How to pass in command line arguments when using ideone

0 votes
To test some C++ and Python programmes, I'm using the ideone online interpreter.

Instead of using the STDIN input, how do I specify command line arguments?
Jun 6, 2022 in C++ by Nicholas
• 7,760 points
1,010 views

1 answer to this question.

0 votes

It appears that you won't be able to, however a fast hack should suffice:

static char * const ARGV[] = { "myprog", "hello", "world", NULL };

int main(int argc, char * argv[])
{
    argc = 3;
    argv = ARGV;

    // ...
}

Alternatively, you may transform the standard input to args:

#include <vector>
#include <string>
#include <iterator>
#include <iostream>

std::vector<char *> fabricate(std::vector<std::string> & v)
{
    std::vector<char *> res(v.size() + 1, NULL);
    for (std::size_t i = 0; i != v.size(); ++i) { res[i] = &v[i][0]; }
    return res;
}

std::vector<std::string> args_vector((std::istream_iterator<std::string>(std::cin)), std::istream_iterator<std::string>());

std::vector<char *> argv_vector = fabricate(args_vector);


int main(int argc, char * argv[])
{
    argc = args_vector.size();
    argv = argv_vector.data();

    // ...
}
answered Jun 21, 2022 by Damon
• 4,960 points

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