Found in 3 comments
davidw · 2018-05-13 · Original thread
Tcl's C API is very nice, and makes it easy to either integrate Tcl into a larger C app, or write bits and pieces of C as Tcl commands.

I helped work on the 2nd edition of this book, which I think is still fairly relevant:

davidw · 2015-07-28 · Original thread
There is also an updated version out (with my name on the cover, to boot:-)

Although even that is not super recent.

Tcl's C API is very pleasant to work with, and its C code is a good read - except for the regex stuff, which are the first few files you'd see in an alphabetical listing.

davidw · 2013-10-15 · Original thread
Actually, internally, everything is not a string, and has not been that way since... 10+ years. Everything is representable as a string, though.

I actually like Tcl quite a bit even if I don't use it much these days: (See the cover for all of the authors' names :-)

View this Book on Amazon