... modifying the buffer does not shrink it

So what does SvLEN tell us about the buffer ?
According to perlapi documentation: 
"SvLEN"
    Returns the size of the string buffer in the SV, not including any
    part attributable to "SvOOK". See "SvCUR".

[download]
Now, I don't understand the reference to "SvOOK" and "SvCUR", but the bit that says "Returns the size of the string buffer in the SV" means (to me) that if the value of LEN (ie SvLEN) has been reduced, then size of the buffer has been reduced - ie the buffer has been shrunk.
Not so ?

Cheers,
Rob

In reply to Re^4: [XS] sv_setpv change in behaviour with perl-5.42.0 and later by syphilis
in thread [XS] sv_setpv change in behaviour with perl-5.42.0 and later by syphilis

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