legal

一个开放源代码的 AT&T 的 Korn Shell 的复制品, 支持大多数 ksh89 的特性。

pdksh is provided AS IS, with NO WARRANTY, either expressed or implied.

The vast majority of the code that makes pdksh is in the public domain.
The exceptions are:
	sigact.c and sigact.h
		These are covered by copyrighten by Simon J. Gerraty;
		the copyright notice for these files is as follows:
		    This is free software.  It comes with NO WARRANTY.
		    Permission to use, modify and distribute this source code
		    is granted subject to the following conditions.
		    1/ that that the above copyright notice and this notice 
		    are preserved in all copies and that due credit be given 
		    to the author.  
		    2/ that any changes to this code are clearly commented 
		    as such so that the author does get blamed for bugs 
		    other than his own.
	aclocal.m4
		This is covered by the GNU General Public Licence (GPL)
		as it contains modified versions of macros that come with
		GNU autoconf.  As this is used solely for configuration,
		the pdksh code itself is not covered by the GPL.
		The following is taken from autoconf 2.x documentation
		(info autoconf questions distributing) concerning use
		of autoconf in programs:

		   There are no restrictions on how the configuration
		   scripts that Autoconf produces may be distributed
		   or used.  In Autoconf version 1, they were covered by
		   the GNU General Public License.  We still encourage
		   software authors to distribute their work under terms
		   like those of the GPL, but doing so is not required
		   to use Autoconf.

That's it.  Short and simple.