cpimport.bin include the possibility of custom directory for .bad and .err files.
If cpimport will be called manually, .bad and .err files will be saved in the directory like the import files.
If for some reason (policy etc.) only read access is possible, .bad and .err files can't be written.
So a custom directory for writing the logs would be good.
This option already exists in cpimport.bin
And already declared in we_bulkload.h
So maybe an easy solution would be to add this option also in cpimport and set the errordir like cpimport.cpp