Re: how to modify string in binary files ?

[Ron Johnson <ron.l.johnson@cox.net>]

On 2009-09-01 01:03, Jerome BENOIT wrote:
> Hello Chris !
>
> Chris Jones wrote:
> > On Mon, Aug 31, 2009 at 08:08:50PM EDT, Jerome BENOIT wrote:
> > > Hello List,
> > >
> > > I would like to change the string of a file name in a (propriety) 
> > > binary:
> > > if applicable, how can we do that ?
> >
> > Use vim's binary mode.
> > $ vim -b binary-file
> >
> > And before you start editing:
> >
> > :h edit-binary
>
> I have just tried.
>
> It is claimed that
>
>  When editing executable files the number of characters must not change.
>  Use only the "R" or "r" command to change text.  Do not delete characters
>  with "x" or by backspacing.
>
> So a string cannot be made longer.
> Can we make a string shorter ?

The program is going to expect certain "stuff" to be at certain 
places within the file.  Adding or removing bytes is *definitely* A 
VERY BAD THING.

> The first idea that comes is to put a '\n' at the desired end of the string
> and then fill the extra with '\0': is it safe.

IFF the app was written in a language that uses \0 as the string 
terminator...

> Otherwise, as no HEX code appears, is `bvi' a good alternative ?

It's what I'd use...

--
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