examples/buttons/buttons_main.c - nuttx-apps - Git at Google

 /****************************************************************************
  * examples/buttons/buttons_main.c
  *
  *   Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  * 3. Neither the name NuttX nor the names of its contributors may be
  *    used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
  ****************************************************************************/

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

 #include <nuttx/config.h>

 #include <sys/ioctl.h>
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include <poll.h>
 #include <fcntl.h>
 #include <sched.h>
 #include <errno.h>

 #include <nuttx/input/buttons.h>

 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/

 #ifndef CONFIG_BUTTONS
 #  error "CONFIG_BUTTONS is not defined in the configuration"
 #endif

 #ifndef CONFIG_BUTTONS_NPOLLWAITERS
 #  define CONFIG_BUTTONS_NPOLLWAITERS 2
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_SIGNO
 #  define CONFIG_EXAMPLES_BUTTONS_SIGNO 13
 #endif

 #ifndef CONFIG_BUTTONS_POLL_DELAY
 #  define CONFIG_BUTTONS_POLL_DELAY 1000
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME0
 #  define CONFIG_EXAMPLES_BUTTONS_NAME0 "BUTTON0"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME1
 #  define CONFIG_EXAMPLES_BUTTONS_NAME1 "BUTTON1"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME2
 #  define CONFIG_EXAMPLES_BUTTONS_NAME2 "BUTTON2"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME3
 #  define CONFIG_EXAMPLES_BUTTONS_NAME3 "BUTTON3"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME4
 #  define CONFIG_EXAMPLES_BUTTONS_NAME4 "BUTTON4"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME5
 #  define CONFIG_EXAMPLES_BUTTONS_NAME5 "BUTTON5"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME6
 #  define CONFIG_EXAMPLES_BUTTONS_NAME6 "BUTTON6"
 #endif

 #ifndef CONFIG_EXAMPLES_BUTTONS_NAME7
 #  define CONFIG_EXAMPLES_BUTTONS_NAME7 "BUTTON7"
 #endif

 #define BUTTON_MAX 8

 #ifndef CONFIG_EXAMPLES_BUTTONS_QTD
 #  define CONFIG_EXAMPLES_BUTTONS_QTD BUTTON_MAX
 #endif

 #if CONFIG_EXAMPLES_BUTTONS_QTD > 8
 #  error "CONFIG_EXAMPLES_BUTTONS_QTD > 8"
 #endif

 /****************************************************************************
  * Private Data
  ****************************************************************************/

 #ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
 static const char button_name[CONFIG_EXAMPLES_BUTTONS_QTD][16] =
 {
   CONFIG_EXAMPLES_BUTTONS_NAME0
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 1
   , CONFIG_EXAMPLES_BUTTONS_NAME1
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 2
   , CONFIG_EXAMPLES_BUTTONS_NAME2
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 3
   , CONFIG_EXAMPLES_BUTTONS_NAME3
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 4
   , CONFIG_EXAMPLES_BUTTONS_NAME4
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 5
   , CONFIG_EXAMPLES_BUTTONS_NAME5
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 6
   , CONFIG_EXAMPLES_BUTTONS_NAME6
 #endif
 #if CONFIG_EXAMPLES_BUTTONS_QTD > 7
   , CONFIG_EXAMPLES_BUTTONS_NAME7
 #endif
 };
 #endif

 static bool g_button_daemon_started;

 /****************************************************************************
  * Private Functions
  ****************************************************************************/

 /****************************************************************************
  * Name: button_daemon
  ****************************************************************************/

 static int button_daemon(int argc, char *argv[])
 {
 #ifdef CONFIG_EXAMPLES_BUTTONS_POLL
   struct pollfd fds[CONFIG_BUTTONS_NPOLLWAITERS];
 #endif

 #ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
   struct btn_notify_s btnevents;
 #endif

   btn_buttonset_t supported;
   btn_buttonset_t sample = 0;

 #ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
   btn_buttonset_t oldsample = 0;
 #endif

   int ret;
   int fd;
   int i;

   UNUSED(i);

   /* Indicate that we are running */

   g_button_daemon_started = true;
   printf("button_daemon: Running\n");

   /* Open the BUTTON driver */

   printf("button_daemon: Opening %s\n", CONFIG_EXAMPLES_BUTTONS_DEVPATH);
   fd = open(CONFIG_EXAMPLES_BUTTONS_DEVPATH, O_RDONLY|O_NONBLOCK);
   if (fd < 0)
     {
       int errcode = errno;
       printf("button_daemon: ERROR: Failed to open %s: %d\n",
              CONFIG_EXAMPLES_BUTTONS_DEVPATH, errcode);
       goto errout;
     }

   /* Get the set of BUTTONs supported */

   ret = ioctl(fd, BTNIOC_SUPPORTED,
               (unsigned long)((uintptr_t)&supported));
   if (ret < 0)
     {
       int errcode = errno;
       printf("button_daemon: ERROR: ioctl(BTNIOC_SUPPORTED) failed: %d\n",
              errcode);
       goto errout_with_fd;
     }

   printf("button_daemon: Supported BUTTONs 0x%02x\n", (unsigned int)supported);

 #ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
   /* Define the notifications events */

   btnevents.bn_press   = supported;
   btnevents.bn_release = supported;

   btnevents.bn_event.sigev_notify = SIGEV_SIGNAL;
   btnevents.bn_event.sigev_signo  = CONFIG_EXAMPLES_BUTTONS_SIGNO;

   /* Register to receive a signal when buttons are pressed/released */

   ret = ioctl(fd, BTNIOC_REGISTER,
               (unsigned long)((uintptr_t)&btnevents));
   if (ret < 0)
     {
       int errcode = errno;
       printf("button_daemon: ERROR: ioctl(BTNIOC_SUPPORTED) failed: %d\n",
              errcode);
       goto errout_with_fd;
     }
 #endif

   /* Now loop forever, waiting BUTTONs events */

   for (; ; )
     {
 #ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
       struct siginfo value;
       sigset_t set;
 #endif

 #ifdef CONFIG_EXAMPLES_BUTTONS_POLL
       bool timeout;
       bool pollin;
       int nbytes;
 #endif

 #ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
       /* Wait for a signal */

       sigemptyset(&set);
       sigaddset(&set, CONFIG_EXAMPLES_BUTTONS_SIGNO);
       ret = sigwaitinfo(&set, &value);
       if (ret < 0)
         {
           int errcode = errno;
           printf("button_daemon: ERROR: sigwaitinfo() failed: %d\n", errcode);
           goto errout_with_fd;
         }

       sample = (btn_buttonset_t)value.si_value.sival_int;
 #endif

 #ifdef CONFIG_EXAMPLES_BUTTONS_POLL
       /* Prepare the File Descriptor for poll */

       memset(fds, 0, sizeof(struct pollfd)*CONFIG_BUTTONS_NPOLLWAITERS);

       fds[0].fd      = fd;
       fds[0].events  = POLLIN;

       timeout        = false;
       pollin         = false;

       ret = poll(fds, CONFIG_BUTTONS_NPOLLWAITERS, CONFIG_BUTTONS_POLL_DELAY);

       printf("\nbutton_daemon: poll returned: %d\n", ret);
       if (ret < 0)
         {
           int errcode = errno;
           printf("button_daemon: ERROR poll failed: %d\n", errcode);
         }
       else if (ret == 0)
         {
           printf("button_daemon: Timeout\n");
           timeout = true;
         }
       else if (ret > CONFIG_BUTTONS_NPOLLWAITERS)
         {
           printf("button_daemon: ERROR poll reported: %d\n", errno);
         }
       else
         {
           pollin = true;
         }

       /* In any event, read until the pipe is empty */

       for (i = 0; i < CONFIG_BUTTONS_NPOLLWAITERS; i++)
         {
           do
             {
               nbytes = read(fds[i].fd, (void *)&sample,
                             sizeof(btn_buttonset_t));

               if (nbytes <= 0)
                 {
                   if (nbytes == 0 || errno == EAGAIN)
                     {
                       if ((fds[i].revents & POLLIN) != 0)
                         {
                           printf("button_daemon: ERROR no read data[%d]\n", i);
                         }
                     }
                   else if (errno != EINTR)
                     {
                       printf("button_daemon: read[%d] failed: %d\n", i, errno);
                     }

                   nbytes = 0;
                 }
               else
                 {
                   if (timeout)
                     {
                       printf("button_daemon: ERROR? Poll timeout, but data read[%d]\n", i);
                       printf("               (might just be a race condition)\n");
                     }
                 }

               /* Suppress error report if no read data on the next time through */

               fds[i].revents = 0;
             }
           while (nbytes > 0);
         }
 #endif

 #ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
       /* Print name of all pressed/release button */

       for (i = 0; i < CONFIG_EXAMPLES_BUTTONS_QTD; i++)
         {
           if ((sample & (1 << i)) && !(oldsample & (1 << i)))
             {
               printf("%s was pressed\n", button_name[i]);
             }

           if (!(sample & (1 << i)) && (oldsample & (1 << i)))
             {
               printf("%s was released\n", button_name[i]);
             }
         }

       oldsample = sample;
 #else
       printf("Sample = %d\n", sample);
 #endif

       /* Make sure that everything is displayed */

       fflush(stdout);

       usleep(1000);
     }

 errout_with_fd:
   close(fd);

 errout:
   g_button_daemon_started = false;

   printf("button_daemon: Terminating\n");
   return EXIT_FAILURE;
 }

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

 /****************************************************************************
  * buttons_main
  ****************************************************************************/

 int main(int argc, FAR char *argv[])
 {
   int ret;

   printf("buttons_main: Starting the button_daemon\n");
   if (g_button_daemon_started)
     {
       printf("buttons_main: button_daemon already running\n");
       return EXIT_SUCCESS;
     }

   ret = task_create("button_daemon", CONFIG_EXAMPLES_BUTTONS_PRIORITY,
                     CONFIG_EXAMPLES_BUTTONS_STACKSIZE, button_daemon,
                     NULL);
   if (ret < 0)
     {
       int errcode = errno;
       printf("buttons_main: ERROR: Failed to start button_daemon: %d\n",
              errcode);
       return EXIT_FAILURE;
     }

   printf("buttons_main: button_daemon started\n");
   return EXIT_SUCCESS;
 }
	/****************************************************************************
	* examples/buttons/buttons_main.c
	*
	* Copyright (C) 2016-2017 Gregory Nutt. All rights reserved.
	* Author: Gregory Nutt <gnutt@nuttx.org>
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	* 3. Neither the name NuttX nor the names of its contributors may be
	* used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
	* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
	* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
	* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
	* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
	* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	* POSSIBILITY OF SUCH DAMAGE.
	*
	****************************************************************************/

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

	#include <nuttx/config.h>

	#include <sys/ioctl.h>
	#include <stdbool.h>
	#include <stdlib.h>
	#include <string.h>
	#include <stdio.h>
	#include <poll.h>
	#include <fcntl.h>
	#include <sched.h>
	#include <errno.h>

	#include <nuttx/input/buttons.h>

	/****************************************************************************
	* Pre-processor Definitions
	****************************************************************************/

	#ifndef CONFIG_BUTTONS
	# error "CONFIG_BUTTONS is not defined in the configuration"
	#endif

	#ifndef CONFIG_BUTTONS_NPOLLWAITERS
	# define CONFIG_BUTTONS_NPOLLWAITERS 2
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_SIGNO
	# define CONFIG_EXAMPLES_BUTTONS_SIGNO 13
	#endif

	#ifndef CONFIG_BUTTONS_POLL_DELAY
	# define CONFIG_BUTTONS_POLL_DELAY 1000
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME0
	# define CONFIG_EXAMPLES_BUTTONS_NAME0 "BUTTON0"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME1
	# define CONFIG_EXAMPLES_BUTTONS_NAME1 "BUTTON1"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME2
	# define CONFIG_EXAMPLES_BUTTONS_NAME2 "BUTTON2"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME3
	# define CONFIG_EXAMPLES_BUTTONS_NAME3 "BUTTON3"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME4
	# define CONFIG_EXAMPLES_BUTTONS_NAME4 "BUTTON4"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME5
	# define CONFIG_EXAMPLES_BUTTONS_NAME5 "BUTTON5"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME6
	# define CONFIG_EXAMPLES_BUTTONS_NAME6 "BUTTON6"
	#endif

	#ifndef CONFIG_EXAMPLES_BUTTONS_NAME7
	# define CONFIG_EXAMPLES_BUTTONS_NAME7 "BUTTON7"
	#endif

	#define BUTTON_MAX 8

	#ifndef CONFIG_EXAMPLES_BUTTONS_QTD
	# define CONFIG_EXAMPLES_BUTTONS_QTD BUTTON_MAX
	#endif

	#if CONFIG_EXAMPLES_BUTTONS_QTD > 8
	# error "CONFIG_EXAMPLES_BUTTONS_QTD > 8"
	#endif

	/****************************************************************************
	* Private Data
	****************************************************************************/

	#ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
	static const char button_name[CONFIG_EXAMPLES_BUTTONS_QTD][16] =
	{
	CONFIG_EXAMPLES_BUTTONS_NAME0
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 1
	, CONFIG_EXAMPLES_BUTTONS_NAME1
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 2
	, CONFIG_EXAMPLES_BUTTONS_NAME2
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 3
	, CONFIG_EXAMPLES_BUTTONS_NAME3
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 4
	, CONFIG_EXAMPLES_BUTTONS_NAME4
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 5
	, CONFIG_EXAMPLES_BUTTONS_NAME5
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 6
	, CONFIG_EXAMPLES_BUTTONS_NAME6
	#endif
	#if CONFIG_EXAMPLES_BUTTONS_QTD > 7
	, CONFIG_EXAMPLES_BUTTONS_NAME7
	#endif
	};
	#endif

	static bool g_button_daemon_started;

	/****************************************************************************
	* Private Functions
	****************************************************************************/

	/****************************************************************************
	* Name: button_daemon
	****************************************************************************/

	static int button_daemon(int argc, char *argv[])
	{
	#ifdef CONFIG_EXAMPLES_BUTTONS_POLL
	struct pollfd fds[CONFIG_BUTTONS_NPOLLWAITERS];
	#endif

	#ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
	struct btn_notify_s btnevents;
	#endif

	btn_buttonset_t supported;
	btn_buttonset_t sample = 0;

	#ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
	btn_buttonset_t oldsample = 0;
	#endif

	int ret;
	int fd;
	int i;

	UNUSED(i);

	/* Indicate that we are running */

	g_button_daemon_started = true;
	printf("button_daemon: Running\n");

	/* Open the BUTTON driver */

	printf("button_daemon: Opening %s\n", CONFIG_EXAMPLES_BUTTONS_DEVPATH);
	fd = open(CONFIG_EXAMPLES_BUTTONS_DEVPATH, O_RDONLY\|O_NONBLOCK);
	if (fd < 0)
	{
	int errcode = errno;
	printf("button_daemon: ERROR: Failed to open %s: %d\n",
	CONFIG_EXAMPLES_BUTTONS_DEVPATH, errcode);
	goto errout;
	}

	/* Get the set of BUTTONs supported */

	ret = ioctl(fd, BTNIOC_SUPPORTED,
	(unsigned long)((uintptr_t)&supported));
	if (ret < 0)
	{
	int errcode = errno;
	printf("button_daemon: ERROR: ioctl(BTNIOC_SUPPORTED) failed: %d\n",
	errcode);
	goto errout_with_fd;
	}

	printf("button_daemon: Supported BUTTONs 0x%02x\n", (unsigned int)supported);

	#ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
	/* Define the notifications events */

	btnevents.bn_press = supported;
	btnevents.bn_release = supported;

	btnevents.bn_event.sigev_notify = SIGEV_SIGNAL;
	btnevents.bn_event.sigev_signo = CONFIG_EXAMPLES_BUTTONS_SIGNO;

	/* Register to receive a signal when buttons are pressed/released */

	ret = ioctl(fd, BTNIOC_REGISTER,
	(unsigned long)((uintptr_t)&btnevents));
	if (ret < 0)
	{
	int errcode = errno;
	printf("button_daemon: ERROR: ioctl(BTNIOC_SUPPORTED) failed: %d\n",
	errcode);
	goto errout_with_fd;
	}
	#endif

	/* Now loop forever, waiting BUTTONs events */

	for (; ; )
	{
	#ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
	struct siginfo value;
	sigset_t set;
	#endif

	#ifdef CONFIG_EXAMPLES_BUTTONS_POLL
	bool timeout;
	bool pollin;
	int nbytes;
	#endif

	#ifdef CONFIG_EXAMPLES_BUTTONS_SIGNAL
	/* Wait for a signal */

	sigemptyset(&set);
	sigaddset(&set, CONFIG_EXAMPLES_BUTTONS_SIGNO);
	ret = sigwaitinfo(&set, &value);
	if (ret < 0)
	{
	int errcode = errno;
	printf("button_daemon: ERROR: sigwaitinfo() failed: %d\n", errcode);
	goto errout_with_fd;
	}

	sample = (btn_buttonset_t)value.si_value.sival_int;
	#endif

	#ifdef CONFIG_EXAMPLES_BUTTONS_POLL
	/* Prepare the File Descriptor for poll */

	memset(fds, 0, sizeof(struct pollfd)*CONFIG_BUTTONS_NPOLLWAITERS);

	fds[0].fd = fd;
	fds[0].events = POLLIN;

	timeout = false;
	pollin = false;

	ret = poll(fds, CONFIG_BUTTONS_NPOLLWAITERS, CONFIG_BUTTONS_POLL_DELAY);

	printf("\nbutton_daemon: poll returned: %d\n", ret);
	if (ret < 0)
	{
	int errcode = errno;
	printf("button_daemon: ERROR poll failed: %d\n", errcode);
	}
	else if (ret == 0)
	{
	printf("button_daemon: Timeout\n");
	timeout = true;
	}
	else if (ret > CONFIG_BUTTONS_NPOLLWAITERS)
	{
	printf("button_daemon: ERROR poll reported: %d\n", errno);
	}
	else
	{
	pollin = true;
	}

	/* In any event, read until the pipe is empty */

	for (i = 0; i < CONFIG_BUTTONS_NPOLLWAITERS; i++)
	{
	do
	{
	nbytes = read(fds[i].fd, (void *)&sample,
	sizeof(btn_buttonset_t));

	if (nbytes <= 0)
	{
	if (nbytes == 0 \|\| errno == EAGAIN)
	{
	if ((fds[i].revents & POLLIN) != 0)
	{
	printf("button_daemon: ERROR no read data[%d]\n", i);
	}
	}
	else if (errno != EINTR)
	{
	printf("button_daemon: read[%d] failed: %d\n", i, errno);
	}

	nbytes = 0;
	}
	else
	{
	if (timeout)
	{
	printf("button_daemon: ERROR? Poll timeout, but data read[%d]\n", i);
	printf(" (might just be a race condition)\n");
	}
	}

	/* Suppress error report if no read data on the next time through */

	fds[i].revents = 0;
	}
	while (nbytes > 0);
	}
	#endif

	#ifdef CONFIG_EXAMPLES_BUTTONS_NAMES
	/* Print name of all pressed/release button */

	for (i = 0; i < CONFIG_EXAMPLES_BUTTONS_QTD; i++)
	{
	if ((sample & (1 << i)) && !(oldsample & (1 << i)))
	{
	printf("%s was pressed\n", button_name[i]);
	}

	if (!(sample & (1 << i)) && (oldsample & (1 << i)))
	{
	printf("%s was released\n", button_name[i]);
	}
	}

	oldsample = sample;
	#else
	printf("Sample = %d\n", sample);
	#endif

	/* Make sure that everything is displayed */

	fflush(stdout);

	usleep(1000);
	}

	errout_with_fd:
	close(fd);

	errout:
	g_button_daemon_started = false;

	printf("button_daemon: Terminating\n");
	return EXIT_FAILURE;
	}

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

	/****************************************************************************
	* buttons_main
	****************************************************************************/

	int main(int argc, FAR char *argv[])
	{
	int ret;

	printf("buttons_main: Starting the button_daemon\n");
	if (g_button_daemon_started)
	{
	printf("buttons_main: button_daemon already running\n");
	return EXIT_SUCCESS;
	}

	ret = task_create("button_daemon", CONFIG_EXAMPLES_BUTTONS_PRIORITY,
	CONFIG_EXAMPLES_BUTTONS_STACKSIZE, button_daemon,
	NULL);
	if (ret < 0)
	{
	int errcode = errno;
	printf("buttons_main: ERROR: Failed to start button_daemon: %d\n",
	errcode);
	return EXIT_FAILURE;
	}

	printf("buttons_main: button_daemon started\n");
	return EXIT_SUCCESS;
	}