ocaml/otherlibs/win32unix/pipe.c

/***********************************************************************/
/*                                                                     */
/*                                OCaml                                */
/*                                                                     */
/*  Xavier Leroy and Pascal Cuoq, projet Cristal, INRIA Rocquencourt   */
/*                                                                     */
/*  Copyright 1996 Institut National de Recherche en Informatique et   */
/*  en Automatique.  All rights reserved.  This file is distributed    */
/*  under the terms of the GNU Library General Public License, with    */
/*  the special exception on linking described in file ../../LICENSE.  */
/*                                                                     */
/***********************************************************************/

#include <mlvalues.h>
#include <memory.h>
#include <alloc.h>
#include "unixsupport.h"
#include <fcntl.h>

/* PR#4749: pick a size that matches that of I/O buffers */
#define SIZEBUF 4096

CAMLprim value unix_pipe(value unit)
{
  SECURITY_ATTRIBUTES attr;
  HANDLE readh, writeh;
  value readfd = Val_unit, writefd = Val_unit, res;

  attr.nLength = sizeof(attr);
  attr.lpSecurityDescriptor = NULL;
  attr.bInheritHandle = TRUE;
  if (! CreatePipe(&readh, &writeh, &attr, SIZEBUF)) {
    win32_maperr(GetLastError());
    uerror("pipe", Nothing);
  }
  Begin_roots2(readfd, writefd)
    readfd = win_alloc_handle(readh);
    writefd = win_alloc_handle(writeh);
    res = alloc_small(2, 0);
    Field(res, 0) = readfd;
    Field(res, 1) = writefd;
  End_roots();
  return res;
}