gen_fsm模块¶

说明:

OTP 20 [erts-9.0]之后变成Deprecated
被替换为gen_statem

有限状态机:finite state machine

行为函数与回调函数的关系:

gen_fsm module                    Callback module
--------------                    ---------------
gen_fsm:start
gen_fsm:start_link                -----> Module:init/1

gen_fsm:stop                      -----> Module:terminate/3

gen_fsm:send_event                -----> Module:StateName/2

gen_fsm:send_all_state_event      -----> Module:handle_event/3

gen_fsm:sync_send_event           -----> Module:StateName/3

gen_fsm:sync_send_all_state_event -----> Module:handle_sync_event/4

-                                 -----> Module:handle_info/3

-                                 -----> Module:terminate/3

-                                 -----> Module:code_change/4

Module:init(Args) -> Result¶

Args = term()
Result = {ok,StateName,StateData} | {ok,StateName,StateData,Timeout}
  | {ok,StateName,StateData,hibernate}
  | {stop,Reason} | ignore
 StateName = atom()
 StateData = term()
 Timeout = int()>0 | infinity
 Reason = term()

enter_loop/4/5/6¶

enter_loop(Module, Options, StateName, StateData)
enter_loop(Module, Options, StateName, StateData, FsmName)
enter_loop(Module, Options, StateName, StateData, Timeout)
enter_loop(Module, Options, StateName, StateData, FsmName, Timeout)
类型:
Module = atom()
Options = [Option]
 Option = {debug,Dbgs}
  Dbgs = [Dbg]
   Dbg = trace | log | statistics| {log_to_file,FileName} | {install,{Func,FuncState}}
   StateName = atom()
StateData = term()
FsmName = {local,Name} | {global,GlobalName} | {via,Module,ViaName}
 Name = atom()
 GlobalName = ViaName = term()
Timeout = int() | infinity