diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/stdlib/doc/src/gen_statem.xml | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml index b20abbea5d..d19602b67c 100644 --- a/lib/stdlib/doc/src/gen_statem.xml +++ b/lib/stdlib/doc/src/gen_statem.xml @@ -1685,6 +1685,19 @@ handle_event(_, _, State, Data) -> It is recommended to use an atom as <c>Reason</c> since it will be wrapped in an <c>{error,Reason}</c> tuple. </p> + <p> + Also note when upgrading a <c>gen_statem</c>, + this function and hence + the <c>Change={advanced,Extra}</c> parameter in the + <seealso marker="sasl:appup"><c>appup</c></seealso> file + is not only needed to update the internal state + or to act on the <c>Extra</c> argument. + It is also needed if an upgrade or downgrade should change + <seealso marker="#type-callback_mode"><em>callback mode</em></seealso>, + or else the callback mode after the code change + will not be honoured, + most probably causing a server crash. + </p> </desc> </func> |