How to specify End of file (EOF) in C online compiler like in jdoodle?

Question

This is a program for copying content from one file to other file. How to specify EOF in online compiler so that my code will run as expected??

Link for online editor---> https://www.jdoodle.com/c-online-compiler

//code for copying content--->>

#include "stdio.h"

int main()
{
char ch;
FILE *p,*q;
p=fopen("data.txt","w");
while(ch=getchar()!=EOF)
{
    putc(ch,p);
}

fclose(p);
p=fopen("data.txt","r");
q=fopen("newdata.txt","w");
while(ch=getc(p)!=EOF)
{
    putc(ch,q);
}

fclose(p);
fclose(q);
q=fopen("newdata.txt","r");
while(ch=getc(q)!=EOF)
{
    printf("\n%c",ch);
}

}

score 2 · Answer 1 · answered Oct 22 '17 at 07:45

2

There are two problems with the expression ch=getchar()!=EOF:

The first is that getchar returns an int. This is actually important for the EOF comparison.
The second problem is about operator precedence. You expression is really ch = (getchar() != EOF). That is, you assign the result of the comparison (which is an 1 or 0) to the variable ch.

To solve the first problem, define the variable ch as an int.

To solve the second problem use explicit parentheses: (ch = getchar()) != EOF.

answered Oct 22 '17 at 07:45

Some programmer dude

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Your 2nd point is correct. But in the Ist point getchar() is a function which is used for reading inputs from keyboard. It reads single character at a time. – rohitgoelrg Oct 22 '17 at 07:50
2

@rohitgoelrg [please read and understand](https://stackoverflow.com/questions/35356322/difference-between-int-and-char-in-getchar-fgetc-and-putchar-fputc) – Antti Haapala -- Слава Україні Oct 22 '17 at 08:12

How to specify End of file (EOF) in C online compiler like in jdoodle?

1 Answers1