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explain_uname(3)	    Library Functions Manual		explain_uname(3)

NAME
     explain_uname - explain uname(2) errors

SYNOPSIS
     #include <libexplain/uname.h>
     const char *explain_uname(struct utsname *data);
     const char *explain_errno_uname(int errnum, struct utsname *data);
     void explain_message_uname(char *message, int message_size, struct utsname
     *data);
     void explain_message_errno_uname(char *message, int message_size, int er-
     rnum, struct utsname *data);

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

   explain_uname
     const char *explain_uname(struct utsname *data);

     The explain_uname function is used to obtain an explanation of an error re-
     turned by the uname(2) system call. The least the message will  contain  is
     the value of strerror(errno), but usually it will do much better, and indi-
     cate the underlying cause in more detail.

     The  errno global variable will be used to obtain the error value to be de-
     coded.

     data    The original data, exactly as passed to the uname(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.

     Example:  This  function is intended to be used in a fashion similar to the
     following example:
	    if (uname(data) < 0)
	    {
		fprintf(stderr, "%s\n", explain_uname(data));
		exit(EXIT_FAILURE);
	    }

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

   explain_errno_uname
     const char *explain_errno_uname(int errnum, struct utsname *data);

     The explain_errno_uname function is used to obtain an explanation of an er-
     ror  returned  by the uname(2) system call. The least the message will con-
     tain 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 neces-
	     sary if you need to call any code between the system call to be ex-
	     plained and this function, because many libc functions  will  alter
	     the value of errno.

     data    The original data, exactly as passed to the uname(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.

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

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

   explain_message_uname
     void explain_message_uname(char *message, int message_size, struct utsname
     *data);

     The explain_message_uname function is used to obtain an explanation  of  an
     error returned by the uname(2) system call. The least the message will con-
     tain  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.

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

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

     data    The original data, exactly as passed to the uname(2) system call.

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

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

   explain_message_errno_uname
     void explain_message_errno_uname(char *message, int message_size, int er-
     rnum, struct utsname *data);

     The  explain_message_errno_uname  function is used to obtain an explanation
     of an error returned by the uname(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	suitable
	     message return buffer is 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 ex-
	     plained  and  this function, because many libc functions will alter
	     the value of errno.

     data    The original data, exactly as passed to the uname(2) system call.

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

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

SEE ALSO
     uname(2)
	     get name and information about current kernel

     explain_uname_or_die(3)
	     get name and information about current kernel and report errors

COPYRIGHT
     libexplain version 1.3
     Copyright (C) 2013 Peter Miller

								explain_uname(3)

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