process trace triggered by sequential trace token

Dmitriy Kargapolov <>
Fri Feb 4 03:46:50 CET 2011


On Wed, Feb 2, 2011 at 10:04 AM, Dmitriy Kargapolov <
> wrote:

> Hi All,
> I'd like to trace gen_server body execution, not for all calls, but for
> particular one.
> Is there a way to enable trace for the process by received (and matched)
> message "contaminated" by trace token? (And disable it at the end of message
> processing). I know there is a way to turn sequential trace by matching
> regular function call, but I need things to go in reverse order...
> Thanks.
>

Just want to let everybody know that this can be achieved by using
is_seq_trace as a guard in match specification. It could be used to allow
function trace only when trace token is set, or, to trigger silent mode to
allow/disable further trace messages. See
http://www.erlang.org/doc/apps/erts/match_spec.html for details.


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