From:	SMTP%"tihor@acf3.NYU.EDU" 18-JAN-1991 23:14:23.08
To:	tihor@acf3.NYU.EDU
CC:	
Subj:	Re: Re(2): SET HOST/DER, modem writing

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Date: Fri, 18 Jan 91 23:11:51 -0500
From: tihor@acf3.NYU.EDU (Stephen Tihor)
Message-Id: <9101190411.AA17891@acf3.NYU.EDU>
To: tihor@acf3.NYU.EDU
Subject: Re: Re(2): SET HOST/DER, modem writing
Newsgroups: comp.os.vms
In-Reply-To: article <00942dbd.0616bf40.1374@SOL1.GPS.CALTECH.EDU> of 17 Jan 91 22:50 EST

/* acf3:comp.os.vms / carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick) / 10:50 pm  Jan 17, 1991 */

 > > 	Does anyone know how to use SET/HOST/DTE TXnn: and issue commands from
 > > a batch job? I have some modems connected to the TX ports with callback
 > > security. To change the callback information e.g. telephone numbers), I have to
 > > do this manually as SET/HOST/DTE only works interactively. The modem call back
 > > information is long, complex with heaps of CTRL/characters, and no CR until the
 > > very END!

 > I had a similar problem trying to control a serial line with set host/dte
 > from a .com file.  Couldn't get it to work so I called DEC support.  They told
 > me that it cannot be done except interactively.  It wouldn't be that hard to
 > write a short program to use QIOs to read and write data directly to and from
 > the serial line.

Here's a program I wrote to do about the same thing that SET HOST/DTE does,
with the exceptions that:
	1)  It doesn't disable flow control on the other end, so it's nowhere
	    near as susceptible to data overruns; and
	2)  It doesn't send the initial carriage return to the other end.
It shouldn't be too difficult to modify it to read from a file instead of a
terminal.  Hope this helps.

#include stdio
#include iodef
#include ssdef
#include ttdef
#include tt2def
#include descrip

#define QUEUE(a,b,c,d,e,f) SYS$QIO(a,b,c,d,0,0,e,f,0,0,0,0)
#define ckstat(x) if (((STAT = x) & 7) != 1) SYS$EXIT(STAT)
#define CLEAN(x)  if(((STAT = x) & 7) != 1) \
    {   cleanup(chans,termchar); SYS$EXIT(stat);  }
long STAT;

#define ESCCHR ('\\' & 0x1F)

sethost()
{   struct
    {   unsigned short status, count;
	unsigned char term, dummy, trmlen, linel;
    } iosb[2];
    $DESCRIPTOR(port, "TXA3");
    $DESCRIPTOR(termname, "TT");
    $DESCRIPTOR(mess, "Type control backslash (^\\) to exit");
    static long funcs[3] =
    {   IO$_WRITEVBLK | IO$M_BREAKTHRU,
	IO$_READVBLK | IO$M_TIMED,
	IO$_READVBLK
    };
    long termchar[3], tmpchar[3], efn, efs, stat;
    short chans[2], stm, chan, func, cnt;
    unsigned char buffer[2][255];

    LIB$PUT_OUTPUT(&mess);

/* Assign channel to remote line */
    ckstat(SYS$ASSIGN(&port, &chans[1], 0, 0));
/* And get terminal characteristics */
    ckstat(SYS$QIOW(0,chans[1],IO$_SENSEMODE,&iosb[0],0,0,tmpchar,12,0,0,0,0));
    ckstat(iosb[0].status);
/* Then set modified characteristics */
    tmpchar[1] |= TT$M_NOECHO | TT$M_HOSTSYNC;
    tmpchar[2] |= TT2$M_PASTHRU;
    ckstat(SYS$QIOW(0,chans[1],IO$_SETMODE,&iosb[0],0,0,tmpchar,12,0,0,0,0));
    ckstat(iosb[0].status);
/* Assign channel to local line */
    ckstat(SYS$ASSIGN(&termname, &chans[0], 0, 0));
/* And get terminal characteristics */
    ckstat(SYS$QIOW(0,chans[0],IO$_SENSEMODE,&iosb[1],0,0,termchar,12,0,0,0,0));
/* Then set modified characteristics */
    tmpchar[0] = termchar[0];
    tmpchar[1] = termchar[1] | TT$M_NOECHO;
    tmpchar[2] = termchar[2] | TT2$M_PASTHRU;
    ckstat(SYS$QIOW(0,chans[0],IO$_SETMODE,&iosb[1],0,0,tmpchar,12,0,0,0,0));
    ckstat(iosb[1].status);
/* Set up MODEM for appropriate operation */
    CLEAN(QUEUE(3,chans[1],funcs[2],&iosb[0],buffer[0],1));
    CLEAN(QUEUE(7,chans[0],funcs[2],&iosb[1],buffer[1],1));
    while (SYS$WFLOR(1,204) == 1)
    {   for(efn = 2; efn < 8; ++efn)
	{   if(((efn & 2) == 2) && SYS$READEF(efn, tmpchar) == SS$_WASSET)
	    {   SYS$CLREF(efn);
		stm = efn/4;
		func = efn & 1;
		chan = func ^ stm;
		cnt = iosb[stm].count + iosb[stm].trmlen;
		stat = iosb[stm].status;
		if (stat == SS$_NORMAL || ((stat == SS$_TIMEOUT) && cnt > 0))
		{   if(func == 1)
		    {	if(stm == 1 && find(ESCCHR, buffer[stm], cnt))
			{   cleanup(chans,termchar);
			    SYS$EXIT(1);
			}
		    }
		    efn ^= 1;
		    func ^= 1;
		    chan ^= 1;
		    if (func == 1)
			cnt = 255;
		    CLEAN(QUEUE(efn,chans[chan],funcs[func],&iosb[stm],
			buffer[stm],cnt));
		}
		else if(stat == SS$_TIMEOUT && cnt == 0 && func == 1)
		{   func = 2;
		    CLEAN(QUEUE(efn,chans[chan],funcs[func],&iosb[stm],
			buffer[stm],1));
		}
		else
		{   cleanup(chans,termchar);
		    SYS$EXIT(stat);
		}
	    }
	}
    }
}

find(c,s,n)
char c, *s;
int n;
{	for(--n; n >= 0 && *s != c; ++s, --n);
	return(n >= 0);
}

cleanup(chans, termchar)
short chans[2];
long termchar[3];
{	SYS$CANCEL(chans[0]);
	SYS$CANCEL(chans[1]);
	SYS$QIOW(0,chans[0],IO$_SETMODE,0,0,0,termchar,12,0,0,0,0);
}
/* ---------- */