man3/pthread_mutex_consistent.3

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  26 .TH PTHREAD_MUTEX_CONSISTENT 3 2019-10-10 "Linux" "Linux Programmer's Manual"
  27 .SH NAME
  28 pthread_mutex_consistent \- make a robust mutex consistent
  29 .SH SYNOPSIS
  30 .nf
  31 .B #include <pthread.h>
  32 .PP
  33 .BI "int pthread_mutex_consistent(pthread_mutex_t *" mutex ");"
  34 .fi
  35 .PP
  36 Compile and link with \fI\-pthread\fP.
  37 .PP
  38 .in -4n
  39 Feature Test Macro Requirements for glibc (see
  40 .BR feature_test_macros (7)):
  41 .in
  42 .PP
  43 .BR pthread_mutex_consistent ():
  44 .br
  45 .RS 4
  46 .ad l
  47 _POSIX_C_SOURCE >= 200809L
  48 .RE
  49 .ad
  50 .SH DESCRIPTION
  51 This function makes a robust mutex consistent if it is in an inconsistent
  52 state.
  53 A mutex can be left in an inconsistent state if its owner terminates
  54 while holding the mutex, in which case the next owner who acquires the
  55 mutex will succeed and be notified by a return value of
  56 .BR EOWNERDEAD
  57 from a call to
  58 .BR pthread_mutex_lock ().
  59 .SH RETURN VALUE
  60 On success,
  61 .IR pthread_mutex_consistent ()
  62 returns 0.
  63 Otherwise,
  64 it returns a positive error number to indicate the cause of the error.
  65 .SH ERRORS
  66 .TP
  67 .B EINVAL
  68 The mutex is either not robust or is not in an inconsistent state.
  69 .SH VERSIONS
  70 .BR pthread_mutex_consistent ()
  71 was added to glibc in version 2.12.
  72 .SH CONFORMING TO
  73 POSIX.1-2008.
  74 .SH NOTES
  75 .BR pthread_mutex_consistent ()
  76 simply informs the implementation that the state (shared data)
  77 guarded by the mutex has been restored to a consistent state and that
  78 normal operations can now be performed with the mutex.
  79 It is the application's responsibility to ensure that the
  80 shared data has been restored to a consistent state before calling
  81 .BR pthread_mutex_consistent ().
  82 .PP
  83 Before the addition of
  84 .BR pthread_mutex_consistent ()
  85 to POSIX,
  86 glibc defined the following equivalent nonstandard function if
  87 .BR _GNU_SOURCE
  88 was defined:
  89 .PP
  90 .nf
  91 .BI "int pthread_mutex_consistent(const pthread_mutex_t *" mutex );
  92 .fi
  93 .PP
  94 This GNU-specific API, which first appeared in glibc 2.4,
  95 is nowadays obsolete and should not be used in new programs.
  96 .SH EXAMPLE
  97 See
  98 .BR pthread_mutexattr_setrobust (3).
  99 .SH SEE ALSO
 100 .ad l
 101 .nh
 102 .BR pthread_mutex_lock (3),
 103 .BR pthread_mutexattr_init (3),
 104 .BR pthread_mutexattr_getrobust (3),
 105 .BR pthread_mutexattr_setrobust (3),
 106 .BR pthreads (7)