Re: [Bug-ddrescue] user-interface suggestions

[Antonio Diaz Diaz]

Richard Neill wrote:
> May I suggest a few more sentences of documentation would help? In the 
> common case (a modern Linux or BSD system), is it fair to say that -d 
> will work? If ddrescue is invoked with -d, but direct access isn't 
> possible, will it fail gracefully, or will bad things happen? How can I 
> find out whether the hardware block size is correctly set?

Yes. I'll try to answer these questions in the manual.


> * When should -d as opposed to -n be used?
>   I think this is what you refer to as an art.

This is not an art at all. -d and -n are totally unrelated options. You 
can combine them as you like. -d determines how to access the data, 
while -n makes ddrescue stop after the trimming pass.


> * Is it appropriate to use -d at all? Are the block sizes correct? Does
>   my system support this?
>   That's what I suggest should be automated.

Here is where the art resides. -d may be faster or slower than cached 
reads. There may be several valid combinations of block size / read 
size. All of it depending on the type of medium and OS.


> That's probably unnecessary here, but I think that USR1 should be 
> trapped and *ignored* rather than treated the same as SIGINT.

OK. Ignoring it is as easy as handling it.


Regards,
Antonio.