Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
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
       errnum, const char *pathname, const struct stat *buf);

DESCRIPTION
       These  functions	 may  be used to obtains explanations for lstat(2) er-
       rors.

   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
       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
       decoded.

       This  function  is intended to be used in a fashion similar to the fol-
       lowing 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	argument list.	This will be overwritten by  the  next
	       call  to	 any libexplain	function which shares this buffer, in-
	       cluding 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.

   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
       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
       better, and indicate the	underlying cause in more detail.

       This  function  is intended to be used in a fashion similar to the fol-
       lowing 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
	       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.

       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	argument list.	This will be overwritten by  the  next
	       call  to	 any libexplain	function which shares this buffer, in-
	       cluding 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.

   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
       decoded.

       This function is	intended to be used in a fashion similar to  the  fol-
       lowing 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 re-
	       turned 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
       errnum, const char *pathname, const struct stat *buf);

       The  explain_message_errno_lstat	function is used to obtain an explana-
       tion of an error	returned by the	lstat(2) function.  The	least the mes-
       sage 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  fol-
       lowing 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 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.

       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)

NAME | SYNOPSIS | DESCRIPTION | COPYRIGHT | AUTHOR

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=explain_lstat&sektion=3&manpath=FreeBSD+12.2-RELEASE+and+Ports>

home | help