-1

I want to take an input, a bash command, and be able to execute that input from my CPP program. This is for school and we are not allowed to use "system" so I do not know any other way to do this. Also, the program can take up to 3 commands via pipe. I've looked up how to do this but it just gets more confusing. If there are any resources or a question similar to this that has been answered please link. Thanks.

Improve this question
5
  • 4
    There's a whole family of exec functions you can use. Commented Apr 1, 2021 at 21:44
  • 1
    This Commented Apr 1, 2021 at 21:44
  • Won't work for intrinsic bash commands of course, only executables. But you can also run bash directly using execxy() and pass commands via a pipe for example. Commented Apr 1, 2021 at 21:47
  • Does this answer your question? It uses the example of executing echo from the program. Commented Apr 1, 2021 at 21:47
  • I apologize: I marked the wrong question as duplicate. But there are many questions on SO that can answer this. eg: stackoverflow.com/questions/5094063/… Commented Apr 1, 2021 at 22:21

1 Answer 1

Reset to default
0

Here is a similar question.

Basically, for the shell part, you are going to use fork and some form of exec (e.g., execve) to get that to execute.

For pipes, you're going to have to use the pipe command in C++, which will allow you to write and read from the pipe from separate children (in your case, up to two pipes, so you can create a 2x2 array of file descriptors, as a normal pipe is just a 2 element array). You should write the output of one program into the correct pipe and read it from the pipe in the next child once the first terminates.

Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.