NAME

       explain_futimes - explain futimes(3) errors

SYNOPSIS

       #include <libexplain/futimes.h>
       const char *explain_futimes(int fildes, const struct timeval *tv);
       const char *explain_errno_futimes(int errnum, int fildes, const struct timeval *tv);
       void  explain_message_futimes(char  *message,  int  message_size, int fildes, const struct
       timeval *tv);
       void  explain_message_errno_futimes(char  *message,  int  message_size,  int  errnum,  int
       fildes, const struct timeval *tv);

DESCRIPTION

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

   explain_futimes
       const char *explain_futimes(int fildes, const struct timeval *tv);

       The explain_futimes function is used to obtain an explanation of an error returned by  the
       futimes(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.

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

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

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

       tv      The original tv, exactly as passed to the futimes(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.

   explain_errno_futimes
       const char *explain_errno_futimes(int errnum, int fildes, const struct timeval *tv);

       The explain_errno_futimes function is used to obtain an explanation of an  error  returned
       by  the  futimes(3)  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 (futimes(fildes, tv) < 0)
              {
                  int err = errno;
                  fprintf(stderr, "%s\n", explain_errno_futimes(err, fildes, tv));
                  exit(EXIT_FAILURE);
              }

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

       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 futimes(3) system call.

       tv      The original tv, exactly as passed to the futimes(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.

   explain_message_futimes
       void  explain_message_futimes(char  *message,  int  message_size, int fildes, const struct
       timeval *tv);

       The explain_message_futimes function may be used to  obtain an  explanation  of  an  error
       returned  by  the futimes(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.

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

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

       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 futimes(3) system call.

       tv      The original tv, exactly as passed to the futimes(3) system call.

   explain_message_errno_futimes
       void  explain_message_errno_futimes(char  *message,  int  message_size,  int  errnum,  int
       fildes, const struct timeval *tv);

       The explain_message_errno_futimes function may be used to  obtain  an  explanation  of  an
       error  returned  by the futimes(3) 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 (futimes(fildes, tv) < 0)
              {
                  int err = errno;
                  char message[3000];
                  explain_message_errno_futimes(message, sizeof(message), err, fildes, tv);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

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

       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 futimes(3) system call.

       tv      The original tv, exactly as passed to the futimes(3) system call.

SEE ALSO

       futimes(3)
               change file timestamps

       explain_futimes_or_die(3)
               change file timestamps and report errors

COPYRIGHT

       libexplain version 1.4
       Copyright (C) 2008 Peter Miller

                                                                               explain_futimes(3)