Command-Line Arguments

• Passing Initial Information to Your Program

  • Up to now all the information our programs needed they acquired from keyboard input (usually after printing some prompt) or file input.

  • Information can also be passed from the command line.

  • This is common for many of the linux commands with which we are familiar

    • less filename (less is the program and filename is the name of the program we want to view)

    • cd directory (cd is the program and directory is the name of the location we want to change to)

  • Information passed from the command line (linux or DOS prompt) is called a "command-line argument"

• To pass information to your program, it needs to be passed to the first function invoked (that would be main()).

  • main() can take parameters just like any other function, only up to this point we've ignored that fact.

    • Ignored it, because one of those parameters is a pointer.

    • main()'s two command line parameters are an int and a char**.

    • Example:  command_line.cpp