Some cpdf commands write text to standard output, or read text from the command line or configuration files. These are:
-info
-list-bookmarks
-set-author et al.
-list-annotations
There are three options to control how the text is interpreted:
-utf8
-stripped
-raw
Add -utf8 to use Unicode UTF8, -stripped to convert to 7 bit ASCII by dropping any high characters, or -raw to perform no processing. The default is -stripped.