[erlang-questions] net_adm:ping_list/1 and the scary comment above it

[Martin Schürrer]

Was looking through the Erlang/OTP source yesterday and found
net_adm:ping_list/1 which isn't documented but has a really scary comment:

https://github.com/erlang/otp/blob/maint/lib/kernel/src/net_adm.erl#L117-L132

%% A common situation in "life" is to have a configuration file with a list
%% of nodes, and then at startup, all nodes in the list are ping'ed
%% this can lead to no end of troubles if two disconnected nodes
%% simultaneously ping each other.
%% Use this function in order to do it safely.
%% It assumes a working global.erl which ensures a fully
%% connected network.
%% Had the erlang runtime system been able to fully cope with
%% the possibility of two simultaneous (unix) connects, this function would
%% merley  be lists:map({net_adm, ping}, [], Nodelist).
%% It is also assumed, that the same (identical) Nodelist is given to all
%% nodes which are to perform this call (possibly simultaneously).
%% Even this code has a flaw, and that is the case where two
%% nodes simultaneously and without *any* other already
%% running nodes execute this code. :-(

It's been in there since at least R13B03 when Erlang moved to git.

Can someone enlighten me if I should take that warning seriously?

Kind regards,
Martin Schuerrer
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