Since you mention SQLite, check out the MBS plugin. They mention the ability to connect with SQLite and appear to have some basic functions for text file manipulation. I don't have personal experience with this plugin, but sounds like it is worth you having a look.
The other plugin that I am familar with for text functions is Troi File. It has been around for a very long time and has worked really well in my experience.
From what I can tell, the MBS plugin does not read or write directly to text files, but it does look like you can connect directly to SQLite database.
I've seen Troi File plugin and it looks pretty capable and what I'm looking for.
I can highly recommend the Troi File plug-in. I've been using it a long time.
+1 for Troi File. Very flexible, lots of functions, and very reliable.
Been using it for years.
Peace, love & brown rice,
FileMaker + Web: Design, Develop & Deploy
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One Part Harmony <http://www.onepartharmony.com/>
Austin, Texas • USA
Thank you for the suggestions. I will give it a try.
And ScriptMaster from 360works. It's free and you can extend it too.