MS-DOS SHELL

MS-DOS Shell Version 2.3 README September 1994 MS-DOS SHELL - Copyright (c) 1990,4 Data Logic Limited and Charles Forsyth This code is based on (in part) the shell program written by Charles Forsyth and is subject to the following copyright restrictions: 1. Redistribution and use in source and binary forms are permitted provided that the above copyright notice is duplicated in the source form and the copyright notice in file sh6.c is displayed on entry to the program. 2. The sources (or parts thereof) or objects generated from the sources (or parts of sources) cannot be sold under any circumstances. $Header: /usr/users/istewart/shell/sh2.3/Release/RCS/ReadMe,v 2.3 1994/08/25 20:58:47 istewart Exp $ $Log: ReadMe,v $ Revision 2.3 1994/08/25 20:58:47 istewart MS Shell 2.3 Release Revision 2.2 1993/12/03 13:32:52 istewart Release 2.2 Revision 2.1 1992/12/14 11:14:32 istewart BETA 215 Fixes and 2.1 Release Revision 2.0 1992/04/13 17:40:33 Ian_Stewartson MS-Shell 2.0 Baseline release ________________________________________________________________________________ This is an implementation of the Unix Shell for MSDOS. As far as possible it is compatible with the System V.4 program sh(1) with ksh(1) extension. The following differences are noted: 1) Background or asynchronous commands are not supported under MSDOS. Some support is provided under OS/2, but it is not as full as UNIX. You can only run one command and not a pipeline in background. 2) Certain internal commands which have no equivalent MSDOS or OS/2 supported functionality support (ulimit, time etc) are not provided. 3) Command hashing and accounting are not supported. 4) Some of the ksh functionality has not yet been implemented or made ksh compatible (see Notes file). 5) The Shell uses all variables starting with a ~ (tilde) internally and will not allow you to display them. I don't think this is a difference from the user's view, just internally. The Shell has been tested mainly under MSDOS 3.3, 4.01, 5.2, 6.0 and 6.2, OS/2 1.3, 2.0 and 2.1, and a prelimiary version can be built for Windows NT 3.1 (see notes files on this). It has exposed some shortcomings in the C6.0 compiler and MSDOS library. As such, using C5.1 and its library are prefered when re-building the shell for MSDOS. The following enhancements have been made for the MSDOS environment. These enhancements are described in the appropriate section of the manual pages. 1) Under MSDOS (16-bit version), the Shell will swap itself out to one of the following: - Expanded memory - Extended memory - Disk (this is the slowest) The swapping is controlled by the shell internal command swap. If swapping is enabled, the shell only uses 3K of memory whilst a child process is executing. Note: Swapping to Extended memory is probably the most dangerous unless you have an XMS memory manager available. The shell requires the XMS manager to support the version 2 XMS specification. 2) Command line editing has been added for non VI or EMACS mode. A configuration file (sh.ini) allows the Command Line editing keys to be tailored to the users requirements. 3) The command line prompt can be programmed to display 'useful' information. 4) The shell uses Unix format file names (ie slashes and not backslashes) to delimit directories. Some programs require certain environment variables to be in MS-DOS format (using backslashes). The msdos or typeset -H commands allows these variables to be marked so that they are set correctly when the environment for a program is set up. 5) The format of the command line which the shell passes to a program is configurable between normal, indirect files and environment variables (see SH.1). A version of stdargv.c which supports the indirect file format (and wildcards from a normal command line) is included. 6) Wild cards on drives (ie echo *:*.c will echo all the C files in the current directories of each drive) are supported. 7) Full Interrupt 24 processing has been added. 8) Alternate command interpreters are supported in shell scripts a la Unix V.4. 9) A number of OS/2 internal commands (start, detach) have been addded. 10) The Notes file describes the fixes and changes between Release 2.2 and 2.3 11) Significant parts of the shell have been re-written this release 2.1. The following Bugs are known to exist in the Shell. 1) See Notes file. 2) I may have mis-interpreted the functionality of either the UNIX version of sh or ksh (tell me about it). The shell was built using Microsoft C 5.1 and MASM v5.1 in large model mode for MSDOS and Microsoft C6.0 for OS/2 (16 bit) and WATCOM 9 for both 32-bit versions (although EMX GCC 2.5 is supported for the 32 Bit version under OS/2). In addition, the version of open in your library must pass the O_NOINHERIT bit on the MSDOS kernel. The Microsoft C v5.1 library (and possibly the v6.0) does not pass this bit on to the MSDOS open System call. I fixed this using CodeView to find where the library function masks off the bottom 2 bits. Extracted the object from the library and patched mask from 0x03 to 0x83 in the object and reload into the library. No Problem. The Patch.Lib document describes the process in more detail. You can do want you like with this software as long as you don't sell it or remove the Copyright notices in the sources or object. If you have any problems or want to let me know about any enhancements, I'd love to hear about them. However, following this release, I will be leaving Data Logic in the middle of September 94. I will not have an E-Mail address at my new company, until I arrange a personal account in the New Year. I expect to be in Europe for three months and will not arrange the personal account until I return. You should be able to contact me by surface mail at the address below, but don't expect a rapid response. Ian Stewartson OSI Group Metropolis House 22 Percy Street London W1P 9FF United Kingdon. Please don't contact Data Logic as it is unlikely have anyone there will know anything about the shell. Note: Unix is a registered trademark of AT&T Bell Laboratories Microsoft, MSDOS, MASM, MS Windows, Windows NT and CodeView are registered trademarks of Microsoft Corporation OS/2 is a registered trademark of Internation Business Machines Corporation Acknowledgements: This program is based on ideas, code or parts of code developed by: David Korn and Steve Bourne (the original ideas) Charles Forsyth (original source for the MINIX Shell program) Erik Baalbergen (original source for the MINIX test program) Paul Falstad (original source for the maths functions from GNU zsh program) Simon J. Gerraty (the code for the new lexical analyser and the VI/EMACS edit functions). Ideas and fixes from lots of others.