Thanks a lot! This makes things a bit more clear. One final question: Is it possible to detect if the default context currently has an active main loop? I want to add IO watches to the default context in a library. Apps using the library may decide to start a main loop themselves (in the default context) or to let the library do this. Of course they could tell the library somehow if there already is a running main loop in the default context, but it would be nice if the library could detect this itself. jcupitt@xxxxxxxxx wrote: > On 10/2/07, Christian Buennig <masala@xxxxxx> wrote: >> * Do main loops exist per process or per thread? >> If I start a main loop in one thread (A) and add an IO watch in >> another thread (B), does this watch get added to the main loop of the >> thread A or B ? > > Each process can have one or more GMainContext. A context holds a set > of IO watches, timeouts, callbacks, etc. There's a default context, > which is generally the only context. If you use the convenience > functions g_timeout_add() etc., they will automatically add to the > default context. You'll need to roll up your own timeout_add() (or > whatever) if you want to add to a different context. > > Each context can have one or more main loops. These main loops are not > active at the same time, instead they nest in a stack with only the > top one active. GTK uses nested main loops to handle modal dialogs. I > imagine the context and all the main loops for that context have to be > created and run in a single thread, but I don't know. It would > certainly reduce confusion if they were. > > So to answer your question, if you have a main loop running in thread > (A) and add an IO watch from thread (B), the callback on input > arriving will be called by (A). Unless you go to a lot of trouble to > add your watch to the non-default context. > >> * If there is only one main loop (regardless of per thread or per >> process), why the function g_main_loop_new()? > > This is for the nesting feature. > >> * What's the purpose of the parameter 'is_running' in >> g_main_loop_new() ? When should I set it to TRUE and when to FALSE? > > No idea :) I guess you should leave it FALSE and rely on > g_main_loop_run() to turn this on for you. > > John _______________________________________________ gtk-list mailing list gtk-list@xxxxxxxxx http://mail.gnome.org/mailman/listinfo/gtk-list
