/*
 *	@(#)unpit.c	1.2	(CWI)	87/11/05
 */

/*

		unpit - Macintosh PackIt file unpacker

		Version 2, for PackIt II

This program will unpack a Macintosh PackIt file into separate files.  The
data fork of a PackIt file contains both the data and resource forks of the
packed files.  The program will unpack each Mac file into separate .data,
.rsrc., and .info files that can be downloaded to a Mac using macput.

The program syntax is much like macput/macget:

	unpit [-rdu] packit-file.data

The  -r and -d flags will cause only the resource and data forks to be
written.  The -u flag will cause only the data fork to be written and
to have carriage return characters changed to Unix newline characters.

Some of the program is borrowed from the macput.c/macget.c programs.

	Author: Allan G. Weber, (Weber%Brand@USC-ECL)		
	Date:   September 30, 1985
	Revised: January 24, 1986 - added CRC checking
		 March 25, 1986 - support compressed mode of PackIt II,
				  check for illegal Unix file names

*/

/* There is some confusion as to what to do with the "inited" flag in the
   finder info bytes that are in the header of each file in the packit file.
   If this flag bit is copied to the .info file, it seems to confuse
   MacTerminal into placing the file icons in the upper left corner of the
   window on top of each other.  Setting this bit to zero in the .info file
   seems to fix that problem but may cause others.  I haven't been able to
   find any .info files that have this flag set so making it zero may be OK.
   Anyway, MacTerminal seems to set the flag when it create the file on the
   Mac.  The "#define INITED_BUG" can be used to try both settings.  */

/*
Format of a Packit file:

Repeat the following sequence for each file in the Packit file:

	4 byte identifier ("PMag" = not compressed, "Pma4" = compressed)
	variable length compression data (if compressed file)
	92 byte header (see struct pit_header below) *
	2 bytes CRC number *
	data fork (length from header) *
	resource fork (length from header) *
	2 bytes CRC number *

Last file is followed by the 4 byte Ascii string, "Pend", and then the EOF.

* these are in compressed form if compression is on for the file

*/