Baslinux mailing list

[sindi keesan <keesan AT sdf.lonestar.org>]

On Mon, 25 Apr 2005, David Moberg wrote:

> ----- Original Message -----
> From: "sindi keesan" <keesan AT sdf.lonestar.org>
>
> > > > The doc file has a lot of <FF) and @^ and then <89>PNG.  At the end
> > > > it has more <FF> and @^ and then something about WORD.
> > > >
> > > > I could probably just use a text editor to manually chop off the
> > > > beginning and end of this sort of doc file instead of wvware, but
> > > > can someone suggest a script which would delete all characters
> > > > before <89>PNG
> > >
> > > #!/bin/sh
> > > export POSIXLY_CORRECT=""
> > > expr index "`cat $1`" "`echo 3PNG | tr 3 '\211'`" >/tmp/1
> > > expr `cat /tmp/1` - 1 >/tmp/1
> > > expr `cat $1 | wc -c` - `cat /tmp/1` >/tmp/1
> > > tail -c `cat /tmp/1` $1
> > > rm -f /tmp/1
> >
> > I have non-busybox tail and busybox tr, wc, cat, and expr.
>
> wc and expr are probably fouling things up. Please try the full
> versions.

/a15/txtutils.tgz has tr, wc, cat, tail
/a11/sh_utils.tgz has expr
/n6/wget.tgz

Anything else I should install to replace busybox?

I again ran this script calling it doctopng (I created it by downloading 
your email and trimming off top and bottom).  doctopng doc1.doc > doc1.png

expr:  syntax error
tail:  doc1.doc invalid number of bytes

I have now /usr/bin/expr not busybox.

No /tmp/1 file was created.  I am running this as root in /tmp (the script 
and the starting .doc file are in /tmp).

> > How did <80>PNG become 3PNG?
>
> It didn't.
>
> echo 3PNG | tr 3 '\211'
>
> tr changes 3 to '\211' which equals <89>

If <89> is hexadecimal is that 8x16+1 (129)?
If so, what system is 3 and \211?


> > I downloaded this email and copied the above to a program doctopng,
> > chmod +x'ed it, and then typed doctopng doc1.doc > doctopng.png
> >
> > I get the error message:
> > tail: doc1.doc:  invalid number of bytes
>
> wc is probably not giving correct output. With the POSIXLY_CORRECT
> environment variable set to "", my wc gives the following output:
>
> $ wc -c file
> 345
>
> The number given should equal the filesize in bytes. There should
> only be one number. Also, there should be no indentation.
>
> > Are you using wc to count the number of bytes before PNG and then
> > trying to remove that number of bytes from the start of the file
> > with tail?
>
> Yes.

> > > > The png file ends with IEND<AE>B`<82>.  The WORD file continues
> > > > with many pages of @^ (to encourage you to get a larger hard
> > > > drive?) and <FF> and then the names of the two people working at
> > > > that office repeatedly, some comments on what is in the document
> > > > that they probably added, and various mentions of Microsoft Word
> > > > 9.0.  So I could also just chop that off.
> > >
> > > Do you want a script that does that, too?
> >
> > One that does both would be ideal so that I will have just the PNG part.
> > I had no idea it would be that complicated.  With pico I just
> > search on PNG and END and delete by blocking and Ctrl-K.
>
> Get this one working first. Another one to trim the end off will be much
> easier.
>
> > > > <82> is presumably a hex character and perhaps a shell script would
> > > > need to refer to it differently.
> > >
> > > Very differently for <89>. The method I used above is very ugly.
> >
> > Maybe there is a simpler way?
>
> Not likely. A C program would be simpler for me.
>
> > Yes, this file starts and ends exactly the same way as the one in the doc.
> > <89>PNG and IEND....<82>
>
> OK. I will work on a variant to trim the end off.



> David
> --

Sindi