c- segmentation fault error due to calling a function that has text that user put in the terminal

Question

Summary

I am trying to pass the text that user has put in the terminal and pass it to the function named printString(). I don't fully understand C but I think I has to do with the pointer not being in the heap. Any help would be appreacitaed!

#include <stdio.h>
void printString();
int main (int argc, char* argv[]) {
        int commandAmount = 1;
        while (commandAmount < argc) {
        printString(commandAmount, &argv);
        }
        return 0;
}
void printString(int commandAmount, char* argv[]) {
        printf("the word is %s," , argv[commandAmount]);
}

./shortExample example

Segmentation fault (core dumped) 

Answer 1

The prototype void printString(); does not match the actual implementation. It should have been:

void printString(int commandAmount, char* argv[]);

You could also skip the prototype and just implement the function before main. Your loop while (commandAmount < argc) seems to not have any way to finish since you never increase commandAmount. This can cause undefined behavior and with such, your program may crash or do just about anything. I suggest making a for-loop to fix that.

Example:

#include <stdio.h>

void printString(int commandAmount, char* argv[]) {
    printf("the word is %s,", argv[commandAmount]);
}

int main(int argc, char* argv[]) {
    for(int commandAmount = 1; commandAmount < argc; ++commandAmount) {
        printString(commandAmount, argv);
    }
}

or in the way you structured it:

#include <stdio.h>

void printString(int commandAmount, char* argv[]); // corrected

int main(int argc, char* argv[]) {
    int commandAmount = 1;
    while (commandAmount < argc) {
        printString(commandAmount, argv);
        ++commandAmount;                           // needed
    }
}

void printString(int commandAmount, char* argv[]) {
    printf("the word is %s,", argv[commandAmount]);
}