[R] saving warning messages

[vito muggeo]

Dear all,
is it possible to save warning messages in the object created by any
function causing the warning message itself?

For instance coxph() in survival package fits Cox regression model and
returns the fitted model with possible warning messages if some problems
occur in fitting. However sometimes the warning messages may be meaningless
and the fitted model to be valid at all.
Therefore I would like the warning msg to be attached in the returned
object, i.e. to have something like
obj<-coxph(.... #print warning message
is.null(obj$warning)
> FALSE

Using par(warn=2) causes the warnings messages to be considered as error and
it is not what I want.

many thanks for your time,

vito