🚀 go-pugleaf

Dear colleagues:
 
I am trying to write a simple terminal emulation program in C using
Microsoft C 5.1 for MSDOS, tried to use _bios_serialcom() but have
problems with the interpretation of the status returned.
 
At the end of this message is some C code I wrote (it doesn't work).
 
Any help with this will be much appreciated. Please reply by e-mail.
Thanks...
 
             Lucio Menzel -- lumenzel@eastern.uucp
 
-----------------------8<----------------cut----here----------
#include <stdio.h>
#include <conio.h>
 
#define ESC (char)27
 
char bCommGetChar(char cPort, char *pc)
{
// check port to see if there is a byte to read,
// if so read it, asign to *pc and return 1.
// If there's no byte to read return 0
 
        unsigned uStatus;
        uStatus = _bios_serialcom(_COM_STATUS, cPort - 1, 0);
        if (uStatus & ...)
        {
                uStatus = _bios_serialcom(_COM_RECEIVE, cPort - 1, 0);
                if (uStatus & ...)
                {
                        *pc = (char)(uStatus & 0x00ff);
                        return (char)1;
                }
        }
 
        return 0;
}
 
char bCommPutChar(char cPort, char c)
{
// wait until the port is ready and then send the byte
 
        unsigned uStatus;
 
        while (1)
        {
                uStatus = _bios_serialcom(_COM_STATUS, cPort - 1, 0);
                if (uStatus & ...)
                        break;
        }
        uStatus = _bios_serialcom(_COM_SEND, cPort - 1, c);
        return uStatus & ...;
}
                
int main(void)
{
        char c, cPort = (char)1;        // COM1
        unsigned uStatus = 
                _bios_serialcom(
                        _COM_INIT, 
                        cPort - 1, 
                        _COM_EVENPARITY|_COM_CHR7|_COM_STOP1|_COM_1200
                        );
 
        if (uStatus & ...)
        {
                fprintf(stderr, "\7Cant set serial port\n");
                return 1;
        }
 
        puts("ESC to end");
        while (1)
        {
                if (bCommGetChar(cPort, &c))
                        putchar(c);
                if (kbhit())
                {
                        c = (char)getchar();
                        if (c == ESC)
                                break;
                        if (!bCommPutChar(cPort, c))
                                printf("error sending %c\n", c);
                }
        }
 
        return 0;
}
 
/*EOF*/