[CentOS] gtar compression achieved

On Wednesday, February 01, 2012 09:18:08 AM Alan McKay wrote:
> The basic problem is that I know how much data is there to begin with but I
> don't know how much room it took up on the tape so I have no idea how much
> room is left on the tape.

What I would do is use the '-' special filename to pipe the uncompressed tar to stdout, pipe to the compressor of choice, then pipe to tee, and have one branch of the tee go to the tape and the other branch go to a program to count bytes.