(tar_timespec_cmp): New function. Wrapper over
timespec_cmp using the timespec precision provided by the
current archive format.
* src/common.h (tar_timespec_cmp): New declaration.
* src/compare.c (diff_file): Use tar_timespec_cmp.
* src/extract.c (file_newer_p): Likewise.
* src/update.c (update_archive): Likewise.
* tests/truncate.at: Reverted changes
* tests/update.at: Reverted changes
1-second boundaries. This prevents tests from failing on hosts
like Solaris 8 that have nanosecond-resolution file time stamps.
* tests/update.at: Likewise.