push_thread_default


Description:

[ Version ( since = "2.22" ) ]
public void push_thread_default ()

Acquires this and sets it as the thread-default context for the current thread.

This will cause certain asynchronous operations (such as most gio-based I/O) which are started in this thread to run under this and deliver their results to its main loop, rather than running under the global default context in the main thread. Note that calling this function changes the context returned by get_thread_default, not the one returned by @default, so it does not affect the context used by functions like g_idle_add.

Normally you would call this function shortly after creating a new thread, passing it a MainContext which will be run by a MainLoop in that thread, to set a new default context for all async operations in that thread. In this case you may not need to ever call pop_thread_default, assuming you want the new MainContext to be the default for the whole lifecycle of the thread.

If you don't have control over how the new thread was created (e.g. in the new thread isn't newly created, or if the thread life cycle is managed by a ThreadPool), it is always suggested to wrap the logic that needs to use the new MainContext inside a push_thread_default / pop_thread_default pair, otherwise threads that are re-used will end up never explicitly releasing the MainContext reference they hold.

In some cases you may want to schedule a single operation in a non-default context, or temporarily use a non-default context in the main thread. In that case, you can wrap the call to the asynchronous operation inside a push_thread_default / pop_thread_default pair, but it is up to you to ensure that no other asynchronous operations accidentally get started while the non-default context is active.

Beware that libraries that predate this function may not correctly handle being used from a thread with a thread-default context. Eg, see g_file_supports_thread_contexts.

Parameters:

this

a MainContext, or null for the global default context