Pipes and Redirection

[jorinvo]

We already have some chapters prepared for our game to teach about pipes | and redirection< / >.

This can be implemented in a generic way in the .run() system method.

The command interface is already designed in a way to allow streaming of input and output.

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[LordRatte]

Hi. Is there documentation on how to implement piping?

[jorinvo]

Hi @LordRatte! Thanks for your interest. Would you like to help adding pipes to bash-emulator?

To implement pipes, the run() method needs to be modified to detect the | pipes in the input string and it would need to initialize multiple commands, chaining their output and input together.

Input is described here but currently not implemented in any of the commands.

The only existing command that can use input is cat. To add input support to cat, it would need to detect if there are no arguments passed and in that case return the input and close callbacks.

To summarize, only run and cat need to be modified. After pipes are implemented you should be able to run a command like cat myfile.txt | cat | cat.

Please let me know if you have any questions!

[LordRatte]

Hi, jorinvo. Sorry, I misunderstood. I thought you were saying that it was already available to be used. I would love to help out but I wouldn't even know how to start.

[jorinvo]

Good news! I added the pipes functionality.
@LordRatte you can try it at https://trybash.github.io/bash-emulator/
with some command like ls -l | cat -n.

[LordRatte]

Hey, that's pretty cool @jorinvo . Thanks, man.