PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       pthread_condattr_destroy,   pthread_condattr_init   —  destroy  and  initialize  the  condition  variable
       attributes object

SYNOPSIS

       #include <pthread.h>

       int pthread_condattr_destroy(pthread_condattr_t *attr);
       int pthread_condattr_init(pthread_condattr_t *attr);

DESCRIPTION

       The pthread_condattr_destroy() function shall destroy a condition variable attributes object; the  object
       becomes,  in  effect,  uninitialized.  An  implementation may cause pthread_condattr_destroy() to set the
       object referenced by attr to an invalid value. A destroyed attr attributes object  can  be  reinitialized
       using  pthread_condattr_init();  the  results  of  otherwise  referencing  the  object  after it has been
       destroyed are undefined.

       The pthread_condattr_init() function shall initialize a condition variable attributes  object  attr  with
       the default value for all of the attributes defined by the implementation.

       Results  are  undefined  if  pthread_condattr_init()  is  called  specifying  an already initialized attr
       attributes object.

       After a condition variable attributes object has been used to initialize one or more condition variables,
       any function affecting the attributes object (including destruction)  shall  not  affect  any  previously
       initialized condition variables.

       This  volume  of  POSIX.1‐2017  requires  two  attributes,  the  clock  attribute  and the process-shared
       attribute.

       Additional attributes, their default values, and the names of the associated functions  to  get  and  set
       those attribute values are implementation-defined.

       The  behavior is undefined if the value specified by the attr argument to pthread_condattr_destroy() does
       not refer to an initialized condition variable attributes object.

RETURN VALUE

       If successful, the pthread_condattr_destroy() and pthread_condattr_init() functions  shall  return  zero;
       otherwise, an error number shall be returned to indicate the error.

ERRORS

       The pthread_condattr_init() function shall fail if:

       ENOMEM Insufficient memory exists to initialize the condition variable attributes object.

       These functions shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       A  process-shared  attribute  has  been  defined  for condition variables for the same reason it has been
       defined for mutexes.

       If an implementation detects that the value specified by the attr argument to  pthread_condattr_destroy()
       does  not  refer  to  an  initialized  condition  variable  attributes object, it is recommended that the
       function should fail and report an [EINVAL] error.

       See also pthread_attr_destroy() and pthread_mutex_destroy().

FUTURE DIRECTIONS

       None.

SEE ALSO

       pthread_attr_destroy(), pthread_cond_destroy(), pthread_condattr_getpshared(), pthread_create(),
       pthread_mutex_destroy()

       The Base Definitions volume of POSIX.1‐2017, <pthread.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group  Base
       Specifications  Issue  7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
       Engineers, Inc and The Open Group.  In the event of any discrepancy between this version and the original
       IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee  document.
       The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                      PTHREAD_CONDATTR_DESTROY(3POSIX)