Document clock and pshared condvar attributes.

Note: clock accepts CLOCK_VIRTUAL and CLOCK_PROF too, but this seems broken
as it simply waits for the difference of the current and given value of the
clock as if it were CLOCK_MONOTONIC. So document only CLOCK_REALTIME and
CLOCK_MONOTONIC as allowed.

MFC after:	1 week

1 files changed, 94 insertions, 8 deletions

diff --git a/share/man/man3/pthread_condattr.3 b/share/man/man3/pthread_condattr.3
index bf28987..e232ef6 100644
--- a/share/man/man3/pthread_condattr.3
+++ b/share/man/man3/pthread_condattr.3
@@ -26,12 +26,16 @@
 .\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
 .\" $FreeBSD$
-.Dd April 28, 2000
+.Dd May 9, 2010
 .Dt PTHREAD_CONDATTR 3
 .Os
 .Sh NAME
 .Nm pthread_condattr_init ,
-.Nm pthread_condattr_destroy
+.Nm pthread_condattr_destroy ,
+.Nm pthread_condattr_getclock ,
+.Nm pthread_condattr_setclock ,
+.Nm pthread_condattr_getpshared ,
+.Nm pthread_condattr_setpshared ,
 .Nd condition attribute operations
 .Sh LIBRARY
 .Lb libpthread
@@ -41,14 +45,17 @@
 .Fn pthread_condattr_init "pthread_condattr_t *attr"
 .Ft int
 .Fn pthread_condattr_destroy "pthread_condattr_t *attr"
+.Ft int
+.Fn pthread_condattr_getclock "pthread_condattr_t * restrict attr" "clock_t * restrict clock_id"
+.Ft int
+.Fn pthread_condattr_setclock "pthread_condattr_t *attr" "clock_t clock_id"
+.Ft int
+.Fn pthread_condattr_getpshared "pthread_condattr_t * restrict attr" "int * restrict pshared"
+.Ft int
+.Fn pthread_condattr_setpshared "pthread_condattr_t *attr" "int pshared"
 .Sh DESCRIPTION
 Condition attribute objects are used to specify parameters to
 .Fn pthread_cond_init .
-.Fx Ns 's
-implementation of conditions does not support any non-default
-attributes, so these functions are not very useful, though they are required
-to be present by
-.Tn POSIX .
 .Pp
 The
 .Fn pthread_condattr_init
@@ -57,6 +64,52 @@ function initializes a condition attribute object with the default attributes.
 The
 .Fn pthread_condattr_destroy
 function destroys a condition attribute object.
+.Pp
+The
+.Fn pthread_condattr_getclock
+function will put the value of the clock attribute from
+.Fa attr
+into the memory area pointed to by
+.Fa clock_id .
+The
+.Fn pthread_condattr_setclock
+function will set the clock attribute of
+.Fa attr
+to the value specified in
+.Fa clock_id .
+The clock attribute affects the interpretation of
+.Fa abstime
+in
+.Xr pthread_cond_timedwait 3
+and may be set to
+.Dv CLOCK_REALTIME
+(default)
+or
+.Dv CLOCK_MONOTONIC .
+.Pp
+The
+.Fn pthread_condattr_getpshared
+function will put the value of the process-shared attribute from
+.Fa attr
+into the memory area pointed to by
+.Fa pshared .
+The
+.Fn pthread_condattr_setpshared
+function will set the process-shared attribute of
+.Fa attr
+to the value specified in
+.Fa pshared .
+The argument
+.Fa pshared
+may have one of the following values:
+.Bl -tag -width ".Dv PTHREAD_PROCESS_PRIVATE"
+.It Dv 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.
+.It Dv 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.
+.El
 .Sh RETURN VALUES
 If successful, these functions return 0.
 Otherwise, an error number is returned to indicate the error.
@@ -77,8 +130,29 @@ function will fail if:
 Invalid value for
 .Fa attr .
 .El
+.Pp
+The
+.Fn pthread_condattr_setclock
+function will fail if:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The value specified in
+.Fa clock_id
+is not one of the allowed values.
+.El
+.Pp
+The
+.Fn pthread_condattr_setpshared
+function will fail if:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The value specified in
+.Fa pshared
+is not one of the allowed values.
+.El
 .Sh SEE ALSO
-.Xr pthread_cond_init 3
+.Xr pthread_cond_init 3 ,
+.Xr pthread_cond_timedwait 3
 .Sh STANDARDS
 The
 .Fn pthread_condattr_init
@@ -86,3 +160,15 @@ and
 .Fn pthread_condattr_destroy
 functions conform to
 .St -p1003.1-96
+.Sh BUGS
+The implementation of
+condition variables
+does not fully conform to
+.St -p1003.2
+because the process-shared attribute is ignored;
+if any value other than
+.Dv PTHREAD_PROCESSES_PRIVATE
+is specified in a call to
+.Fn pthread_condattr_setpshared ,
+it will return
+.Er EINVAL .