[R] Can scan() detect end-of-file?

[Jeff Newmiller]

This is a problem in C as well... and the solution is to read the lines yourself and then give those lines to scan. 
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Sent from my phone. Please excuse my brevity.

On October 15, 2015 1:16:58 PM PDT, William Dunlap <wdunlap at tibco.com> wrote:
>I would like to read a connection line by line with scan but
>don't know how to tell when to quit trying.  Is there any
>way that you can ask the connection object if it is at the end?
>
>E.g.,
>
>t <- 'A "Two line\nentry"\n\n"Three\nline\nentry" D E\n'
>tfile <- tempfile()
>cat(t, file=tfile)
>tcon <- file(tfile, "r") # or tcon <- textConnection(t)
>scan(tcon, what="", nlines=1)
>#Read 2 items
>#[1] "A"               "Two line\nentry"
>> scan(tcon, what="", nlines=1)  # empty line
>#Read 0 items
>#character(0)
>scan(tcon, what="", nlines=1)
>#Read 3 items
>#[1] "Three\nline\nentry" "D"                  "E"
>scan(tcon, what="", nlines=1) # end of file
>#Read 0 items
>#character(0)
>scan(tcon, what="", nlines=1) # end of file
>#Read 0 items
>#character(0)
>
>I am reading virtual line by virtual line because the lines
>may have different numbers of fields.
>
>Bill Dunlap
>TIBCO Software
>wdunlap tibco.com
>
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