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NAME

       explain_tcgetattr - explain tcgetattr(3) errors

SYNOPSIS

       #include <libexplain/tcgetattr.h>
       const char *explain_tcgetattr(int fildes, struct termios *data);
       const char *explain_errno_tcgetattr(int errnum, int fildes, struct
       termios *data);
       void explain_message_tcgetattr(char *message, int message_size, int
       fildes, struct termios *data);
       void explain_message_errno_tcgetattr(char *message, int message_size,
       int errnum, int fildes, struct termios *data);

DESCRIPTION

       These functions may be used to obtain explanations for errors  returned
       by the tcgetattr(3) system call.

   explain_tcgetattr
       const char *explain_tcgetattr(int fildes, struct termios *data);

       The  explain_tcgetattr  function is used to obtain an explanation of an
       error returned by the tcgetattr(3) 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.

       fildes  The  original  fildes,  exactly  as  passed to the tcgetattr(3)
               system call.

       data    The original data, exactly as passed to the tcgetattr(3) 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.

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

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

   explain_errno_tcgetattr
       const char *explain_errno_tcgetattr(int errnum, int fildes, struct
       termios *data);

       The  explain_errno_tcgetattr  function is used to obtain an explanation
       of an error returned by the tcgetattr(3) 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.

       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.

       fildes  The  original  fildes,  exactly  as  passed to the tcgetattr(3)
               system call.

       data    The original data, exactly as passed to the tcgetattr(3) 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.

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

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

   explain_message_tcgetattr
       void explain_message_tcgetattr(char *message, int message_size, int
       fildes, struct termios *data);

       The explain_message_tcgetattr function is used to obtain an explanation
       of  an  error  returned by the tcgetattr(3) 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
               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.

       fildes  The original fildes, exactly  as  passed  to  the  tcgetattr(3)
               system call.

       data    The original data, exactly as passed to the tcgetattr(3) system
               call.

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

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

   explain_message_errno_tcgetattr
       void explain_message_errno_tcgetattr(char *message, int message_size,
       int errnum, int fildes, struct termios *data);

       The explain_message_errno_tcgetattr  function  is  used  to  obtain  an
       explanation  of an error returned by the tcgetattr(3) 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
               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.

       fildes  The  original  fildes,  exactly  as  passed to the tcgetattr(3)
               system call.

       data    The original data, exactly as passed to the tcgetattr(3) system
               call.

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

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

SEE ALSO

       tcgetattr(3)
               get terminal parameters

       explain_tcgetattr_or_die(3)
               get terminal parameters and report errors

COPYRIGHT

       libexplain version 0.19
       Copyright (C) 2009 Peter Miller

                                                          explain_tcgetattr(3)