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Description

Creates a tar archive.

The basedir attribute is the reference directory from where to tar.

This task is a directory based task and, as such, forms an implicit Fileset. This defines which files, relative to the basedir, will be included in the archive. The tar task supports all the attributes of Fileset to refine the set of files to be included in the implicit fileset.

In addition to the implicit fileset, the tar task supports nested filesets. These filesets are extended to allow control over the access mode, username and groupname to be applied to the tar entries. This is useful, for example, when preparing archives for Unix systems where some files need to have execute permission.

Early versions of tar did not support path lengths greater than 100 characters. Modern versions of tar do so, but in incompatible ways. The behaviour of the tar task when it encounters such paths is controlled by the longfile attribute. If the longfile attribute is set to fail, any long paths will cause the tar task to fail. If the longfile attribute is set to truncate, any long paths will be truncated to the 100 character maximum length prior to adding to the archive. If the value of the longfile attribute is set to omit then files containing long paths will be omitted from the archive. Either option ensures that the archive can be untarred by any compliant version of tar. If the loss of path or file information is not acceptable, and it rarely is, longfile may be set to the value gnu. The tar task will then produce a GNU tar file which can have arbitrary length paths. Note however, that the resulting archive will only be able to be untarred with GNU tar. The default for the longfile attribute is warn which behaves just like the gnu option except that it produces a warning for each file path encountered that does not match the limit.

This task can perform compression by setting the compression attribute to "gzip" or "bzip2".


next up previous contents index
Next: Parameters Up: Tar Previous: Tar   Contents   Index
Andrew Marlow 2003-07-08