handling warning messages

Is there any way to store the value of warnings but avoid printing them?

A simplified example:

out <- c(0.2,0.3,0.4)
var <- c(2,3,4)
outcome <- glm(out ~ var, family=binomial())

Warning message:
non-integer #successes in a binomial glm! in: eval(expr, envir, enclos)

I don't like the warning printed, 
but I would like to be able to check it's value after the top-level function 
has completed and than decide weather to print it or not.

Thanks,

Sigal Blay
Statistical Genetics Working Group
Department of Statistics and Actuarial Science
Simon Fraser University