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explain_lstat(3)	    Library Functions Manual		explain_lstat(3)

NAME
     explain_lstat - explain lstat(3) errors

SYNOPSIS
     #include <libexplain/lstat.h>
     const char *explain_lstat(const char *pathname, const struct stat *buf);
     void  explain_message_lstat(char  *message,  int  message_size,  const char
     *pathname, const struct stat *buf);
     const char *explain_errno_lstat(int errnum,  const  char  *pathname,  const
     struct stat *buf);
     void  explain_message_errno_lstat(char  *message, int message_size, int er-
     rnum, const char *pathname, const struct stat *buf);

DESCRIPTION
     These functions may be used to obtains explanations for lstat(2) errors.

   explain_lstat
     const char *explain_lstat(const char *pathname, const struct stat *buf);

     The explain_lstat function is used to obtain an explanation of an error re-
     turned by the lstat(2) function.  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 de-
     coded.

     This function is intended to be used in a fashion similar to the  following
     example:
	    if (lstat(pathname, &buf) < 0)
	    {
		fprintf(stderr, '%s0, explain_lstat(pathname, &buf));
		exit(EXIT_FAILURE);
	    }

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

     buf     The original buf, exactly as passed to the lstat(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  ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain function which shares this buffer, including other threads.

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

   explain_errno_lstat
     "const char *explain_errno_lstat(int errnum, const  char  *pathname,  const
     struct stat *buf);

     The explain_errno_lstat function is used to obtain an explanation of an er-
     ror  returned by the lstat(2) function.  The least the message will contain
     is the value of strerror(errnum), but usually it will do much  better,  and
     indicate the underlying cause in more detail.

     This  function is intended to be used in a fashion similar to the following
     example:
	    if (lstat(pathname, &buf) < 0)
	    {
		int err = errno;
		fprintf(stderr, '%s0, explain_errno_lstat(err, pathname, &buf));
		exit(EXIT_FAILURE);
	    }

     errnum  The error value to be decoded,  usually  obtained	from  the  errno
	     global  variable just before this function is called.  This is nec-
	     essary 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.

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

     buf     The original buf, exactly as passed to the lstat(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  ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain function which shares this buffer, including other threads.

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

   explain_message_lstat
     void explain_message_lstat(char  *message,  int  message_size,  const  char
     *pathname, const struct stat *buf);

     The  explain_message_lstat  function is used to obtain an explanation of an
     error returned by the lstat(2) function. 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 de-
     coded.

     This function is intended to be used in a fashion similar to the  following
     example:
	    if (lstat(pathname, &buf) < 0)
	    {
		char message[3000];
		explain_message_lstat(message, sizeof(message), pathname, &buf);
		fprintf(stderr, '%s0, message);
		exit(EXIT_FAILURE);
	    }

     message
	     The  location  in	which  to store the returned message.  Because a
	     message return buffer has been supplied, this  function  is  thread
	     safe.

     message_size
	     The  size	in  bytes of the location in which to store the returned
	     message.

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

     buf     The original buf, exactly as passed to the lstat(2) system call.

   explain_message_errno_lstat
     void  explain_message_errno_lstat(char  *message, int message_size, int er-
     rnum, const char *pathname, const struct stat *buf);

     The explain_message_errno_lstat function is used to obtain  an  explanation
     of  an error returned by the lstat(2) function.  The least the message will
     contain is the value of strerror(errnum), but usually it will do much  bet-
     ter, and indicate the underlying cause in more detail.

     This  function is intended to be used in a fashion similar to the following
     example:
	    if (lstat(pathname, &buf) < 0)
	    {
		int err = errno;
		char message[3000];
		explain_message_errno_lstat(message, sizeof(message), err,
		    pathname, &buf);
		fprintf(stderr, '%s0, message);
		exit(EXIT_FAILURE);
	    }

     message
	     The location in which to store the  returned  message.   Because  a
	     message  return  buffer  has been supplied, this function is thread
	     safe.

     message_size
	     The size in bytes of the location in which to  store  the	returned
	     message.

     errnum  The  error  value	to  be	decoded, usually obtained from the errno
	     global variable just before this function is called.  This is  nec-
	     essary  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.

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

     buf     The original buf, exactly as passed to the lstat(2) system call.

COPYRIGHT
     libexplain version 1.3
     Copyright (C) 2008 Peter Miller

AUTHOR
     Written by Peter Miller <pmiller@opensource.org.au>

								explain_lstat(3)

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