Re: Configurable IO buffersize?

This *ought* to work , untested, but I just copy/pasted the relevant bits from PerlIOBuf_get_base :) Edit perl-5.15.1/dist/IO/IO.xs

void
setbuf(handle, ...)
    OutputStream    handle
    CODE:
    if (handle)
#ifdef PERLIO_IS_STDIO
        {
        char *buf = items == 2 && SvPOK(ST(1)) ?
          sv_grow(ST(1), BUFSIZ) : 0;
        setbuf(handle, buf);
    }
#else
    {    /* not_here("IO::Handle::setbuf"); */
        
        PerlIOBuf * const b = PerlIOSelf(f, PerlIOBuf);
        PERL_UNUSED_CONTEXT;
        if(items == 2 && SvPOK(ST(1)) )
        {
            b->bufsiz = SvLEN(ST(1));
            Newxz(b->buf, b->bufsiz , STDCHAR);
        }
    }
#endif
[download]

The transformation to setvbuf would be similar, but, i'll let you work out the logic :)

Comment on Re: Configurable IO buffersize? Download Code

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Re^2: Configurable IO buffersize? by BrowserUk (Patriarch) on Aug 02, 2011 at 02:43 UTC
Thank you kind Sir. Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^3: Configurable IO buffersize? by Anonymous Monk on Aug 02, 2011 at 11:15 UTC
Ok, now I've tested it, it works, the concept is proved, but there are some issues, like using :raw causes PerlIO to croak -- probably something about XS I'm doing wrong :) Read more... (9 kB) I used ->getbufsiz to test if ->setbuf had effect, because Devel::Peek/Data::Peek was no help with handles, and trying to parse perliol.h with Convert::Binary::C wasn't happening This definitely needs official support Cheers	[reply] [d/l]
Re^4: Configurable IO buffersize? by Anonymous Monk on Aug 02, 2011 at 13:44 UTC
Some more testing, none of these behave like :raw, they seem to "work" `Fudge( __FILE__ , ':raw:perlio:encoding(UTF-16LE):crlf', 6 ); Fudge( __FILE__ , ':raw:perlio:encoding(UTF-16LE):utf8', 6 ); Fudge( __FILE__ , ':raw:perlio', 7666 ); Fudge( __FILE__ , ':raw:win32', 6 ); Fudge( __FILE__ , ':win32', 6 );` [download] Though now its obvious that the :raw issue is probably pointer arithmetic related (and/or related to Chicanery Needed to Handle Unicode Text on Microsoft Windows) It remains, that setting a lower length than previous buffer length, doesn't change the length, only setting a higher one changes it I reiterate, this definitely needs official support :)	[reply] [d/l]
Re^4: Configurable IO buffersize? by BrowserUk (Patriarch) on Aug 02, 2011 at 11:21 UTC
here are some issues, like using :raw causes PerlIO to croak Doesn't `:raw` disable buffering? Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^5: Configurable IO buffersize? by Anonymous Monk on Aug 02, 2011 at 12:27 UTC
Re^3: Configurable IO buffersize? by Anonymous Monk on Aug 02, 2011 at 02:50 UTC
Bah, typo (f not handle), still untested :) `void setbuf(handle, ...) OutputStream handle CODE: if (handle) #ifdef PERLIO_IS_STDIO { char buf = items == 2 && SvPOK(ST(1)) ? sv_grow(ST(1), BUFSIZ) : 0; setbuf(handle, buf); } #else { / not_here("IO::Handle::setbuf"); / PerlIOBuf const b = PerlIOSelf( handle, PerlIOBuf); PERL_UNUSED_CONTEXT; if(items == 2 && SvPOK(ST(1)) ) { b->bufsiz = SvLEN(ST(1)); Newxz(b->buf, b->bufsiz , STDCHAR); } } #endif` [download]	[reply] [d/l]