- fdpass hardening:
	   - limit cmsg->cmsg_len to controllen, as some buggy OSes
             allow buffer overruns otherwise.
           - do not leak fds on fdpass protocol failures.
           - close extra fd's sent by non-compliant sender.

2.0  Wed Aug  4 15:59:08 CEST 2021
	- change build system to cmake.
	- add pkg-config file.
	- ptytty::login no longer writes a utmp, wtmp and lastlog
	  record when utmpx is available.
	- ptytty::login now provides the time with microseconds in
	  utmpx, wtmpx and lastlogx records.

1.8  Thu Feb 25 21:17:12 CET 2016
	- fix m4 underquoting bug that prevented utmpx detection from
	  working on systems without the utmp.h header, such as
	  freebsd 9 and newer.
	- fix ptytty::get hang on AIX.
	- ptytty::get on Solaris no longer makes the tty controlling
	  when the calling process does not have a controlling
	  terminal. Bug introduced in ptytty-1.4.

1.7  Thu Mar 19 22:04:33 CET 2015
	- fix various bugs that prevented the lib from working correctly on
	  some systems when using the helper process.
	- fix compilation on solaris with g++ >= 4.7.
	- fix compilation on freebsd/openbsd.
	- nuke the pid check when !PTYTTY_REENTRANT: it breaks urxvtd, and
          serves little purpose as it is off in normal builds anyway.
	- add ecb.h.

1.6  Sat Jan 21 16:59:22 CET 2012
	- fix compilation on solaris.
	- remove dependency on STL.

1.5  Thu Dec 22 23:32:08 CET 2011
	- INCOMPATIBLE CHANGE: ptytty::get no longer sets the pty fd
	  non-blocking.
	- the login_shell argument of ptytty::login is now properly
	  honoured.
	- ptytty::get no longer makes the pty a controlling terminal
	  when using posix_openpt.
	- remove support for utmpx ut_session extension, it serves no
	  purpose.
	- remove support for writing lastlog when the lastlog file is a
	  directory, no system is known to require this code.
	- do not clear ut_user in utmpx logout records because
	  pututxline fails otherwise on solaris.
	- fix writing of bsd style utmp when the tty is closed before
	  calling ptytty::login.
	- fix compilation on systems with bsd style utmp and no utmpx,
	  such as openbsd.

1.4  Wed Jun 29 14:36:19 CEST 2011
	- push stream modules in ptytty::get rather than in
	  ptytty::make_controlling_tty. This makes tty ioctls (such as
	  TIOCSWINSZ, to set the window size) work even if
	  make_controlling_tty has not been called.
	- clear user and host fields in utmp(x) logout records.
	- fix utmpx detection on upcoming FreeBSD 9.
	- switch to automake.
	- refactoring and cleanup.

1.3  Sun May  3 23:44:16 CEST 2009
	- fedora 9 apparently has isastream but not the stropts.h header
          file for it, work around this (reported by Tuncer Ayaz).
        - detect if lastlog is a directory at runtime.
        - assume ttyslot availability for bsd style utmp.
        - make sure the alignment for fd passing control messages
          is correct and work around some NetBSD issues (Taylor R Campbell).
        - add some missing include statements.

1.2  Thu Aug  2 15:50:02 CEST 2007
        - restore the SysV way of acquiring a controlling terminal
          (for systems having no TIOCSCTTY such as cygwin or solaris).
        - when using openpty, get the slave name with ttyname.
        - fix invalid free when using _getpty.
        - update config.guess and config.sub.

1.1  Mon Feb 12 18:25:07 CET 2007
        - when using the helper, close the pty and tty fd also in the main
          process (patch by Andrei Paskevich).
        - implement ptytty::sanitise_stdfd to ensure stdin/out/error exist
          and are usable and use it.

1.0  Tue Oct  3 13:18:00 CEST 2006
        - do not call chmod/chown with 0 argument.
        - reformatted ptytty.C to hopefully be more clear.

0.2  Thu Jul 20 04:57:26 CEST 2006
        - move include files outside #ifdef PTYTTY_HELPER in proxy.C.
        - added proxy.C to cvs (was missing before).

0.1  Wed Jan 25 22:56:36 CET 2006
        - added the C API.
        - small freebsd patch to fdpass.C by Thierry Thomas.
        - added eg/c-sample.c.
        - small fixes to the C api.
        - restructured source files.
        - added set*uid checks to ptytty.m4.

0.0
        - originally cloned from rxvt-unicode.