77f0bea7创建于 4月21日历史提交
/****************************************************************************
 * libs/libc/stdio/lib_fgetpos.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdio.h>
#include <errno.h>

#include "libc.h"

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: fgetpos
 *
 * Description:
 *   fgetpos() function is an alternate interfaces equivalent to ftell().
 *   It gets the current value of the file offset and store it in the
 *   location referenced by pos.  On some non-UNIX systems an fpos_t object
 *   may be a complex object and fsetpos may be the only way to portably
 *   reposition a stream.
 *
 * Returned Value:
 *   Zero on success; -1 on failure with errno set appropriately.
 *
 ****************************************************************************/

int fgetpos(FAR FILE *stream, FAR fpos_t *pos)
{
  off_t position;

#ifdef CONFIG_DEBUG_FEATURES
  if (!stream || !pos)
    {
      set_errno(EINVAL);
      return ERROR;
    }
#endif

  position = ftello(stream);
  if (position == (off_t)-1)
    {
      return ERROR;
    }

  *pos = position;
  return OK;
}