Read Command-Line Arguments

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Read the command line arguments, display the total number, and display each one, including any reference to the program itself. (i.e., if the language includes the name and path of the executable as one of the arguments, include it.)

C

#include<stdio.h>

int main(int argc, char *argv[])
{
	int narg;

	printf("There are %d arguments\n", argc);
	for(narg=0; narg<argc; ++narg) 
		printf("Argument #%d is %s.\n", narg, argv[narg]);

	return 0;
}

C++

#include <iostream>
int main( int argc, char *argv[] )
{
     std::cout << "There are " << argc << " arguments." << std::endl;
     for (int argnum = 0; argnum < argc; ++argnum)
     {
          std::cout << "Argument #" << argnum << " is " << argv[argnum] << "." << std::endl;
     }

     return 0;  
}

Haskell

import System.Environment

main = do
  prog <- getProgName
  args <- getArgs
  putStrLn $ "Program name: " ++ prog
  putStrLn $ "There are " ++ show (length args) ++ " arguments:"
  forM_ (zip args [1..]) $ \(a,i) -> 
    putStrLn $ "Argument #" ++ show i ++ " is " ++ a

Java

public class CmdLine{
  public static void main(String[] args){
     System.out.println("Number of args: " + args.length);
     for(int i= 0;i < args.length;i++) 
        System.out.println("Argument #" + (i+1) + ": " + args[i]);
  }
}

Perl

#!/usr/bin/perl

print "There are $#ARGV arguments.\n";
foreach $argnum ( 0 .. $#ARGV )
{
        print "Argument $argnum is $ARGV[$argnum].\n";
}