Maybe textConnection()
is what you want here:
R> zz <- read.table(textConnection("a b c
1 11 foo
2 12 bar
3 13 baz
4 14 bar
5 15 foo"), header=TRUE)
R> zz
a b c
1 1 11 foo
2 2 12 bar
3 3 13 baz
4 4 14 bar
5 5 15 foo
R>
It allows you to treat the text as a “connection” from which to read. You can also just copy and paste, but access from the clipboard is more dependent on the operating system and hence less portable.