Condition attribute objects are used to specify parameters to
pthread_cond_init().
The
pthread_condattr_init()
function initializes a condition attribute object with the default attributes.
The
pthread_condattr_destroy()
function destroys a condition attribute object.
The
pthread_condattr_getclock()
function will put the value of the clock attribute from
attr
into the memory area pointed to by
clock_id.
The
pthread_condattr_setclock()
function will set the clock attribute of
attr
to the value specified in
clock_id.
The clock attribute affects the interpretation of
abstime
in
pthread_cond_timedwait(3)
and may be set to
CLOCK_REALTIME
(default)
or
CLOCK_MONOTONIC.
The
pthread_condattr_getpshared()
function will put the value of the process-shared attribute from
attr
into the memory area pointed to by
pshared.
The
pthread_condattr_setpshared()
function will set the process-shared attribute of
attr
to the value specified in
pshared.
The argument
pshared
may have one of the following values:
PTHREAD_PROCESS_PRIVATE
|
|
The condition variable it is attached to may only be accessed by
threads in the same process as the one that created the object.
|
PTHREAD_PROCESS_SHARED
|
The condition variable it is attached to may be accessed by
threads in processes other than the one that created the object.
|
See
libthr(3)
for details of the implementation of shared condition variables,
and their limitations.