MCOMM ASYNC LIBRARY NOTES

            This file contains information on configuring the libraries
         for use with your compiler and some Zortech C compiler specific
         notes.  If your application may be ran on a system that uses a
         Western Digital 16550, be sure and read the notes on this chip
         in ASYNC.DOC.  The file, UPDATE.DOC, contains important
         information regarding changes or additions to the library and
         header files.  Be sure and read this file also.  The area code
         for east Texas has been changed from 214 to 903 effective
         November 1, 1990.  After May 1, 1991, the old area code will no
         longer work.  The new numbers are:

            North East Texas Data Link    (903) 838-6713
            Mike Dumdei (voice)           (903) 838-8307


                       LIBRARY AND HEADER FILE INFORMATION

         WHEN UPDATING, ALWAYS UPDATE THE HEADER FILES ALSO !!!

         The composite LIBs listed below contain all the functions des-
         cribed in ASYNC.DOC and SUPLMNT.DOC.  As supplied on the disk
         the LIBs are setup for linking using Microsoft C or Quick C.
         If you use Turbo C you need to run the batch file, TCLIBS.BAT,
         to convert the LIBs to Turbo C format.  If you use Zortech C,
         you will need to run ZTCLIBS.BAT.

         The conversion is necessary because a few of the non-async
         functions are written in C and call library functions that have
         different names in Microsoft C, Turbo C, and Zortech C.  All
         the C code used is included in the shareware version so that if
         you are using a compiler, other than one of the above, that
         does use Microsoft calling sequences, you can recompile the
         code, update the composite LIBs, and still use the library.

         In addition, the following statements are contained in COMM.H,
         ANSIDRV.H, and EXTRA.H:

                         #if !defined(MCOMM)
                           #define _C_ cdecl
                           #define _N_ near
                           #define _F_ far
                           #define MCOMM
                         #endif

         These definitions are not totally up to date with MSC 6.0 and
         QC 2.5 (they have added a leading underscore for ANSI compat-
         ibility), however, they do still work with these compilers and
         they also work with Turbo C 2.0, Zortech C, and previous
         versions of Microsoft's compilers. If you are using a different
         compiler, you may need to change the 'cdecl', 'near', and 'far'
         keywords to the equivalent names used by your compiler.




         Only the small model version of the LIBs is included in the
         shareware version.

         COMPOSITE LIBS:
            COMM_S.LIB     ;small model LIB of all routines
            COMM_C.LIB     ;compact model LIB of all routines
            COMM_M.LIB     ;medium model LIB of all routines
            COMM_L.LIB     ;large model LIB of all routines
            COMM_H.LIB     ;created by TCLIBS.BAT (only used by TC)

         CONVERSION LIBS: (used by TCLIBS.BAT, MSCLIBS.BAT, ZTCLIBS.BAT)
            TC_XS.LIB      ;used to convert COMM_S to TC
            TC_XC.LIB      ;used to convert COMM_C to TC
            TC_XM.LIB      ;used to convert COMM_M to TC
            TC_XL.LIB      ;used to convert COMM_L to TC
            TC_XH.LIB      ;used to convert COMM_L to TC COMM_H
            MSC_XS.LIB     ;used to convert COMM_S to MSC
            MSC_XC.LIB     ;used to convert COMM_C to MSC
            MSC_XM.LIB     ;used to convert COMM_M to MSC
            MSC_XL.LIB     ;used to convert COMM_L to MSC
            ZTC_XS.LIB     ;used to convert COMM_S to ZTC
            ZTC_XC.LIB     ;used to convert COMM_C to ZTC
            ZTC_XM.LIB     ;used to convert COMM_M to ZTC
            ZTC_XL.LIB     ;used to convert COMM_L to ZTC


         Zortech C Specific Information:

            The Zortech C IO.H file and MCOMM COMM.H file have a name
            clash with the defined variable 'R_OK'.  Zortech has it
            defined as 4 and MCOMM defines it as 0.  The MCOMM
            documentation makes references to a return value of R_OK so
            rather than define it out in COMM.H, I left it in.  I
            thought it was better for you to get a compiler error that
            you could find than defining out R_OK if __ZTC__ was defined
            and you not knowing what was wrong when a function that was
            supposed to return R_OK didn't (since R_OK was 4 instead of
            0).  The solution is to define it out of COMM.H if __ZTC__
            is defined and then everywhere an MCOMM function is supposed
            to return R_OK, look for a return value of 0.

            Control-break locks up the SMALTERM demo programs.  I think
            the problem is:  Zortech C control-break causes you to exit
            to DOS where MSC and TC do not as long as only the BIOS key
            functions are used.  When SMALTERM exits to DOS with the
            interrupts still hooked, the demo crashes. This only applies
            to Zortech C/C++.  I tried using the signal functions to fix
            it but didn't get it.  If you are an experienced Zortech
            user and want to tell me how to make Zortech C run the exit
            term function when control-break is pressed before it exits
            to DOS, I will correct it for the next version.