This feature -- which, like API, is not for those without a tame programmer to help -- is found under Main Settings | Advanced.
The point of it…
I cannot know which criteria you have in processing your texts, other than the criteria already set up (the choice of texts, of search-word, etc.) You might need to do some specialised checks or alteration of data before it enters the WordSmith formats. For example, you might need to lemmatise a word according to the special requirements of your language.
This function makes that possible. If for example you have chosen to filter concordances, as Concord processes your text files, every time it finds a match for your search-word, it will call your .dll file. It'll tell your own .dll what it has found, and give it a chance to alter the result or tell Concord to ignore this one.
How to do it…
Choose your .dll file (it can have any filename you've chosen for it) and check one or more of the options in the Advanced page. You will need to call standard functions and need to know their names and formats. It is up to you to write your own .dll program which can do the job you want. This can be written in any programming language (C++, Java, Pascal, etc.).
An example for lemmatising a word in WordList
The following DLL is supplied with your installation, compiled & ready to run.
Your .dll needs to contain a function with the following specifications
original : pointer;
language_identifier : DWORD;
is_Unicode : WordBool) : pointer; stdcall;
The language_identifier is a number corresponding to the language you're working with. See List of Locale ID (LCID) Values as Assigned by Microsoft .
So the "original" (sent by WordSmith) can be a PANSICHAR (7 or 8-bit) or a PWIDECHAR (16-bit Unicode) and the result which your .dll supplies can point to
a) nil (if you simply do not want the original word in your list)
b) the same PANSICHAR/PWIDECHAR if it is not to be changed at all
c) a replacement form
Here's an example where the source text was
Today is Easter Day.