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/*
** PRTSTAT.H - Header file for PRTSTAT.C
*/
#ifndef PRTSTAT_H
#define PRTSTAT_H
struct PrStatus {
unsigned int timeout : 1;
unsigned int unused : 2;
unsigned int IOerror : 1;
unsigned int selected : 1;
unsigned int paperout : 1;
unsigned int ack : 1;
unsigned int notbusy : 1;
};
int prtstat(unsigned int);
#endif
/*** End of PRTSTAT.H *******************************************************/
/*
** PRTSTAT.C - Determine printer status
**
** public domain by Bob Stout
*/
#include <dos.h>
#ifndef PRTSTAT_H
#include "prtstat.h"
#endif
/*
** prtstat() - Call with printer number (0 = LPT1, 1 = LPT2, 2 = LPT3)
**
** Returns status which can be mapped to a PrStatus struct
*/
int prtstat(unsigned int printer_no)
{
union REGS regs;
regs.h.ah = 2;
regs.x.dx = printer_no;
int86(0x17, ®s, ®s);
return regs.h.ah;
}
#ifdef TEST
#include <stdio.h>
#define show(x) printf(#x" is %strue (LPT1)\n", mystat.x ? "" : "not ");
void main(void)
{
struct PrStatus mystat;
*((int *)&mystat) = prtstat(0);
show(notbusy);
show(selected);
show(paperout);
}
#endif
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