Command line arguments

• Command-line arguments 
  • arguments that are passed to your program at the command line
  • Ex) all statements you typed after clang are considered command line arguments → You can use these arguments in your own programs!

Example

// Prints a command-line argument
#include <cs50.h>
#include <stdio.h>
 
int main(int argc, string argv[])
{
	if (argc == 2)
	{
		printf("hello, %s\n", argv[1]);
	}
	else
	{
		printf("hello, world\n");
	}
}

• int argc, string argv[]

  • argc: The number of command line arguments
    • stands for argument count
  • argv: An array of the characters passed as arguments at the command line
    • stands for argument vector (often another word for array)

• You can print each of the command-line arguments with the following:

// Prints command-line arguments
 
#include <cs50.h>
#include <stdio.h>
 
int main(int argc, string argv[])
{
	for (int i = 0; i < argc; i++)
	{
		printf("%s\n", argv[i]);
	}
}