rb_thread_atfork_before_exec  336 include/ruby/intern.h void rb_thread_atfork_before_exec(void);
rb_thread_atfork_before_exec 4461 io.c               rb_thread_atfork_before_exec();
rb_thread_atfork_before_exec 2170 process.c          rb_thread_atfork_before_exec();