incubator-nuttx/libs/libc/stdio/lib_fgetpos.c

73 lines
2.3 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_fgetpos.c
*
* 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;
}