R help - May 2010 - Error in untar2(tarfile, files, list, exdir) : unsupported entry type ‘x’

Hi R gurus,

I'm getting the following error when trying to build and install an R
package:

Error in untar2(tarfile, files, list, exdir) : unsupported entry type ?x?

I build the package like so:
R --no-init-file CMD build mypackage

Then try to install it:
sudo R --no-init-file CMD INSTALL mypackage.tar.gz

...which dies with the above error. I can extract the archive fine
with tar -zxf, so I don't think the file has problems.

R version 2.11.0 (2010-04-22)
OSX 10.6.3

Any hints would be greatly appreciated! Thanks,

-- chris

Hi,

I'm starting to think this is a Mac OS X Snow Leopard specific issue.
The GNU docs on the tar format say the type flag 'x' means this:

#define XHDTYPE  'x'            /* Extended header referring to the
                                   next file in the archive */

Maybe, OSX is putting some bad juju in my files causing them to have
these extended headers?? Aaarg!

-chris

For posterity, this thread was continued on the R-SIG-Mac mailing list
under the same subject. Prof. Brian Ripley was kind enough to point
out an easy work around:

R CMD INSTALL now uses the internal untar() in package utils:
this ensures that all platforms can install bzip2- and
xz-compressed tarballs. In case this causes problems (as it
has on some Windows file systems when run from Cygwin tools)
it can be overridden by the environment variable
R_INSTALL_TAR: setting this to a modern external tar program
will speed up unpacking of large (tens of Mb or more) tarballs.

I suspect that the origin of the non-standard tar block types was that
user accounts and groups on my Mac are managed by Active Directory.
The same commands work on another Snow Leopard Mac with locally
managed accounts.

-chris