Convert command line argument to string

Question

I have a program that reads hard-coded file-path and I want to make it read file-path from command line instead. For that purpose I changed the code like this:

#         


        

Answer 1

Because all attempts to print the argument I placed in my variable failed, here my 2 bytes for this question:

std::string dump_name;

(stuff..)

if(argc>2)
{
    dump_name.assign(argv[2]);
    fprintf(stdout, "ARGUMENT %s", dump_name.c_str());
}

Note the use of assign, and also the need for the c_str() function call.

Answer 2

It's already an array of C-style strings:

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


int main(int argc, char *argv[]) // Don't forget first integral argument 'argc'
{
  std::string current_exec_name = argv[0]; // Name of the current exec program
  std::vector<std::string> all_args;

  if (argc > 1) {
    all_args.assign(argv + 1, argv + argc);
  }
}

Argument argc is count of arguments plus the current exec file.

Answer 3

#include <iostream>

std::string commandLineStr= "";
for (int i=1;i<argc;i++) commandLineStr.append(std::string(argv[i]).append(" "));

Answer 4

No need to upvote this. It would have been cool if Benjamin Lindley made his one-liner comment an answer, but since he hasn't, here goes:

std::vector<std::string> argList(argv, argv + argc);

If you don't want to include argv[0] so you don't need to deal with the executable's location, just increment the pointer by one:

std::vector<std::string> argList(argv + 1, argv + argc);

Answer 5

It's simple. Just do this:

#include <iostream>
#include <vector>
#include <string.h>

int main(int argc, char *argv[])
{
    std::vector<std::string> argList;
    for(int i=0;i<argc;i++)
        argList.push_back(argv[i]);
    //now you can access argList[n]
}

@Benjamin Lindley You are right. This is not a good solution. Please read the one answered by juanchopanza.

Answer 6

You can create an std::string

#include <string>
#include <vector>
int main(int argc, char *argv[])
{
  // check if there is more than one argument and use the second one
  //  (the first argument is the executable)
  if (argc > 1)
  {
    std::string arg1(argv[1]);
    // do stuff with arg1
  }

  // Or, copy all arguments into a container of strings
  std::vector<std::string> allArgs(argv, argv + argc);
}