Parallel gnu passing arguments in shell script

Question

I would like to pass an argument to a c++ program in a shell script that just prints it to the console. However, I want to use gnu parallel to do it. At the moment I have a shell script,

#!/bin/sh
parallel -k echo ::: 1 2 3 > cTest
parallel ./hello :::: cTest

where I first create a file 'cTest' that contains the items that will be passed to the executable 'hello'.

At the moment, the above just prints blank spaces. I have tried doing,

parallel echo :::: cTest | ./hello

but this just prints '2' (I am also concerned that the above won't be in parallel).

Does anyone know how to get this working?

Answer 1

This works for me:

#!/bin/sh

cat <<EOF >hello.cpp

#include <iostream>

int main(int argc, char** argv) {
  std::cout << "Have " << argc << " arguments:" << std::endl;
  for (int i = 0; i < argc; ++i) {
    std::cout << argv[i] << std::endl;
  }
}

EOF
g++ hello.cpp -o hello

parallel -k echo ::: 1 2 3 > cTest
parallel ./hello :::: cTest