[R] t-test or conf interval with known variance?

[Thomas Hopper]

Hello,

Is there a built-in test in R for hypothesis testing with samples of 
known variance?

For example, I've got a set of data, a mean to compare against, and a 
known variance, and I want to determine the p-value for which I can 
reject the null hypothesis (mu_1 = mu_0) and accept the alternative 
(mu_1 > mu_0). I've found that JMP and Minitab can both do this (in 
JMP, it's a one-sided confidence interval in the Distribution 
platform), but I haven't figured out how to do such a test in R.

Thanks,

Tom