explain_chmod(3)					     Library Functions Manual						  explain_chmod(3)

NAME

       explain_chmod - explain chmod(2) errors

SYNOPSIS

       #include <libexplain/chmod.h>
       const char *explain_chmod(const char *pathname, int mode);
       const char *explain_errno_chmod(int errnum, const char *pathname, int mode);
       void explain_message_chmod(char *message, int message_size, const char *pathname, int mode);
       void explain_message_errno_chmod(char *message, int message_size, int errnum, const char *pathname, int mode);

DESCRIPTION

       These functions may be used to otain explanations for chmod(2) errors.

   explain_chmod
       const char *explain_chmod(const char *pathname, int mode);

       The  explain_chmod  function is used to obtain an explanation of an error returned by the chmod(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.

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

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

       mode    The original mode, exactly as passed to the chmod(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 buffer across all threads, and many other functions in this library.

   explain_errno_chmod
       const char *explain_errno_chmod(int errnum, const char *pathname, int mode);

       The explain_errno_chmod function is used to obtain an explanation of an error returned by the chmod(2) system call.  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 (chmod(pathname) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, '%s0, explain_errno_chmod(err, pathname));
		  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 neces-
	       sary 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 chmod(2) system call.

       mode    The original mode, exactly as passed to the chmod(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 buffer across all threads, and many other functions in this library.

   explain_message_chmod
       void explain_message_chmod(char *message, int message_size, const char *pathname, int mode);

       The  explain_message_chmod  function is used to obtain an explanation of an error returned by the chmod(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.

       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 following example:
	      if (chmod(pathname, mode) < 0)
	      {
		  char message[3000];
		  explain_message_chmod(message, sizeof(message), pathname, mode);
		  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 chmod(2) system call.

       mode    The original mode, exactly as passed to the chmod(2) system call.

   explain_message_errno_chmod
       void explain_message_errno_chmod(char * message, int message_size, int errnum, const char *pathname, int mode);

       The  explain_message_errno_chmod function is used to obtain an explanation of an error returned by the chmod(2) system call.  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 (chmod(pathname) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_chmod(message, sizeof(message), err,
		      pathname);
		  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 neces-
	       sary 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 chmod(2) system call.

       mode    The original mode, exactly as passed to the chmod(2) system call.

COPYRIGHT

       libexplain version 0.52
       Copyright (C) 2008 Peter Miller

AUTHOR

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

																  explain_chmod(3)