intro.txt

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The UCR Standard Library for Assembly Language Programmers,
Written By Randall Hyde and others, is

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We do not want any registration fees for this software.

Now for the catch...  It is more blessed to give than to receive.  
If this software saves you time and effort and you enjoy using it, 
our lives will be enriched knowing that others have appreciated our work.  
We would like to share this wonderful feeling with you.  If you like this 
software and use it, we would like you to contribute at least one routine to 
the library.  Perhaps you think this library has some neat-o routines in it.  
Imagine how nice it would become if everyone used their imagination to 
contribute something useful to it.

We hereby release this software to the public domain.  You can use it in any
way you see fit.  However, we would appreciate it if you share this software 
with others as much as it has been shared it with you.  That is not to suggest
that you give away software you have written with this package (We're not 
quite as crazy as Richard Stallman, bless his heart), but if someone else would 
like a copy of this library, please help them out.  Naturally, we would be 
tickeled pink to receive credit in software that uses these routines (which is 
the honorable thing to do) but we understand the way many corporations operate 
and won't be terribly put off if you use it without giving due credit.  

Enjoy!

If you have comments, bug reports, new code to contribute, etc., you can 
reach us through (address and email are circa 1993, if you read this in
1999, don't count on it!):

		[e-mail]		(On Internet).

or

		Randall Hyde
		Dept of Computer Science
		100 University Office Bldg
		University of California
		Riverside, Ca. 92521


COMMENTS ABOUT THE CODE:
************************

Please don't expect super optimal code here.  Most of it is fairly mediocre
(from a size/speed point of view).  Hopefully, you'll agree, it's the idea
that counts.  If you do not like something I have done, you have got the
sources -- have at it.  (Of course, it would be appreciated if you would
send any modifications to one of the E-MAIL addresses above.)


****************+******************** NOTE ************************************

Please understand the purpose of this code!  This library is here to make
assembly language programming easy.  The nature of this library encourages
people to write code in a fashion similar to that employed when they write
programs in a high level language like C.  While this familiar style of
programming does make the task easier, it is not the most appropriate
approach to use when flat-out performance is what you're seeking.  "C code
written with MOV instructions" is never as fast as pure assembly language
code employing the proper programming paradigm.  Why mention this?  Well,
some readers may have heard about assembly language's legendary performance
and they're expecting to achieve that using this library.  While programs
written with this library may very well run faster than a comparable program
written in a HLL, you will not get fantastic performance improvement until
you stop thinking in HLLs and starting "thinking" in assembly.  The purpose
of this library is to help you *avoid* thinking in assembly language.  There-
fore, this code will not help you achieve those fantastic performance levels
you've been hearing about; indeed, this library may stand in the way of that
goal.  It's not that these routines are terribly slow, mind you.  They just
encourage an inappropriate programming style if speed is what you're after.

On the other hand, since only 10-20% of the code of any given program
represents the time critical stuff (an argument long employed by HLL
supporters), there is nothing wrong with judicious use of this code within
a program that has to be fast.  As usual, if performance is your primary
goal, you must study the problem and the program you generate very carefully
to isolate the time critical portions.  If you are interested in high-
performance programming at the "micro-algorithm" level, you should take a look
at Michael Abrash's text "Zen of Assembly."  This excellent book will explain
many ways to improve the performance of your code at the sub-algorithm level
(where assembly language really shines).



COMMENTS ABOUT THIS DOCUMENTATION:
**********************************

You will have to forgive us for the inconsistent style appearing throughout
this document.  Keep in mind that this document has been prepared by many
different people.  Keeping the styles consistent is a time consuming and
difficult task.

Whenever a routine's description claims that the flags are not affected,
you should not interpret this to mean that the routine preserves the flags.
Most routines do *not* preserve any of the flags.  Such a statement simply
means that the routine does not *explicitly* return a value in one (or more)
of the flag bits.

Note that proper credit has been given to the author of each of the various
routines appearing in this library *except* for many written by Randall
Hyde.  All routines without an author by-line were probably written by
Randall Hyde (unless we screwed up somewhere and forgot to put a name
in the documentation).  Most of these routines were tested and documented
by various students in Randy Hyde's CS 13 (assembly language) and CS 191X /
CS 185 courses (Commercial Software Development).  There are too many names
to mention here, but these students definitely deserve the credit for locating
numerous bugs in the code, providing many suggestions, and doing other work.

Of course, there have been numerous suggestions and bug notices from helpful
souls on BIX and the Internet, as well.  Thank you all.

*NOTICE* We have noticed, from time to time, that there are routines in the
library which have not been documented.  Perusing the source listings will
help you locate some library routines which have slipped through the cracks.
Also keep in mind that there isn't a one to one correspondence between
source files and library routines.  Many of the source files contain
two or more library routines.  Someday we will attempt to document which
files contain which routines, but that's in the future for now.

=============================================================================

Version History:

Version 00- 	Initial release as "Randy Hyde's Standard Library for 80x86
		Assembly Language programmers"

Version 10-	Initial release as "UCR Standard Library..."  CS 191X
		students did some testing and documentation in this release.

Version 20-	More testing on several routines.  Added floating point
		library and several other routines.

Version 21-	Fixed *MAJOR* bugs in floating point package.  Added
11-1-91		several new routines.  Included new "TEST" files with
		the library.  Also included SHELL.ASM file inadvertently
		left out of Version 2.0.

Version 22-	Made some minor modifications to puth, putl, ltoa, and htoa
11-14-91	as per suggestions made by David Holm and Terje Maithesen

Version 23-	Made a small but *major* modification to the stdlib.a and
11-22-91	stdlib.a6 files to force library calls into the STDGRP group.
		Otherwise the linker substitued bad segment addresses for
		the far calls to the library routines.  A real problem when
		accessing variables in StdData.

Version 24-	Yet more changes to fix the stupid MASM group/segment:offset
12-7-91		bug.  Made various changes to the STDLIB.A file.  Also fixed
		a problem in the FP routines- forgot to declare sl_sefpa
		public.  Finally, created batch file to automatically unpack
		everything from DOS (assuming presence of PKUNZIP somewhere
		in the current path).

Version 25-	Some new macros (DOS, ExitPgm), fixed a problem with the
12-25-91	PUTI routine, added some SmartArray items.  Also added the
		GetEnv routine.

Version 26-	Maintenance release coinciding with the Dr. Dobb's article
2/20/92		in the March 1992 issue.

Version 27-	SmartLists and interrupt driven serial routines added to
6/19/92		the libraries.  Also created smaller include files for
		each of the standard library categories. (note: the serial
		routines actually existed prior to this release, they were
		cleaned up and documented for this release).  Fixed a couple
		of truly disgusting bugs in the floating point package
		(wouldn't properly print values like 8100 and hung whenever
		encountering a zero value in FADD/FSUB).

Version 28-	Modified MemInit to allow the programmer to specify how many
8/20/92		pages to reserve for the heap and the location of the heap.

Version 29-	Added HeapStart routine to the memory management code so an
10/5/92		application could get the segment address of the start of
		the heap.  This is useful when you want to deallocate the
		heap (by calling DOS' deallocate routine), for example, to
		free up the heap memory so you can run another application.
		What really needs to be done here is to write a dealloc
		routine, but HeapStart offered some flexibility.

Version 30-	Fixed bug in ATOH2 routine (it incremented DI once too far).
10/11/92-	Also fixed the same bug in ATOI2, ATOU2, ATOL2, ATOUL2, etc.
3/16/93		Added StrTrim (m) and StrBlkDel (m) to the library.  Added
		the pattern matching package to the library. Added the date
		and time routines (ATOD, DTOA, DTOA2, DTOAm xDTOA, xDTOAm,
		xDTOA2, ATOT, TTOA, TTOA2, TTOAm xTTOA, xTTOAm xTTOA2) to
		the library.  Fixed a bug in ATOI and ATOL which passed off
		the ":" character as a numeric digit.  Broke the MemInit
		routine into two separate routines: MemInit & MemInit2 which
		let the user specify the location of the heap or use all the
		available memory.  Also, no longer require that PSP be a
		global variable (However, the library does require DOS 3.3
		or later).  Fixed a bug in PRINTF/PRINTFF (it did not
		properly restore the flags and BP). Fixed a bug in the
		LSFPO routine (thanks to Tim Farley for pointing this out).
		Added the process manager package to the library.

Version 31-	Fixed a bug in strstr which prevented it from matching a
6/10/93		substring at the beginning of a string.  Added file
7/24/93		routines to the library.  Added macros for strbdel and
8/1/93		strtrim to string.a.  Fixed a bug in stricmpl, forgot to
		copy a pointer into SI within the routine.  Fixed a bug in
		CPUID which crashed the machine if a 486.

Version 32-	Fixed several bugs in the list routines.  Added some actual
3/24/94		file routines to the library.  Updated the documentation.

Version 33-	Fixed some bugs in the floating point code.  Fixed a bug
7/15/94		a bug in the pattern matching code.  Added new pattern
		match routines.  Changed the name of CPUID because it
		conflicts with the Pentium instrucion of the same name.
		Fixed several bugs in the processes package.  Fixed some
		problems in the documentation (certain routines were listed