Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??
Hi,
In response to XS on 64-bit: Warning from sv_vsetpvf call almut posted some code that led me to the following Inline::C script:
use warnings; use Inline C => <<'EOC'; void vatest__(char* format, va_list* args) { char buf[1024]; vsprintf(buf, format, *args); errno = 0; // "Success" perror(buf); } void vatest_(char* format, va_list* args) { vatest__(format, args); } void vatest(char* format, ...) { va_list args; va_start (args, format); vatest_(format, &args); va_end (args); } SV * foo () { char* msg0 = "vatest"; char* msg1 = "foo"; char* msg2 = "bar"; double d = 12.345; unsigned long l = 1234567890; vatest("%s %s", msg0, msg1); vatest("%s %s %s %u %f", msg0, msg1, msg2, l, d); return newSViv(0); } EOC foo();
which outputs (on Win32):
vatest foo: No error vatest foo bar 1234567890 12.345000: No error
which is correct and as expected.

But then I got to wondering whether vatest() could be called directly from perl - ie, instead of having the perl section of the above script do foo(); have it do something like vatest('%s %s', 'foo', 'bar'); which would output foo bar: No error.
But, of course, that doesn't work - and I'm unable to find a way of making it work.

So, is there a way of accessing the XSub vatest() directly from perl (with either XS or Inline::C) ? I'm pretty sure there isn't ... but I'm so often wrong. Faik, there could well be some clever typemapping (or other technique) that makes it possible.

Cheers,
Rob

In reply to XS/Inline::C and ellipsis syntax by syphilis

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • 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! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, 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, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • Outside of code tags, you may need to use entities for some characters:
            For:     Use:
    & &amp;
    < &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.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others examining the Monastery: (7)
    As of 2014-11-26 00:26 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      My preferred Perl binaries come from:














      Results (160 votes), past polls