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cstrcmp

Why is strcmp not returning 0

In this mini version of my program I am asking for user input. When the input is 'quit' or 'exit' I want the program to exit the while loop. The strcmp function doesn't seem to be working as I expect. I've spent some time looking for answers but can't find the issue. Any ideas?

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define BUFFER_SIZE 100
int main() {
    char request[BUFFER_SIZE];
    while(strcmp(request, "quit") != 0 && strcmp(request, exit) != 0) {
        fgets(request, BUFFER_SIZE, stdin);
    }
    return 0;
}
Solution

  • fgets reads the trailing \n and stores it in the buffer, so you're always comparing quit to quit\n.

    Also at the first time the while loop examines its condition, very bad things could happen because your request array is not initialized.