Passing in arguments in C

Question

How could I do something like this? I'm making a Sockets program that connects one program with another program via a port number. I want to pass in a command of -p that stands for port and then have a number after it to designate the port number. Example: -p 9013 for Port 9013.

Here is what I have so far:

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

    for (i = 1; i < (argc - 1); i++) {
        if (strcmp("-p", argv[i]) == 0) {
            // add whatever comes after -p and declare portNumber as that integer
        }
    }
}

Any clue how I can maybe start this?

Did a search come up with nothing? I would think you are not the first person to want to use command line args. — kaylum, Oct 04 '16 at 02:22
http://pubs.opengroup.org/onlinepubs/009695399/functions/getopt.html — Amadan, Oct 04 '16 at 02:25
Well, basically, how can I take those four or whatever numbers after -p and set those numbers as portNumber (integer)? — Burnie, Oct 04 '16 at 02:27

score 1 · Accepted Answer · answered Oct 04 '16 at 02:30

1

if (strcmp("-p", argv[i]) == 0) {
    portNumber = atoi(argv[i+1]) // Might want to check argv[i+1] exists in case the last command line parameter is "-p"
}

answered Oct 04 '16 at 02:30

galfisher

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Passing in arguments in C

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