But are all tapes operations non-blocking? The most efficient way
seems to be to perform all operations in blocking mode, meaning that
the next operation is performed after finnishing the current one.

Either (1) amtape does everything non-blocking, meaning that the sleep
time must be an upper bound of the worst case sequence of operations,
or (2) amtape does everything in blocking mode, but adds a sleep time
in case commands return before the completion of the operation.

What is the case with amanda?

What happens if one sets sleep to zero?

Cheers,

Rodrigo

-- 

*** Rodrigo Martins de Matos Ventura <yoda AT isr.ist.utl DOT pt>
***  Web page: http://www.isr.ist.utl.pt/~yoda
***   Teaching Assistant and PhD Student at ISR:
***    Instituto de Sistemas e Robotica, Polo de Lisboa
***     Instituto Superior Tecnico, Lisboa, PORTUGAL
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