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0 pointscosmos00721y ago0 comments

I found another, possibly simpler solution.

The functions (sh-fd-stdin) (sh-fd-stdout) and (sh-fd-stderr) return the integer file descriptors that a schemesh builtin should use to perform I/O.

With them, you can do

  true (lambda () (lisp-expr-writes-to-fd (sh-fd-stdout))) | grep foo | true (lambda () (lisp-expr-reads-from-fd (sh-fd-stdin)))

It should work :)

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3 comments · 1 top-level

pama1y ago· 2 in thread

Could this be abstracted enough with the right macros to make a subset of useful lisp commands play well with the shell? It could be a powerful way to extend the shell for interactive use.

cosmos0072OP1y ago

Yes, that's definitely feasible.

I am currently working on it, the macro will be named (shell-expr) and replace the current experimental (shell-test)

cosmos0072OP1y ago

[UPDATE] (shell-expr) is ready and kicking :)

Now you can write

  (import (schemesh all))

  (shell-expr (lisp-expression-writing-to-sh-fd-stdout)) | some-shell-command-and-args | (shell-expr (lisp-expression-reading-from-sh-fd-stdin))

An example of such expressions is: For writing to sh-fd-stdout,

  (fd-write (sh-fd-stdout) (string->utf8b "hello\n"))

For reading from sh-fd-stdin,

  (display (utf8b-bytespan->string (fd-read-until-eof (sh-fd-stdin))))

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