ocaml/otherlibs/win32unix/read.c

43 lines
1.6 KiB
C

/***********************************************************************/
/* */
/* Objective Caml */
/* */
/* Xavier Leroy, 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. */
/* */
/***********************************************************************/
/* $Id$ */
#include <string.h>
#include <mlvalues.h>
#include <memory.h>
#include <signals.h>
#include "unixsupport.h"
CAMLprim value unix_read(value fd, value buf, value ofs, value len)
{
DWORD numbytes, numread;
BOOL ret;
char iobuf[UNIX_BUFFER_SIZE];
HANDLE h = Handle_val(fd);
Begin_root (buf);
numbytes = Long_val(len);
if (numbytes > UNIX_BUFFER_SIZE) numbytes = UNIX_BUFFER_SIZE;
enter_blocking_section();
ret = ReadFile(h, iobuf, numbytes, &numread, NULL);
leave_blocking_section();
if (! ret) {
win32_maperr(GetLastError());
uerror("read", Nothing);
}
memmove (&Byte(buf, Long_val(ofs)), iobuf, numread);
End_roots();
return Val_int(numread);
}