ThreadGroup
provides a means of keeping track of a number of
threads as a group. A Thread
can belong to only one
ThreadGroup
at a time; adding a thread to a new group will
remove it from any previous group.
Newly created threads belong to the same group as the thread from which they were created.
Adds the given thread to this group, removing it from any other group to which it may have previously belonged.
puts "Initial group is #{ThreadGroup::Default.list}" tg = ThreadGroup.new t1 = Thread.new { sleep } t2 = Thread.new { sleep } puts "t1 is #{t1}" puts "t2 is #{t2}" tg.add(t1) puts "Initial group now #{ThreadGroup::Default.list}" puts "tg group now #{tg.list}"
produces:
Initial group is #<Thread:0x401bdf4c> t1 is #<Thread:0x401b3c90> t2 is #<Thread:0x401b3c18> Initial group now #<Thread:0x401b3c18>#<Thread:0x401bdf4c> tg group now #<Thread:0x401b3c90>
static VALUE thgroup_add(VALUE group, VALUE thread) { rb_thread_t *th; struct thgroup *data; rb_secure(4); GetThreadPtr(thread, th); if (OBJ_FROZEN(group)) { rb_raise(rb_eThreadError, "can't move to the frozen thread group"); } Data_Get_Struct(group, struct thgroup, data); if (data->enclosed) { rb_raise(rb_eThreadError, "can't move to the enclosed thread group"); } if (!th->thgroup) { return Qnil; } if (OBJ_FROZEN(th->thgroup)) { rb_raise(rb_eThreadError, "can't move from the frozen thread group"); } Data_Get_Struct(th->thgroup, struct thgroup, data); if (data->enclosed) { rb_raise(rb_eThreadError, "can't move from the enclosed thread group"); } th->thgroup = group; return group; }
Prevents threads from being added to or removed from the receiving
ThreadGroup
. New threads can still be started in an enclosed
ThreadGroup
.
ThreadGroup::Default.enclose #=> #<ThreadGroup:0x4029d914> thr = Thread::new { Thread.stop } #=> #<Thread:0x402a7210 sleep> tg = ThreadGroup::new #=> #<ThreadGroup:0x402752d4> tg.add thr
produces:
ThreadError: can't move from the enclosed thread group
static VALUE thgroup_enclose(VALUE group) { struct thgroup *data; Data_Get_Struct(group, struct thgroup, data); data->enclosed = 1; return group; }
Returns true
if thgrp is enclosed. See also #enclose.
static VALUE thgroup_enclosed_p(VALUE group) { struct thgroup *data; Data_Get_Struct(group, struct thgroup, data); if (data->enclosed) return Qtrue; return Qfalse; }
Returns an array of all existing Thread
objects that belong to
this group.
ThreadGroup::Default.list #=> [#<Thread:0x401bdf4c run>]
static VALUE thgroup_list(VALUE group) { VALUE ary = rb_ary_new(); struct thgroup_list_params param; param.ary = ary; param.group = group; st_foreach(GET_THREAD()->vm->living_threads, thgroup_list_i, (st_data_t) & param); return ary; }