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

NAME

       explain_timerfd_create - explain timerfd_create(2) errors

SYNOPSIS

       #include <libexplain/timerfd_create.h>
       const char *explain_timerfd_create(int clockid, int flags);
       const char *explain_errno_timerfd_create(int errnum, int clockid, int flags);
       void explain_message_timerfd_create(char *message, int message_size, int clockid, int
       flags);
       void explain_message_errno_timerfd_create(char *message, int message_size, int errnum, int
       clockid, int flags);

DESCRIPTION

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

   explain_timerfd_create
       const char *explain_timerfd_create(int clockid, int flags);

       The explain_timerfd_create function is used to obtain an explanation of an error  returned
       by  the  timerfd_create(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.

       clockid The original clockid, exactly as passed to the timerfd_create(2) system call.

       flags   The original flags, exactly as passed to the timerfd_create(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.

       Example:  This  function  is  intended  to  be  used in a fashion similar to the following
       example:
              int result = timerfd_create(clockid, flags);
              if (result < 0)
              {
                  fprintf(stderr, "%s\n", explain_timerfd_create(clockid, flags));
                  exit(EXIT_FAILURE);
              }

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

   explain_errno_timerfd_create
       const char *explain_errno_timerfd_create(int errnum, int clockid, int flags);

       The  explain_errno_timerfd_create  function  is  used to obtain an explanation of an error
       returned by the timerfd_create(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.

       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.

       clockid The original clockid, exactly as passed to the timerfd_create(2) system call.

       flags   The original flags, exactly as passed to the timerfd_create(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.

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

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

   explain_message_timerfd_create
       void explain_message_timerfd_create(char *message, int message_size, int clockid, int
       flags);

       The explain_message_timerfd_create function is used to obtain an explanation of  an  error
       returned  by  the timerfd_create(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.

       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.

       clockid The original clockid, exactly as passed to the timerfd_create(2) system call.

       flags   The original flags, exactly as passed to the timerfd_create(2) system call.

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

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

   explain_message_errno_timerfd_create
       void explain_message_errno_timerfd_create(char *message, int message_size, int errnum, int
       clockid, int flags);

       The  explain_message_errno_timerfd_create  function is used to obtain an explanation of an
       error returned by the timerfd_create(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 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.

       clockid The original clockid, exactly as passed to the timerfd_create(2) system call.

       flags   The original flags, exactly as passed to the timerfd_create(2) system call.

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

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

SEE ALSO

       timerfd_create(2)
               timers that notify via file descriptors

       explain_timerfd_create_or_die(3)
               timers that notify via file descriptors and report errors

COPYRIGHT

       libexplain version 1.4
       Copyright (C) 2009 Peter Miller

                                                                        explain_timerfd_create(3)