ocaml/otherlibs/unix/write.c

57 lines
1.8 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 <errno.h>
#include <string.h>
#include <mlvalues.h>
#include <memory.h>
#include <signals.h>
#include "unixsupport.h"
#ifndef EAGAIN
#define EAGAIN (-1)
#endif
#ifndef EWOULDBLOCK
#define EWOULDBLOCK (-1)
#endif
CAMLprim value unix_write(value fd, value buf, value vofs, value vlen)
{
long ofs, len, written;
int numbytes, ret;
char iobuf[UNIX_BUFFER_SIZE];
Begin_root (buf);
ofs = Long_val(vofs);
len = Long_val(vlen);
written = 0;
while (len > 0) {
numbytes = len > UNIX_BUFFER_SIZE ? UNIX_BUFFER_SIZE : len;
memmove (iobuf, &Byte(buf, ofs), numbytes);
enter_blocking_section();
ret = write(Int_val(fd), iobuf, numbytes);
leave_blocking_section();
if (ret == -1) {
if ((errno == EAGAIN || errno == EWOULDBLOCK) && written > 0) break;
uerror("write", Nothing);
}
written += ret;
ofs += ret;
len -= ret;
}
End_roots();
return Val_long(written);
}