C++ Primer Plus

Command-Line Processing

File-processing programs often use command-line arguments to identify files. Command-line arguments are arguments that appear on the command line when you type a command. For example, to count the number of words in some files on a Unix or Linux system, you would type this command at the command-line prompt:

wc report1 report2 report3

Here wc is the program name, and report1, report2, and report3 are filenames passed to the program as command-line arguments.

C++ has a mechanism for letting a program running in a command-line environment access the command-line arguments. You can use the following alternative function heading for main():

int main(int argc, char *argv[])

The argc argument represents the number of arguments ...