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explain_timerfd_create(3)  Library Functions Manual  explain_timerfd_create(3)

NAME
       explain_timerfd_create -	explain	timerfd_create(2) errors

SYNOPSIS
       #include	<libexplain/timerfd_create.h>
       const char *explain_timerfd_create(int clockid, int flags);
       const char *explain_errno_timerfd_create(int errnum, int	clockid, int
       flags);
       void explain_message_timerfd_create(char	*message, int message_size,
       int clockid, int	flags);
       void explain_message_errno_timerfd_create(char *message,	int mes-
       sage_size, int errnum, int clockid, int flags);

DESCRIPTION
       These functions may be used to obtain explanations for errors  returned
       by the timerfd_create(2)	system call.

   explain_timerfd_create
       const char *explain_timerfd_create(int clockid, int flags);

       The explain_timerfd_create function is used to obtain an	explanation of
       an error	returned by the	timerfd_create(2) system call. The  least  the
       message	will  contain  is the value of strerror(errno),	but usually it
       will do much better, and	indicate the underlying	cause in more detail.

       The errno global	variable will be used to obtain	the error value	to  be
       decoded.

       clockid The  original  clockid,	exactly	 as passed to the timerfd_cre-
	       ate(2) system call.

       flags   The original flags, exactly as passed to	the  timerfd_create(2)
	       system call.

       Returns:
	       The message explaining the error. This message buffer is	shared
	       by all libexplain functions which do not	 supply	 a  buffer  in
	       their argument list.  This will be overwritten by the next call
	       to any libexplain function which	shares this buffer,  including
	       other threads.

       Note: This function is not thread safe, because it shares a return buf-
       fer across all threads, and many	other functions	in this	library.

       Example:	This function is intended to be	used in	a fashion  similar  to
       the following example:
	      int result = timerfd_create(clockid, flags);
	      if (result < 0)
	      {
		  fprintf(stderr, "%s\n", explain_timerfd_create(clockid,
		  flags));
		  exit(EXIT_FAILURE);
	      }

       The  above  code	 example  is  available	 pre-packaged	as   the   ex-
       plain_timerfd_create_or_die(3) function.

   explain_errno_timerfd_create
       const char *explain_errno_timerfd_create(int errnum, int	clockid, int
       flags);

       The explain_errno_timerfd_create	function is used to obtain an explana-
       tion  of	 an  error  returned by	the timerfd_create(2) system call. The
       least the message will contain is the  value  of	 strerror(errno),  but
       usually	it  will  do much better, and indicate the underlying cause in
       more detail.

       errnum  The error value to be decoded, usually obtained from the	 errno
	       global  variable	 just  before this function is called. This is
	       necessary if you	need to	call any code between the system  call
	       to  be explained	and this function, because many	libc functions
	       will alter the value of errno.

       clockid The original clockid, exactly as	 passed	 to  the  timerfd_cre-
	       ate(2) system call.

       flags   The  original flags, exactly as passed to the timerfd_create(2)
	       system call.

       Returns:
	       The message explaining the error. This message buffer is	shared
	       by  all	libexplain  functions  which do	not supply a buffer in
	       their argument list.  This will be overwritten by the next call
	       to  any libexplain function which shares	this buffer, including
	       other threads.

       Note: This function is not thread safe, because it shares a return buf-
       fer across all threads, and many	other functions	in this	library.

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      int result = timerfd_create(clockid, flags);
	      if (result < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_timerfd_create(err,
		  clockid, flags));
		  exit(EXIT_FAILURE);
	      }

       The   above   code   example  is	 available  pre-packaged  as  the  ex-
       plain_timerfd_create_or_die(3) function.

   explain_message_timerfd_create
       void explain_message_timerfd_create(char	*message, int message_size,
       int clockid, int	flags);

       The explain_message_timerfd_create function is used to obtain an	expla-
       nation of an error returned by the timerfd_create(2) system  call.  The
       least  the  message  will  contain is the value of strerror(errno), but
       usually it will do much better, and indicate the	 underlying  cause  in
       more detail.

       The  errno global variable will be used to obtain the error value to be
       decoded.

       message The location in which to	store the returned message. If a suit-
	       able message return buffer is supplied, this function is	thread
	       safe.

       message_size
	       The size	in bytes of the	location in which  to  store  the  re-
	       turned message.

       clockid The  original  clockid,	exactly	 as passed to the timerfd_cre-
	       ate(2) system call.

       flags   The original flags, exactly as passed to	the  timerfd_create(2)
	       system call.

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      int result = timerfd_create(clockid, flags);
	      if (result < 0)
	      {
		  char message[3000];
		  explain_message_timerfd_create(message, sizeof(message),
		  clockid, flags);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       The   above   code   example  is	 available  pre-packaged  as  the  ex-
       plain_timerfd_create_or_die(3) function.

   explain_message_errno_timerfd_create
       void explain_message_errno_timerfd_create(char *message,	int mes-
       sage_size, int errnum, int clockid, int flags);

       The  explain_message_errno_timerfd_create function is used to obtain an
       explanation of an error returned	by the timerfd_create(2) system	 call.
       The least the message will contain is the value of strerror(errno), but
       usually it will do much better, and indicate the	 underlying  cause  in
       more detail.

       message The location in which to	store the returned message. If a suit-
	       able message return buffer is supplied, this function is	thread
	       safe.

       message_size
	       The  size  in  bytes  of	the location in	which to store the re-
	       turned message.

       errnum  The error value to be decoded, usually obtained from the	 errno
	       global  variable	 just  before this function is called. This is
	       necessary if you	need to	call any code between the system  call
	       to  be explained	and this function, because many	libc functions
	       will alter the value of errno.

       clockid The original clockid, exactly as	 passed	 to  the  timerfd_cre-
	       ate(2) system call.

       flags   The  original flags, exactly as passed to the timerfd_create(2)
	       system call.

       Example:	This function is intended to be	used in	a fashion  similar  to
       the following example:
	      int result = timerfd_create(clockid, flags);
	      if (result < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_timerfd_create(message,	sizeof(mes-
		  sage), err, clockid, flags);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       The  above  code	 example  is  available	 pre-packaged	as   the   ex-
       plain_timerfd_create_or_die(3) function.

SEE ALSO
       timerfd_create(2)
	       timers that notify via file descriptors

       explain_timerfd_create_or_die(3)
	       timers that notify via file descriptors and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2009 Peter	Miller

						     explain_timerfd_create(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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