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#include <u.h>
#include <libc.h>
#include "/386/include/ureg.h"
static uchar buf[0xFF01];
void
main(int argc, char *argv[])
{
struct Ureg u;
int fd, rreg, rmem, len;
ARGBEGIN {
} ARGEND;
if(argc == 0){
fprint(2, "usage:\t%s file.com\n", argv0);
exits("usage");
}
if((fd = open(*argv, OREAD)) < 0)
sysfatal("open: %r");
if((rreg = open("/dev/realmode", OWRITE)) < 0)
sysfatal("open realmode: %r");
if((rmem = open("/dev/realmodemem", OWRITE)) < 0)
sysfatal("open realmodemem: %r");
if((len = readn(fd, buf, sizeof buf)) < 2)
sysfatal("file too small");
memset(&u, 0, sizeof u);
u.cs = u.ds = u.es = u.fs = u.gs = 0x1000;
u.ss = 0x0000;
u.sp = 0xfffe;
u.pc = 0x0100;
seek(rmem, (u.cs<<4) + u.pc, 0);
if(write(rmem, buf, len) != len)
sysfatal("write mem: %r");
if(write(rreg, &u, sizeof u) != sizeof u)
sysfatal("write reg: %r");
}
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