pthread_condattr_getpshared(3T)pthread_condattr_getpshared(3T)NAMEpthread_condattr_getpshared(), pthread_condattr_setpshared() - get or
set the process-shared attribute
SYNOPSISPARAMETERS
attr Pointer to the condition variable attributes object
whose process-shared attribute is to be set/retrieved.
pshared This parameter either specifies the new value of the
process-shared attribute (set function) or it points
to the memory location where the process-shared
attribute of attr is to be returned (get function).
DESCRIPTION
The attributes object attr must have been previously initialized with
the function before these functions are called.
The functions are used to set and retrieve the process-shared attribute
in a condition variable attributes object. The legal values for the
process-shared attribute are:
This option permits a condition variable to be operated upon by
any thread
that has access to the memory where the condition vari‐
able is allocated. The application is responsible for
allocating the condition variable in memory that multiple
processes can access.
The condition variable can be operated on only by threads cre‐
ated within
the same process as the thread that initialized the con‐
dition variable. If threads of differing processes
attempt to operate on such condition variable, the behav‐
ior is undefined.
The default value of process-shared is
sets the process-shared attribute in attr. The new value of the
process-shared attribute of attr is set to the value specified in the
pshared parameter.
retrieves the value of the process-shared attribute from attr. The
value of the process-shared attribute of attr is returned in the
pshared parameter.
RETURN VALUE
Upon successful completion, and return zero. Otherwise, an error num‐
ber is returned to indicate the error (the variable is not set).
ERRORS
If any of the following occur, the and functions return the correspond‐
ing error number:
is not defined and these functions are not supported.
For each of the following conditions, if the condition is detected, the
function returns the corresponding error number:
attr is not a valid condition variable attributes
object.
The value specified by
pshared is not a legal value.
For each of the following conditions, if the condition is detected, the
function returns the corresponding error number:
The value specified by
attr or pshared is invalid.
WARNINGS
If a condition variable is created with the process-shared attribute
defined as the cooperating processes should have access to the memory
in which the condition variable is allocated.
AUTHOR
and were derived from the IEEE POSIX P1003.1c standard.
SEE ALSOpthread_create(3T), pthread_condattr_init(3T), pthread_cond_init(3T),
pthread_mutex_init(3T).
STANDARDS CONFORMANCE
Pthread Librarypthread_condattr_getpshared(3T)