How to make this pipe work in c++?

Question

I am programming a shell in c++. It needs to be able to pipe the output from one thing to another. For example, in linux, you can pipe a textfile to more by doing cat tex

Answer 1

fopen() is not used to create pipes. It can be used to open the file descriptor, but it is not necessary to do so.

Pipes are created with the pipe(2) call, before forking off the process. The subprocess has a little bit of file descriptor management to do before execing the command. See the example in pipe's documentation.