GLib.MainContext (original) (raw)
Struct
GLibMainContext
Description [src]
struct GMainContext {
/* No available fields */
}
The GMainContext struct is an opaque data type representing a set of sources to be handled in a main loop.
Constructors
Functions
g_main_context_default
Returns the global-default main context. This is the main context used for main loop functions when a main loop is not explicitly specified, and corresponds to the “main” main loop. See alsog_main_context_get_thread_default().
g_main_context_get_thread_default
Gets the thread-default GMainContext for this thread. Asynchronous operations that want to be able to be run in contexts other than the default one should call this method org_main_context_ref_thread_default() to get aGMainContext to add their GSources to. (Note that even in single-threaded programs applications may sometimes want to temporarily push a non-default context, so it is not safe to assume that this will always return NULL if you are running in the default thread.).
since: 2.22
g_main_context_pusher_free
Pop pusher’s main context as the thread default main context. See g_main_context_pusher_new() for details.
since: 2.64
g_main_context_ref_thread_default
Gets the thread-default GMainContext for this thread, as withg_main_context_get_thread_default(), but also adds a reference to it with g_main_context_ref(). In addition, unlikeg_main_context_get_thread_default(), if the thread-default context is the global-default context, this will return thatGMainContext (with a ref added to it) rather than returningNULL.
since: 2.32
Instance methods
g_main_context_acquire
Tries to become the owner of the specified context. If some other thread is the owner of the context, returns FALSE immediately. Ownership is properly recursive: the owner can require ownership again and will release ownership when g_main_context_release()is called as many times as g_main_context_acquire().
g_main_context_add_poll
Adds a file descriptor to the set of file descriptors polled for this context. This will very seldom be used directly. Instead a typical event source will use g_source_add_unix_fd instead.
g_main_context_check
Passes the results of polling back to the main loop. You should be careful to pass fds and its length n_fds as received fromg_main_context_query(), as this functions relies on assumptions on how fds is filled.
g_main_context_invoke
Invokes a function in such a way that context is owned during the invocation of function.
since: 2.28
g_main_context_is_owner
Determines whether this thread holds the (recursive) ownership of this GMainContext. This is useful to know before waiting on another thread that may be blocking to get ownership of context.
since: 2.10
g_main_context_iteration
Runs a single iteration for the given main loop. This involves checking to see if any event sources are ready to be processed, then if no events sources are ready and may_block is TRUE, waiting for a source to become ready, then dispatching the highest priority events sources that are ready. Otherwise, if may_block is FALSEsources are not waited to become ready, only those highest priority events sources will be dispatched (if any), that are ready at this given moment without further waiting.
g_main_context_prepare
Prepares to poll sources within a main loop. The resulting information for polling is determined by calling g_main_context_query().
g_main_context_push_thread_default
Acquires context 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 context and deliver their results to its main loop, rather than running under the global default main context in the main thread. Note that calling this function changes the context returned by g_main_context_get_thread_default(), not the one returned by g_main_context_default(), so it does not affect the context used by functions like g_idle_add().
since: 2.22
g_main_context_pusher_new
Push main_context as the new thread-default main context for the current thread, using g_main_context_push_thread_default(), and return a new GMainContextPusher. Pop with g_main_context_pusher_free(). Using g_main_context_pop_thread_default() on main_context while aGMainContextPusher exists for it can lead to undefined behaviour.
since: 2.64
g_main_context_query
Determines information necessary to poll this main loop. You should be careful to pass the resulting fds array and its length n_fdsas is when calling g_main_context_check(), as this function relies on assumptions made when the array is filled.
g_main_context_release
Releases ownership of a context previously acquired by this thread with g_main_context_acquire(). If the context was acquired multiple times, the ownership will be released only when g_main_context_release()is called as many times as it was acquired.
g_main_context_set_poll_func
Sets the function to use to handle polling of file descriptors. It will be used instead of the poll() system call (or GLib’s replacement function, which is used wherepoll() isn’t available).
g_main_context_unref
Decreases the reference count on a GMainContext object by one. If the result is zero, free the context and free all associated memory.
g_main_context_wait
Tries to become the owner of the specified context, as with g_main_context_acquire(). But if another thread is the owner, atomically drop mutex and wait on cond until that owner releases ownership or until cond is signaled, then try again (once) to become the owner.
deprecated: 2.58
g_main_context_wakeup
If context is currently blocking in g_main_context_iteration()waiting for a source to become ready, cause it to stop blocking and return. Otherwise, cause the next invocation ofg_main_context_iteration() to return without blocking.