Provided by: libexplain-dev_1.4.D001-7_amd64 bug

NAME

       explain_ftruncate - explain ftruncate(2) errors

SYNOPSIS

       #include <libexplain/ftruncate.h>
       const char *explain_ftruncate(int fildes, long long length);
       const char *explain_errno_ftruncate(int errnum, int fildes, long long length);
       void  explain_message_ftruncate(char  *message,  int  message_size,  int fildes, long long
       length);
       void explain_message_errno_ftruncate(char *message,  int  message_size,  int  errnum,  int
       fildes, long long length);

DESCRIPTION

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

   explain_ftruncate
       const char *explain_ftruncate(int fildes, long long length);

       The explain_ftruncate function is used to obtain an explanation of an  error  returned  by
       the  ftruncate(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 (ftruncate(fildes, length) < 0)
              {
                  fprintf(stderr, "%s\n", explain_ftruncate(fildes, length));
                  exit(EXIT_FAILURE);
              }

       fildes  The original fildes, exactly as passed to the ftruncate(2) system call.

       length  The original length, exactly as passed to the ftruncate(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_ftruncate
       const char *explain_errno_ftruncate(int errnum, int fildes, long long length);

       The explain_errno_ftruncate function is used to obtain an explanation of an error returned
       by the ftruncate(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 (ftruncate(fildes, length) < 0)
              {
                  int err = errno;
                  fprintf(stderr, "%s\n", explain_errno_ftruncate(err, fildes, length));
                  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.

       fildes  The original fildes, exactly as passed to the ftruncate(2) system call.

       length  The original length, exactly as passed to the ftruncate(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_ftruncate
       void  explain_message_ftruncate(char  *message,  int  message_size,  int fildes, long long
       length);

       The explain_message_ftruncate function may be used to  obtain an explanation of  an  error
       returned by the ftruncate(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 (ftruncate(fildes, length) < 0)
              {
                  char message[3000];
                  explain_message_ftruncate(message, sizeof(message), fildes, length);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       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 ftruncate(2) system call.

       length  The original length, exactly as passed to the ftruncate(2) system call.

   explain_message_errno_ftruncate
       void explain_message_errno_ftruncate(char *message,  int  message_size,  int  errnum,  int
       fildes, long long length);

       The  explain_message_errno_ftruncate  function  may be used to obtain an explanation of an
       error returned by the ftruncate(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 (ftruncate(fildes, length) < 0)
              {
                  int err = errno;
                  char message[3000];
                  explain_message_errno_ftruncate(message, sizeof(message), err,
                      fildes, length);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       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 ftruncate(2) system call.

       length  The original length, exactly as passed to the ftruncate(2) system call.

SEE ALSO

       ftruncate(2)
               truncate a file to a specified length

       explain_ftruncate_or_die(3)
               truncate a file and report errors

COPYRIGHT

       libexplain version 1.4
       Copyright (C) 2008 Peter Miller

                                                                             explain_ftruncate(3)