CODEWITHSUNDEEP
c
user11006304
user11006304

Reputation: 137

How to compare argv and another string?

It's like my code doesn't compare the two. I don't understand why. It's the first if condition that gives me trouble. How can I do to solve the problem?

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

int main(int argc, char *argv[]){
    FILE *in;
    in = fopen(argv[1], "rw");
    char s1[30], s2[30], s3[30];

    if(strcmp(argv[2], "new") == 0){
        while(fscanf(in, "%s %s %s", s1,s2,s3) == 3){
            if(strcmp(s1, argv[3]) == 0 && strcmp(s2,argv[4])==0 && strcmp(s3, argv[5])==0){
                printf("Errore! Cartolina già esistente.\n");
                exit(0);
            }
        }
        fprintf(in, "%s %s %s\n", argv[3], argv[4], argv[5]);
    }

    if(strcmp(argv[2], "find") == 0){
        while(fgets(s1, 30, in) != NULL){
            if(strstr(s1, argv[3]) != NULL){
                printf("%s", s1);
            }
        }
    }

    return 0;


}

EDIT: I just realized that I used "r" instead of "rw" but it still doesn't print argv[3], argv[4] and argv[5] in the file.

Upvotes: 1

Views: 113

Answers (1)

dbush
dbush

Reputation: 223972

You're not opening the file correctly:

in = fopen(argv[1], "rw");

rw is not a valid mode. If you want to open for reading and writing, use r+ instead. Also, don't forget to check if fopen failed.

in = fopen(argv[1], "r+");
if (!in) {
    perror("fopen failed");
    exit(1);
 }

Upvotes: 1

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