[CM] What is the "normal" way to handle errors for side effect functions in Scheme?

[bil at ccrma.Stanford.EDU]

That code looks fine to me.  On the scheme side you'll want
a catch somewhere.  The other common choice is to return some
error indication, and then the scheme side has to check for
that.  All the s7 C-library tie-ins (like libgsl) call s7_error.