How to this SAS transport file in R?

You didn't tell us your OS.  That is a binary file, and from 
?download.file:

     mode: character.  The mode with which to write the file. Useful
           values are ?"w"?, ?"wb"? (binary), ?"a"? (append) and ?"ab"?.
           Only used for the ?"internal"? method.

Only on Windows are the binary modes different, so it looks like you
forgot mode="wb".

Dear All,

I try to read the SAS transport file in R, but it shows error. Please help!
I am using R 2.11.1

library(foreign)
download.file("http://isites.harvard.edu/fs/docs/icb.topic35387.files/demo_c.xpt","C:/Desktop/demo_c.xpt")
sasxport <- read.xport("C:/Desktop/demo_c.xpt")

Error in lookup.xport(file) : file not in SAS transfer format

[...]

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Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
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