Message-ID: <Pine.A41.4.61b.0505120710480.308540@homer10.u.washington.edu>
Date: 2005-05-12T14:17:32Z
From: Thomas Lumley
Subject: R2.1.0: Bug in list.files
In-Reply-To: <42831861.1070103@columbia.edu>
On Thu, 12 May 2005, Suresh Krishna wrote:
> Is that the entire story ? I tried this with yesterday's patched version
> (windows xp) and found:
>
>> list.files(getwd(),"*.txt",full=T)
> Error in list.files(path, pattern, all.files, full.names, recursive) :
> invalid 'pattern' regular expression
>
>> list.files(getwd(),'.txt',full=T)
> [1] "C:/Documents and Settings/suresh/BDE_SysInfo.txt"
> [2] "C:/Documents and Settings/suresh/dxva_sig.txt"
>
> Replacing "*.txt" with '*.txt' seems to do "something".
>
It finds any file name containing the substring txt beginning anywhere
except the first letter. Now, this is exactly what *.txt used to do, so in
that sense it is equivalent, but it probably isn't what you wanted. The
pattern argument to list.files isn't a Windows wildcard expression. It
never has been a Windows wildcard expression. It just so happens that
".txt" is also a valid regular expression, but one that means something
different from the Windows wildcard expression "*.txt".
-thomas