diff options
Diffstat (limited to 'lib/stdlib/doc')
| -rw-r--r-- | lib/stdlib/doc/src/gen_fsm.xml | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/lib/stdlib/doc/src/gen_fsm.xml b/lib/stdlib/doc/src/gen_fsm.xml index 719ab2b558..691a039e34 100644 --- a/lib/stdlib/doc/src/gen_fsm.xml +++ b/lib/stdlib/doc/src/gen_fsm.xml @@ -562,6 +562,13 @@ gen_fsm:sync_send_all_state_event -----> Module:handle_sync_event/4 <v>Extra = term()</v> </type> <desc> + <note> + <p>This callback is optional, so callback modules need not export it. + If a release upgrade/downgrade with <c>Change={advanced,Extra}</c> + specified in the <c>appup</c> file is made when <c>code_change/4</c> + isn't implemented the process will crash with an <c>undef</c> exit + reason.</p> + </note> <p>This function is called by a <c>gen_fsm</c> process when it is to update its internal state data during a release upgrade/downgrade, that is, when instruction <c>{update,Module,Change,...}</c>, @@ -686,6 +693,13 @@ gen_fsm:sync_send_all_state_event -----> Module:handle_sync_event/4 <v> Reason = normal | term()</v> </type> <desc> + <note> + <p>This callback is optional, so callback modules need not + export it. The <c>gen_fsm</c> module provides a default + implementation of this function that logs about the unexpected + <c>Info</c> message, drops it and returns + <c>{next_state, StateName, StateData}</c>.</p> + </note> <p>This function is called by a <c>gen_fsm</c> process when it receives any other message than a synchronous or asynchronous event (or a system message).</p> @@ -899,6 +913,11 @@ gen_fsm:sync_send_all_state_event -----> Module:handle_sync_event/4 <v>StateData = term()</v> </type> <desc> + <note> + <p>This callback is optional, so callback modules need not + export it. The <c>gen_fsm</c> module provides a default + implementation without cleanup.</p> + </note> <p>This function is called by a <c>gen_fsm</c> process when it is about to terminate. It is to be the opposite of <seealso marker="#Module:init/1"><c>Module:init/1</c></seealso> |