[R] reading non-existent files

[ripley@stats.ox.ac.uk]

On Tue, 28 Jan 2003 Christian.Stratowa at vie.boehringer-ingelheim.com wrote:

> I would like to read all files from a directory, the files have names
> "myname0001.txt" etc. I paste the directory plus file names and
> use "read.delim()".
> My problem is that some file names are missing, so I get an error
> and my program stops.

How can some of `all files from a directory' be missing?  Why not read 
them via e.g. list.files()?

> Is there a way to check for a null pointer analogous to C, so that
> I can simply skip non-existent filenames?

?file.exists

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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