Support for mounted tar files

[tedgin]

Using the iCommand imcoll, a tar data object can be mounted as a collection, allowing other iCommands to transparently access the contents of the tar data object. For example,

prompt> ls set
file1  file2
prompt> tar -c -C set -f set.tar .
prompt> iput -D tar set.tar /zone/home/user
prompt> imkdir /zone/home/user/set
prompt> imcoll -m tar /zone/home/user/set.tar /zone/home/user/set
prompt> ils set
  file1
  file2

It would be nice if davrods could provide WebDAV support for mounted tar data objects. At the moment, davrods allows navigation of the directories in the mounted tar data object, but it doesn't allow any files to be downloaded. When a download is attempted, it fails and logs a rcDataObjLseek failed: -19000 = SYS_FILE_DESC_OUT_OF_RANGE error.