From: Mark Probert <probertm@...>
Date: 2005-07-27T08:15:10+09:00
Subject: redirecting stdout in an extension

Hi ..

Any ideas on how to redirect stdout in an extension and then revert it
back to its default behaviour?  freopen() redirects, though I am not
sure of returning to normal programming.

So,

VALUE rb_dump(VALUE self, VALUE o_name)
{
    VALUE   rval;       /* our result */
    VALUE   fname;      /* holds the filename */
    
    fname = StringValue(o_name);
    
    /* redirect stdout */
    freopen("a.xml", "w+", stdout);
    if (foo_dump(STR2CSTR(fname)) == -1) {
        rval = Qnil;
    } else {
        rval = Qtrue;
    }
    fclose(stdout);  /* bad!!! want to go back to fd 1 */
    return rval;
}

BTW, I have no way of modifying the call to foo_dump() to take a file
handle.  It just splurts out to stdout.

Many thanks, 

-- 
-mark.  (probertm at acm dot org)