[Pw_forum] Compatibility among different versions

[Tianshu Li]

Dear QE users and developers,

I am curious if there might be a compatibility problem in file I/O among
different versions, because when I used the post-processing code, for
instance, pp.x in the latest version (v.3.1.1) to read the .save file
generated in the previous version (v.3.0), it complained it could not
find the .save file. The message is like:

from pp_check_file : error #         1
file  **********************/**.save not found.

I noticed that in the latest version the new function "pp_check_file"
was added to the xml_io_base.f90. This might be what gives the problem,
but I am not very sure of that. Thanks

Tianshu Li