Re: [Expectperl-discuss] SUCCESS! parsing non-ascii char's

[John M. <ex...@h0...>]

On Tue, Apr 08, 2003 at 03:10:44PM -0500, BLACKSTONE, J. DAVID wrote:
> 
> > -----Original Message-----
> > From: Christian Goetze [mailto:cg...@hq...] 
> > Sent: Tuesday, April 08, 2003 2:22 PM
> > To: exp...@li...
> > Subject: Re: [Expectperl-discuss] parsing non-ascii char's
> > 
> > 
> > > Thx for your suggestion and I can see some merit here.
> > > I am, however, starting to think I am off topic for this list.
> > >
> > > My real problem is that I do not have multiple lines of
> > > data to parse. It's all one long line with lots of
> > > control chars.
> > >
> > > When I print the data to a file
> > >   cat <filename>
> > > shows output that looks just like my telnet session.
> > >   cat -v <filename>
> > > shows all the ugly special chars
> > >   wc -l <filename>
> > > shows I have one line of data and
> > >   cat <filename> | wc -l
> > > still tells me I have one line of data.
> > 
> > What you need here is a terminal emulator. If you're really 
> > unlucky, the other side will optimize redraws and you will 
> > not easily get the correct picture. As a first step, you 
> > could simply try ignoring the special chars, but you may end 
> > up having to emulate the screen and do "screen scraping".
> 
>   I have had to do some of that and it was not fun.  Two things that might
> help you:
> 
>   If you capture your session to a file, write a program to "play it back"
> as a "movie" by clearing the screen and sending each character to the screen
> in sequence with a small delay in between (like 0.1 seconds).
> 
>   The terminal garbage may likely include codes that position the cursor.  I
> think in my case those codes were something like escape, control-[ , row,
> semicolon, height, control-G.  Or something awful like that; I can't
> remember what.  But I could parse out the row and column and use it.  I
> wrote a program to take a cut and paste terminal screen capture and print it
> out with - and | characters, with row and column numbers at the top and
> bottom.  I made printouts of these to see where my data displayed, and
> checked the session capture log to make sure the row and column appeared
> exactly in the control garbage.  Watching the movie also became important
> because sometimes things did not print out on the screen in the order you
> would expect.
> 
>   It would theoretically be possible to write a program that maintained an
> 80x24 "screen" array of characters, read the control codes, and updated the
> appropriate places in the array.  If you do, put it on CPAN!!!  But I didn't
> find it necessary.
> 
> jdb

Thanks to everyone for your help.

The biggest things to help me were:
    use \c for reg exp's involving control chars;

    learning that someone else had faced text that
    included strings similar to "escape, control-[ , row,
    semicolon, height, control-G" etc (yuk!);

    reading my text with /usr/local/bin/less which is
    kind enough to display chars like "ESC[12;31HPort:";

Presently, I am successfully parsing this string with:
    #start by stripping the CTRL-[ chars
    $line =~ s/\c[//g;

    #strip the stupid NULL MAC
    $line =~ s/00-00-00-00-00-00//;

    #find the 1st MAC
    if ( $line =~ /(..\-..\-..\-..\-..\-..)/ ) {
        $first_mac = $1;
    }

    #throw away everything before the 1st MAC
    $line =~ s/^.*$first_mac/$first_mac/;

    #replace weird chars before each MAC
    $line =~ s/\[\d+\;1H/\n/g;

    #replace weird chars before each Port
    $line =~ s/\[\d+\;\d+H/\t/g;

    #find the last line and split it off
    if ( $line =~ m#\s+\[\d+K(Press\s.*)# ) {
        $last_line = $1; #(I need this $last_line data too)
        $line =~ s/\s+\[\d+KPress\s.*//;
    }

    @array = split ( /\n/, $line );
    push ( @all_arrays, @array );

Seems like a lot a work to get what I want, but it works
and I can get on with solving a problem.

Thx again for all the help.
--
John Mahoney
ex...@h0...