Question

#include < stdio.h >

#include < string.h >

int main()

{

unsigned char a;

FILE *P;

P=fopen("mola.txt","r");

while((a=getc(P))!=EOF)

printf("%c",a);

}

Whats wrong with these code? When I compile it gives warning “comparison is always true due to limited range of data type.” What does that warning mean?

Answer 1

You are storing the result of getc in a char. It should be an int. There’s also a C FAQ on it. Also you should check the return value of the fopen.

P=fopen("mola.txt","r");
if (NULL == P) {
    perror("fopen"):
}

Also the while looks fishy. Try indenting ?

while((a=getc(P)) != EOF)
    printf("%c",a);