Re: Portable way of finding libc, unbuffered reads

[Clinton A. Pierce]

At 11:55 PM 6/20/2003 +0200, Jens Rieks wrote:
> (Which in itself tickles and scares the bejesus out of me.)  Is there a
> good way of finding the standard C library on a Unix system other than
> hard-wiring it in like this?
Yes. Parrot is linked with the standard C library. You can get a handle for
the own executable by passing a NULL pointer to dlopen. You can also use this
handle to call libc functions.
You can not pass a NULL pointer to loadlib at the moment, this small hacks
"converts" an empty string to a NULL pointer to pass it to Parror_dlopen:
  const char * s = 0;

  if( $2->strlen != 0 ) {
    s = string_to_cstring(interpreter, ($2));
  }
  p = Parrot_dlopen(s);
With this hack, the following code will work:

        loadlib P1, ""
        dlfunc P0, P1, "system", "it"
        set I0, 1
        set S5, "ls"
        invoke
        end
A very cool hack, indeed.  :)

It's gonna need a little work though.  On Win32 Parrot_dlopen is a 
passthrough to LoadLibrary() which, as far as I can tell, doesn't have the 
same behavior for this case.  *But* it seems as though if you can find 
parrot's name (imcc.exe, parrot.exe, etc...) and pass *that* to loadlib it 
should work fine.  Maybe.  More testing required.

On my linux box (which was the issue...) it seems fine though.  Whee.

Thanks!