Warning initialization makes integer from pointer without a cast with fgets

Question

I want want to read a character string, over the stdin, so I have chosen fgets. But I got this warning: initialization makes integer from pointer without a cast.

Here is my code:

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

#define MAX_LINIA 301

int main(int argc,char *argv[]){
    char *buffer;
    printf("Enter the input\n");
    if (fgets(buffer,MAX_LINIA-1,stdin)==NULL) printf("Error")
    else printf("%s", buffer);
    return 0:
}

The code should not emit the warning you cite above. Please show the real code you use — Ctx, Jan 11 '17 at 12:01
first, `printf("Error")` --> `printf("Error");` and `return 0:` --> `return 0;` — BLUEPIXY, Jan 11 '17 at 12:02
Using an uninitialised variable _in general_ is not undefined behaviour. But you dereference an indeterminate address. That's something different! — too honest for this site, Jan 11 '17 at 12:21

score 0 · Answer 1 · answered Jan 11 '17 at 11:59

0

You are using buffer without initialising it, which causes undefined behaviour.

You don't need to use pointer, and can use char array instead (given the max size already defined):

char buffer[MAX_LINIA];

The fgets then be better written as:

if(fgets(buffer,sizeof(buffer),stdin)==NULL)

answered Jan 11 '17 at 11:59

artm

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That's not exactly correct. Accessing the pointer is not UB in C, but dereferencing it's value is. – too honest for this site Jan 11 '17 at 12:23

Warning initialization makes integer from pointer without a cast with fgets

1 Answers1