🚀 go-pugleaf

dahls@fhydra.dnet.unit.no (Joern Yngve Dahl-Stamnes) writes:

>Hello.

>I'm doing a fprintf (stdprn,...) in program. The only problem is that if the
>printer isn't on-line, I get this annoying message on the screen. The message
>is annoying because my program is a screen oriented program.

>Is there any way to trap this fault so that my program can display the message
>(or my own message) on the screen when this happen? I've been looking in the
>FAQ, but could not find it.

You might like to try using the Int17h functions to get the printer status
and write to the printer...

#include <stdio.h>
#include <dos.h>

#define OUT_OF_PAPER    0x20
#define IO_ERROR        0x08

void print(char *str)
{
    union REGS regs;

    regs.x.dx = 0;
    while (*str) {
        regs.h.ah = 0x00;
        regs.h.al = *str;
        int86(0x17, &regs, &regs);
        ++str;
    }
}

int prn_ok(void)
{
    union REGS regs;

    regs.h.ah = 2;
    regs.x.dx = 0;
    int86(0x17, &regs, &regs);
    if (regs.h.ah & OUT_OF_PAPER) {
        puts("Printer is out of paper");
        return 0;
    }
    if (regs.h.ah & IO_ERROR) {
        puts("Printer IO error");
        return 0;
    }
    return 1;
}

void main(void)
{
    if (prn_ok()) {
        print("Printer is on-line and okay!");
    }
}

Lee Hollingworth
s1110238@giaeb.cc.monash.edu.au