Provided by: libexplain-dev_1.4.D001-8_amd64 bug

NAME

       explain_setvbuf - explain setvbuf(3) errors

SYNOPSIS

       #include <libexplain/setvbuf.h>
       const char *explain_setvbuf(FILE *fp, char *data, int mode, size_t size);
       const char *explain_errno_setvbuf(int errnum, FILE *fp, char *data, int mode, size_t
       size);
       void explain_message_setvbuf(char *message, int message_size, FILE *fp, char *data, int
       mode, size_t size);
       void explain_message_errno_setvbuf(char *message, int message_size, int errnum, FILE *fp,
       char *data, int mode, size_t size);

DESCRIPTION

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

   explain_setvbuf
       const char *explain_setvbuf(FILE *fp, char *data, int mode, size_t size);

       The  explain_setvbuf function is used to obtain an explanation of an error returned by the
       setvbuf(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.

       fp      The original fp, exactly as passed to the setvbuf(3) system call.

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

       mode    The original mode, exactly as passed to the setvbuf(3) system call.

       size    The original size, exactly as passed to the setvbuf(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 (setvbuf(fp, data, mode, size) < 0)
              {
                  fprintf(stderr, "%s\n", explain_setvbuf(fp, data, mode, size));
                  exit(EXIT_FAILURE);
              }

       The  above  code  example  is  available  pre‐packaged  as  the  explain_setvbuf_or_die(3)
       function.

   explain_errno_setvbuf
       const char *explain_errno_setvbuf(int errnum, FILE *fp, char *data, int mode, size_t
       size);

       The  explain_errno_setvbuf  function is used to obtain an explanation of an error returned
       by the setvbuf(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.

       fp      The original fp, exactly as passed to the setvbuf(3) system call.

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

       mode    The original mode, exactly as passed to the setvbuf(3) system call.

       size    The original size, exactly as passed to the setvbuf(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 (setvbuf(fp, data, mode, size) < 0)
              {
                  int err = errno;
                  fprintf(stderr, "%s\n", explain_errno_setvbuf(err, fp, data, mode, size));
                  exit(EXIT_FAILURE);
              }

       The  above  code  example  is  available  pre‐packaged  as  the  explain_setvbuf_or_die(3)
       function.

   explain_message_setvbuf
       void explain_message_setvbuf(char *message, int message_size, FILE *fp, char *data, int
       mode, size_t size);

       The explain_message_setvbuf function is used to obtain an explanation of an error returned
       by  the  setvbuf(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.

       fp      The original fp, exactly as passed to the setvbuf(3) system call.

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

       mode    The original mode, exactly as passed to the setvbuf(3) system call.

       size    The original size, exactly as passed to the setvbuf(3) system call.

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

       The  above  code  example  is  available  pre‐packaged  as  the  explain_setvbuf_or_die(3)
       function.

   explain_message_errno_setvbuf
       void explain_message_errno_setvbuf(char *message, int message_size, int errnum, FILE *fp,
       char *data, int mode, size_t size);

       The  explain_message_errno_setvbuf  function  is used to obtain an explanation of an error
       returned by the setvbuf(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.

       fp      The original fp, exactly as passed to the setvbuf(3) system call.

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

       mode    The original mode, exactly as passed to the setvbuf(3) system call.

       size    The original size, exactly as passed to the setvbuf(3) system call.

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

       The  above  code  example  is  available  pre‐packaged  as  the  explain_setvbuf_or_die(3)
       function.

SEE ALSO

       setvbuf(3)
               stream buffering operations

       explain_setvbuf_or_die(3)
               stream buffering operations and report errors

COPYRIGHT

       libexplain version 1.4
       Copyright (C) 2010 Peter Miller

                                                                               explain_setvbuf(3)