When exporting, dont overwrite the output file if it already exists

[siliconpi]

A simple prompt or renaming of the output file would be more appropriate rather than overwriting the data that already exists.

[rusq]

Hey @siliconpi , thanks, that's a good idea. I actually never thought of it as It's a default behaviour for many *nix utilities - but I can see that from the UX perspective it might be frustrating if you're not expecting this to happen.

[rusq]

The change is now in master, it's going to be released in v3.1.7