[R] problem of unix package installation, following code no response: install.packages("packagename", dependecise=TRUE)

[Yong Wang]

Dear list

I am trying installing a package under unix, the command as below
works in some case but not some other cases, the primary
syndrome is R will stop there  with a message: (say I am trying to
install the package SASxport)

###########################
Warning in install.packages("SASxport", dependencies = TRUE) :
  argument 'lib' is missing: using
'/usr/home/d/068/wangyong/R/x86_64-unknown-linux-gnu-library/2.7'
Warning: unable to access index for repository
http://lib.stat.cmu.edu/R/CRAN/src/contrib
#############################

My internet connection has no problem, why this happen?
or can you suggest some more options or examples to follow for package
installation under unix?


Thank you

will