Re: adjusting the length of an SV?

[mjd-perl-pm@plover.com]

> On Tue, Jun 12, 2001 at 02:40:15PM -0400, Kyle R . Burton wrote:
> > > Without actualy using something like sv_setpv, sv_setpvn, or sv_setsv,
> > > can I just null out one of the chars, and then adjust the length that
> > > Perl has assoicated with the SV?
> > > 
> > > I can't seem to find any macros or functions in perlguts or perlxs that
> > > shows how to adjust this length.
> > 
> > Sorry, I found it in perlguts:
> > 
> >   SvCUR_set(SV*,I32)
> 
> 
> Note that you should not null out characters - Perl has 8-bit clean strings,
> and a null is a valid character.

In this case you are mistaken.  According to perlguts:

       All SVs that contain strings should be terminated with a NUL
       character.  If it is not NUL-terminated there is a risk of core
       dumps and corruptions from code which passes the string to C
       functions or system calls which expect a NUL-terminated string.
       Perl's own functions typically add a trailing NUL for this
       reason.

Since Kyle is shortening the string with SvCUR_set, he should insert a
NUL character after the new final character of the string.

**Majordomo list services provided by PANIX <URL:http://www.panix.com>**
**To Unsubscribe, send "unsubscribe phl" to majordomo@lists.pm.org**