z3bra Wrote:The shell's job is to handle IPC, and that's it. Text processing is done by the processes themselves, the shell only connects outputs to the next process input.

In theory, yes. In practice, virtually all shell scripts deal with text processing and filtering by calling grep, sed, awk and the others. These text processing programs are pointless without a shell to call them, and a shell is pointless without text processing programs or routines to handle the output of the other programs it is calling.

I am making an awk-like program. Shell pipes are just a small convenience, they don't add too much complexity.

The challenge that I'm facing is to make it work on a stream of text. Sed and awk operate on lines, structural regular expressions operate on characters or the whole text.