Copyright | Will Thompson Iñaki García Etxebarria and Jonas Platte |
---|---|
License | LGPL-2.1 |
Maintainer | Iñaki García Etxebarria (inaki@blueleaf.cc) |
Safe Haskell | None |
Language | Haskell2010 |
The Thread
struct represents a running thread. This struct
is returned by g_thread_new()
or g_thread_try_new()
. You can
obtain the Thread
struct representing the current thread by
calling threadSelf
.
GThread is refcounted, see threadRef
and threadUnref
.
The thread represented by it holds a reference while it is running,
and threadJoin
consumes the reference that it is given, so
it is normally not necessary to manage GThread references
explicitly.
The structure is opaque -- none of its fields may be directly accessed.
Synopsis
- newtype Thread = Thread (ManagedPtr Thread)
- noThread :: Maybe Thread
- threadErrorQuark :: (HasCallStack, MonadIO m) => m Word32
- threadExit :: (HasCallStack, MonadIO m) => Ptr () -> m ()
- threadJoin :: (HasCallStack, MonadIO m) => Thread -> m (Ptr ())
- threadRef :: (HasCallStack, MonadIO m) => Thread -> m Thread
- threadSelf :: (HasCallStack, MonadIO m) => m Thread
- threadUnref :: (HasCallStack, MonadIO m) => Thread -> m ()
- threadYield :: (HasCallStack, MonadIO m) => m ()
Exported types
Memory-managed wrapper type.
Instances
BoxedObject Thread Source # | |
Methods
errorQuark
threadErrorQuark :: (HasCallStack, MonadIO m) => m Word32 Source #
No description available in the introspection data.
exit
:: (HasCallStack, MonadIO m) | |
=> Ptr () |
|
-> m () |
Terminates the current thread.
If another thread is waiting for us using threadJoin
then the
waiting thread will be woken up and get retval
as the return value
of threadJoin
.
Calling threadExit
with a parameter retval
is equivalent to
returning retval
from the function func
, as given to g_thread_new()
.
You must only call threadExit
from a thread that you created
yourself with g_thread_new()
or related APIs. You must not call
this function from a thread created with another threading library
or or from within a ThreadPool
.
join
:: (HasCallStack, MonadIO m) | |
=> Thread |
|
-> m (Ptr ()) | Returns: the return value of the thread |
Waits until thread
finishes, i.e. the function func
, as
given to g_thread_new()
, returns or threadExit
is called.
If thread
has already terminated, then threadJoin
returns immediately.
Any thread can wait for any other thread by calling threadJoin
,
not just its 'creator'. Calling threadJoin
from multiple threads
for the same thread
leads to undefined behaviour.
The value returned by func
or given to threadExit
is
returned by this function.
threadJoin
consumes the reference to the passed-in thread
.
This will usually cause the Thread
struct and associated resources
to be freed. Use threadRef
to obtain an extra reference if you
want to keep the GThread alive beyond the threadJoin
call.
ref
:: (HasCallStack, MonadIO m) | |
=> Thread |
|
-> m Thread | Returns: a new reference to |
Increase the reference count on thread
.
Since: 2.32
self
:: (HasCallStack, MonadIO m) | |
=> m Thread | Returns: the |
This function returns the Thread
corresponding to the
current thread. Note that this function does not increase
the reference count of the returned struct.
This function will return a Thread
even for threads that
were not created by GLib (i.e. those created by other threading
APIs). This may be useful for thread identification purposes
(i.e. comparisons) but you must not use GLib functions (such
as threadJoin
) on these threads.
unref
:: (HasCallStack, MonadIO m) | |
=> Thread |
|
-> m () |
Decrease the reference count on thread
, possibly freeing all
resources associated with it.
Note that each thread holds a reference to its Thread
while
it is running, so it is safe to drop your own reference to it
if you don't need it anymore.
Since: 2.32
yield
threadYield :: (HasCallStack, MonadIO m) => m () Source #
Causes the calling thread to voluntarily relinquish the CPU, so that other threads can run.
This function is often used as a method to make busy wait less evil.