base backup and tar problems with disappearing files.

Dear Friends,

While taking online basebackup we ignore tar exit codes of 1 .
However under certain circumstances tar exits we code '2' which
stands for 'Fatal Errors' . Eg in case of "Cannot stat: No such file or
directory"
encountered while taking backup of the pgdatadir . My question is
can we ignore such errors of "vanishing files" ? is it normal ?
I think the situation is arising because some table which were created
before start of backup were dropped during the backup. But that is
quite normal also.

regds
mallah.

tar: Removing leading `/' from member names
tar: /mnt/disk1/pgdatadir/base/16399/445408706: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/301908133: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/51363916: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/51363949: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/51369062: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/51369071: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/865944857: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/810163513: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/843721621: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/861272781: Cannot stat: No such file or
directory
tar: /mnt/disk1/pgdatadir/base/16399/861272782: Cannot stat: No such file or
directory
tar: /mnt/disk1/pgdatadir/base/16399/861272783: Cannot stat: No such file or
directory
tar: /mnt/disk1/pgdatadir/base/16399/861272784: Cannot stat: No such file or
directory
tar: /mnt/disk1/pgdatadir/base/16399/865944127: file changed as we read it
tar: /mnt/disk1/pgdatadir/base/16399/861272783_vm: Cannot stat: No such file
or directory
tar: /mnt/disk1/pgdatadir/base/16399/861272781_vm: Cannot stat: No such file
or directory
tar: /mnt/disk1/pgdatadir/base/pgsql_tmp/pgsql_tmp7934.6: file changed as we
read it
tar: Error exit delayed from previous errors
Dying because tar exited with an exit code: 2 not in {0, 1}