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explain_fchownat(3)	   Library Functions Manual	   explain_fchownat(3)

NAME
       explain_fchownat	- explain fchownat(2) errors

SYNOPSIS
       #include	<libexplain/fchownat.h>
       const char *explain_fchownat(int	dirfd, const char *pathname, int
       owner, int group, int flags);
       const char *explain_errno_fchownat(int errnum, int dirfd, const char
       *pathname, int owner, int group,	int flags);
       void explain_message_fchownat(char *message, int	message_size, int
       dirfd, const char *pathname, int	owner, int group, int flags);
       void explain_message_errno_fchownat(char	*message, int message_size,
       int errnum, int dirfd, const char *pathname, int	owner, int group, int
       flags);

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

   explain_fchownat
       const char *explain_fchownat(int	dirfd, const char *pathname, int
       owner, int group, int flags);

       The explain_fchownat function is	used to	obtain an  explanation	of  an
       error  returned	by  the	fchownat(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.

       dirfd   The original dirfd, exactly as passed to	the fchownat(2)	system
	       call.

       pathname
	       The  original  pathname,	 exactly  as passed to the fchownat(2)
	       system call.

       owner   The original owner, exactly as passed to	the fchownat(2)	system
	       call.

       group   The original group, exactly as passed to	the fchownat(2)	system
	       call.

       flags   The original flags, exactly as passed to	the fchownat(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:
	      if (fchownat(dirfd, pathname, owner, group, flags) < 0)
	      {
		  fprintf(stderr, "%s\n", explain_fchownat(dirfd, pathname,
		  owner, group,	flags));
		  exit(EXIT_FAILURE);
	      }

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

   explain_errno_fchownat
       const char *explain_errno_fchownat(int errnum, int dirfd, const char
       *pathname, int owner, int group,	int flags);

       The explain_errno_fchownat function is used to obtain an	explanation of
       an  error  returned by the fchownat(2) system call.  The	least the mes-
       sage 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.

       dirfd   The original dirfd, exactly as passed to	the fchownat(2)	system
	       call.

       pathname
	       The original pathname, exactly as  passed  to  the  fchownat(2)
	       system call.

       owner   The original owner, exactly as passed to	the fchownat(2)	system
	       call.

       group   The original group, exactly as passed to	the fchownat(2)	system
	       call.

       flags   The original flags, exactly as passed to	the fchownat(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:
	      if (fchownat(dirfd, pathname, owner, group, flags) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_fchownat(err, dirfd,
		  pathname, owner, group, flags));
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_fchownat
       void explain_message_fchownat(char *message, int	message_size, int
       dirfd, const char *pathname, int	owner, int group, int flags);

       The  explain_message_fchownat function is used to obtain	an explanation
       of an error returned by the fchownat(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.

       dirfd   The original dirfd, exactly as passed to	the fchownat(2)	system
	       call.

       pathname
	       The  original  pathname,	 exactly  as passed to the fchownat(2)
	       system call.

       owner   The original owner, exactly as passed to	the fchownat(2)	system
	       call.

       group   The original group, exactly as passed to	the fchownat(2)	system
	       call.

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

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      if (fchownat(dirfd, pathname, owner, group, flags) < 0)
	      {
		  char message[3000];
		  explain_message_fchownat(message, sizeof(message), dirfd,
		  pathname, owner, group, flags);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_errno_fchownat
       void explain_message_errno_fchownat(char	*message, int message_size,
       int errnum, int dirfd, const char *pathname, int	owner, int group, int
       flags);

       The explain_message_errno_fchownat function is used to obtain an	expla-
       nation  of an error returned by the fchownat(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 de-
       tail.

       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.

       dirfd   The original dirfd, exactly as passed to	the fchownat(2)	system
	       call.

       pathname
	       The original pathname, exactly as  passed  to  the  fchownat(2)
	       system call.

       owner   The original owner, exactly as passed to	the fchownat(2)	system
	       call.

       group   The original group, exactly as passed to	the fchownat(2)	system
	       call.

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

       Example:	This function is intended to be	used in	a fashion  similar  to
       the following example:
	      if (fchownat(dirfd, pathname, owner, group, flags) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_fchownat(message, sizeof(message),
		  err, dirfd, pathname,	owner, group, flags);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

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

SEE ALSO
       fchownat(2)
	       change ownership	of a file relative to a	directory

       explain_fchownat_or_die(3)
	       change  ownership  of a file relative to	a directory and	report
	       errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2013 Peter	Miller

							   explain_fchownat(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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