ReadMe for pd ksh .. Murphy's Law

[Brendan Kehoe]

  The result of the patches I posted will come up with perfectly
  compilable code .. but incorrect instructions. (I didn't
  triple-check it.) What follows is the right ReadMe. (Basically you
  have to do make link before you can do make in the stdc and posix
  directories.)

   The full patched & compilable source is also available on
   ftp.cs.widener.edu (192.55.239.132) in pub/unix/ksh.tar.Z.

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	Notes on the Standard C / POSIX P1003.1 package

  This package contains header files and library routines to provide a
standard C (ANSI) and POSIX enviroment for portable programs.  This
allows most OS dependcies to be removed from an application, making it
much more readable, and isolating them in a small, standardized
library. It has the disadvantage that it only works with fairly stock
UNIX versions, but a different approach will be used for other
systems.

  This package supplements the existing libraries and header files
of a AT&T-derived Unix system (System V and BSD in particular). It
also provides function prototypes when the compiler supports them,
improving compile-time error checking and improving portability on
machines where sizeof(int) == sizeof(size_t) == sizeof(void*) does not
hold.

  A different approach will be used for the DOS, Atari St, Minix,
and possibly V7: a complete replacement standard C library will be
provided as a separate package. This would not be practical with BSD
or NFS systems because of the conflicts with the host stdio and the
replacement stdio in libc's getpwent().

Contents:
	stdc/*:		The standard C header files and library.
	posix/*:	The POSIX header files and library.
	h/*, h/sys/*:	Links to the header files in stdc/ and posix/.
	libstdc.a:	The standard C library.
	libposix.a:	The POSIX emulation library.

Building PD Ksh
---------------

 First, create the header files and libraries:

	- define _BSD, _SYSV, or _V7 in stdc/Makefile and posix/Makefile
	- rm stdc/stdio.h
	- cd stdc; make link; make
	- cd ../posix; make link; make

 Now, type:

	- cd ../src; make

 The executable will be in src/ksh.

		   Notes on the standard C package

  - The files <locale.h>, <assert.h>, and <math.h> don't exist yet.
  - Many standard C functions are not implemented yet, including
	strtol	strtoul	atexit tempfile		et al.
  - The string routines are by Henry Spencer.

		      Known Portability Problems

  - size_t or ptrdiff_t in <stddef.h> may need to be long.
  - some versions of Unix may scream when make stdc tries to create a
    stdio.h from /usr/include/stdio.h and stdc/stdio.h_std .. if this
    is the case (e.g. on Xenix and some BSD/SysV mixes), you can do it
    by hand by simply doing: 
	cd stdc
	cp stdio.h_std stdio.h
	edit the new stdio.h and insert /usr/include/stdio.h between the lines
		/* system stdio.h goes here ... %%% */
	and
		/* ... end system stdio.h */

  - FILE must be in the host stdio.h for setvbuf() to work; also it
    has to be stock System V or BSD, or it'll fail
  - You can safely "#if 0" out the body of setvbuf for PD ksh, setvbuf
    is used to decrease the size of buffers to speed up forks.
  - If the offsetof macro makes your build fail, define BAD_OFFSET in
    the CFLAGS variable in src/Makefile, as such:
		CFLAGS= blahblahblah -DBAD_OFFSET
  - Also previous versions would crash if you did a Ctrl-D (EOF) on
    the line by itself (at least on Suns); this has been fixed (at
    least on Suns :-)).

		      Notes on the POSIX package

  - Only headers and function required by the PD KornShell are
    implemented. I do not intend to develop this into a full POSIX
    emulation package.
  - You should install Doug Gwyn's <dirent> package if you do not have
    <dirent.h> nor <sys/dir>. If you do have <dirent.h>, unlink
    h/dirent.h (this should be configured automatically by the
    makefile).


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--
     Brendan Kehoe - Widener Sun Network Manager - brendan at cs.widener.edu
  Widener University in Chester, PA                A Bloody Sun-Dec War Zone
-- 
     Brendan Kehoe - Widener Sun Network Manager - brendan at cs.widener.edu
  Widener University in Chester, PA                A Bloody Sun-Dec War Zone