93 lines
3.1 KiB
C
93 lines
3.1 KiB
C
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/****************************************************************************
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* examples/ostest/dev_null.c
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*
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* Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
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* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name NuttX nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <stdio.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include "ostest.h"
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/****************************************************************************
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* Private Data
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****************************************************************************/
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#if CONFIG_NFILE_DESCRIPTORS > 0
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static FAR char buffer[1024];
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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int dev_null(void)
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{
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int nbytes;
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int fd;
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fd = open("/dev/null", O_RDWR);
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if (fd < 0)
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{
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printf("dev_null: ERROR Failed to open /dev/null\n");
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return -1;
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}
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nbytes = read(fd, buffer, 1024);
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if (nbytes < 0)
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{
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printf("dev_null: ERROR Failed to read from /dev/null\n");
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close(fd);
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return -1;
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}
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printf("dev_null: Read %d bytes from /dev/null\n", nbytes);
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nbytes = write(fd, buffer, 1024);
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if (nbytes < 0)
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{
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printf("dev_null: ERROR Failed to write to /dev/null\n");
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close(fd);
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return -1;
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}
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printf("dev_null: Wrote %d bytes to /dev/null\n", nbytes);
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close(fd);
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return 0;
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}
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#endif /*CONFIG_NFILE_DESCRIPTORS */
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