doh! I suspected they were tied handles, but I figured PerlIO_* would handle that. Otherwise, you end up with the following:

/* Returns TRUE on success. Sets errno on error. */
int my_print(SV* sv) {
    GV* const   gv = PL_defoutgv;
    IO*         io;
    MAGIC*      mg;
    PerlIO*     fp;
    int         success;
    const char* buf;
    STRLEN      to_write;

    io = GvIO(gv);
    if (!io && GvEGV(gv)) {
        io = GvIO(GvEGV(gv));
    }
    if (!io) {
        return FALSE;
    }

    mg = SvTIED_mg((SV*)io, PERL_MAGIC_tiedscalar);
    if (mg) {
        dSP;

        ENTER;
        SAVETMPS;

        PUSHMARK(SP);
        XPUSHs(SvTIED_obj((SV*)io, mg));
        XPUSHs(sv);
        PUTBACK;

        call_method("PRINT", G_SCALAR);

        SPAGAIN;
        success = 0 != POPi;
        PUTBACK;

        FREETMPS;
        LEAVE;

        return success;
    }

    fp = IoOFP(io);
    if (!fp) {
        return FALSE;
    }

    buf = SvPV(sv, to_write);
    while (to_write > 0) {
        int written = PerlIO_write(fp, buf, to_write);
        if (written < 0) {
            return FALSE;
        }

        buf      += written;
        to_write -= written;
    }

    return TRUE;
}
[download]

(Untested. Based in part on code from pp_print, the function that implements the print operator.)

That writes the the currently selected handle. It shouldn't need much work to work with any handle. Why isn't this already supplied by Perl? Or did I overlook it?

Update: Arg! It's not complete. There are encoding issues.

If s is assumed to be bytes,

• If PerlIO_isutf8(fp) is true, s needs to be converted to UTF-8 (i.e. perform an utf8::upgrade).

If s is assumed to be UTF-8,

• If PerlIO_isutf8(fp) is false and the bytes pragma isn't in effect, s needs to be converted to iso-8859-1 (i.e perform an utf8::downgrade).

Does calling CORE::print work from XS? That would be simpler! If it doesn't work, it would still be simpler to write a Perl wrapper for print and call that.

Update: Fixed compilation errors. Didn't address the problem mentioned above.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.