream.
+ *
+ * This function attempts to retrieve a file descriptor from a C++ stream.
+ * This assumes the stream is an fstream of some sort.
+ *
+ * \tparam _CharT  type of character this stream handles.
+ * \tparam _Traits  traits of the characters based on CharT by default.
+ * \param[in] stream  The stream to check.
+ *
+ * \return the stream file descriptor or -1 on failure.
+ */
+template<typename _CharT
+       , typename _Traits = std::char_traits<_CharT>>
+int stream_fd(std::basic_ios<_CharT, _Traits> const & stream)
+{
+    FILE * f(stream_file<_CharT, _Traits>(stream));
+    if(f == nullptr)
+    {
+        return -1;
+    }
+    return fileno(f);
+}
+
+
+
+} // namespace snapdev
+// vim: ts=4 sw=4 et
diff -Nru snapdev-1.1.38.0~lunar/snapdev/timespec_ex.h snapdev-1.1.39.0~lunar/snapdev/timespec_ex.h
--- snapdev-1.1.38.0~lunar/snapdev/timespec_ex.h	2023-11-06 04:48:03.000000000 +0000
+++ snapdev-1.1.39.0~lunar/snapdev/timespec_ex.h	2023-11-26 05:03:54.000000000 +0000
@@ -82,6 +82,10 @@
 DECLARE_EXCEPTION(timespec_ex_exception, overflow);
 
 
+class timespec_ex;
+inline timespec_ex now(clockid_t clk_id = CLOCK_REALTIME);
+
+
 class timespec_ex
     : public timespec
 {
@@ -1285,6 +1289,56 @@
     {
         return compare(t) >= 0;
     }
+
+
+    /** \brief Return the minimum possible timespec.
+     *
+     * This function returns a timespec with the smallest possible time.
+     *
+     * \return A timespec_ex with the minimum possible time.
+     */
+    static timespec_ex min()
+    {
+        return timespec_ex(std::numeric_limits<std::int64_t>::min(), 0);
+    }
+
+
+    /** \brief Return the maximum possible timespec.
+     *
+     * This function returns a timespec with the smallest possible time.
+     *
+     * \return A timespec_ex with the minimum possible time.
+     */
+    static timespec_ex max()
+    {
+        return timespec_ex(std::numeric_limits<std::int64_t>::max(), 999'999'999L);
+    }
+
+
+    /** \brief Check whether time is in the future.
+     *
+     * This function checks whether this timespec_ex represents a time in the
+     * future.
+     *
+     * You may pass an \p epsilon parameter to allow a gap between now and
+     * the time you consider in the future. By default, \p epsilon is set to
+     * zero. If you may pass a negative time in which case the threshold is
+     * moved in the past (i.e. a -5 second epsilon means this function returns
+     * true if "this >= now - 5 second").
+     *
+     * \note
+     * If this time is exactly equal to now(), then the function returns
+     * false (assuming an epsilon of 0).
+     *
+     * \param[in] epsilon  The allowed discrepancy, 0 by default.
+     *
+     * \return true if time is in the future.
+     */
+    bool is_in_the_future(snapdev::timespec_ex const & epsilon = { 0, 0 }) const
+    {
+        snapdev::timespec_ex const threshold(now() + epsilon);
+        return *this > threshold;
+    }
 };
 
 
@@ -1303,7 +1357,7 @@
  *
  * \return A timespec_ex object with "now" as the time.
  */
-inline timespec_ex now(clockid_t clk_id = CLOCK_REALTIME)
+inline timespec_ex now(clockid_t clk_id)
 {
     timespec_ex n;
     int const r(clock_gettime(clk_id, &n));