Sometimes, pv(1) doesn't help. For example, `tar cf - foo | bzip2 -9v >foo.tar.bz2'. You don't know the size of the data that needs to pass down the pipe. Bu

Sometimes, pv(1) doesn't help. For example, `tar cf - foo | bzip2 -9v >foo.tar.bz2'. You don't know the size of the data that needs to pass down the pipe. But I sometimes find watching tar(1) open the files to read is handy; `strace -e trace=open $(pidof tar)'.