README

Hello, AS-Users,

OK, here it is, the C-Version of AS that is theoretically compilable
on any system that has an ANSI-C-compiler!  After a couple of
optimizations, the performance degradations due to the way C handles
strings have been compensated, so the C version should effectively run 
a bit faster than the original Pascal version.

LICENSING

AS is based upon the Gnu General Public License (GPL); read the file
COPYING for its details.  You should have received a copy of this file
together with AS; if not, someone sneaked in!

PLATFORMS

The C version of AS was designed primarily to work with a Unix-like system
with an ANSI-C compilant compiler.  Specifically, I have tested this version
of AS on the following machines:

- Digital Unix 3.2/4.0 with DEC-C
- Digital Ultrix for Mips 4.3/4.5 with gcc 2.7.2
- Digital Ultrix for VAX 4.1/4.5 with gcc 2.7.2
- Linux/Alpha with gcc 2.7.2
- Linux/Intel with gcc 2.7.2
- HP9000/7xx HP-UX 9.0/10.0 with HP-C
- MS-DOS with Borland-C 3.1 resp. 4.5
- OS/2 with emx 0.9
- Munix V.3 with cc
- NetBSD/Sun3 with gcc 2.7.2
- NetBSD/pmax with gcc 2.7.2
- SGI Irix 5.3/6.2 with SGI-C
- SunOS 4.1.3/Sparc with gcc 2.6.3 or cc
- Solaris 2.5/Sparc with Sun-C 3.0.1
- IBM RS/6000 AIX 4.1 with IBM XLC 

DIFFERENCES / THINGS TO DO

The portable C version of AS has the following, known differences to
the original BP version:

- Floating point values are internally only stored as IEEE double 
  precision values, not in the 80-bit format Intel NPUs use. 
  Therefore, floating point ranges and accuracy are not as good as in
  the BP version.  Currently, there seems to be no portable,
  standardized 128-bit-format for FP numbers.  Every vendor (IBM,
  SUN, CRAY, SGI...) uses his own format, so supporting them all
  looks like a lot of work...

+ On most systems, integer arithmetic is done with 64-bit-numbers. 
  This should hurt only programs that explicitly exploit overflow
  and sign effects on 32-bit-versions of AS.

- String variables must not contain NUL characters.  This is due to 
  the fact that C uses the NUL character as an end-of-string marker,
  and is probably the hardest thing to resolve :-(

~ most UNIX systems name their own assembler already 'as', so I had
  to modify the name to 'asl'.  The additional letter is to the honor
  of a person that did quite a lot to spread the UNIX philosophy ;-)
  I also had to rename 'bind' to 'pbind', but I guess that this won't
  matter too much as it is a rarely used tool.

- the C version was designed to have exactly the same command line
  interface as the original BP version; however, UNIX shells
  interprete some special characters like the dollar sign for hex
  values in their own way, so you might have to work with escape (\)
  and quote characters.

+ the USEXMS resp. USEEMS and ASXSWAP environment variables do not
  exist for Unix platforms (thankfully).

- the AS2MSG filter does not exist (wouldn't make sense because there
  is no Borland Pascal for Unix.)

+ This version now contains dynamic switching of program messages, i.e.
  you do not have to compile AS any more for a specific language.  Instead,
  AS will test the LC_MESSAGES, LC_ALL, or LANG environment variables
  on Unix resp. the COUNTRY settings on OS/2 and MSDOS to dynamically
  load the correct set of messages at runtime.


INSTALLATION

See the file 'INSTALL'

FEEDBACK

In case of problems or questions, send them to alfred@ccac.rwth-aachen.de .