Re: How big is an array?

[mjd-perl-pm@plover.com]

> mjd-perl-pm@plover.com writes:
>  [...]
>  > 
>  > So for example the string "BLARF" probably takes about 30 bytes.  (24
>  > overhead plus 6 for "BLARF\0")
> 
> Perl uses null-terminated strings internally?   How odd.  

It doesn't require the null-termination.  It's for easier
compatibility with C extensions.  Perl itself uses counted-length
strings, and stores the string's length (not including the extra
null).

> How, then, is a string with embedded NUL characters represented?

"blarf" is stored as

        length 5
        "barf\0"

"I\0like\0pie" is stored as

        length 10
        "I\0like\0pie\0"

Perl only pays attention to the length count, never to the null.

here's what the manual says about it:  

       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.  Nevertheless, you should be very careful when you pass
       a string stored in an SV to a C function or system call.

        (perlguts)

Hope this helps.
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