bug#22768: Crash safety

[Antonio Diaz Diaz]

Paul Eggert wrote:
> Thanks for reporting the problem. It's annoying that gzip must invoke 
> fsync, as that's way overkill compared to the write-ordering that is 
> needed and fsync will slow gzip down, but I don't see any safe and 
> reasonably portable alternative

I 100% agree.

I am considering a different approach for lzip; adding a new option, say 
'-y, --fsync', to call fsync when acting in-place. This provides safety 
to those needing it without slowing down the work of everybody else. 
Especially of those (de)compressing a lot of replaceable files in-place.

(Ddrescue provides the option '-y, --synchronous' because calling fsync 
by default is too slow).

What do you think?