Multi-character character constant warning

Hi,
I'm trying to learn C and I'm using K&R second edition. I am copying this example in the book called 'Line counting'. The code is

Code:

---

#include <stdio.h>

main()
{
        int c, nl;
        nl = 0;
        while((c=getchar()) != EOF){
                if (c == '/n')
                        ++nl;}
        printf("%d\n",nl);
}

---

When I compile it, I get an error.

Code:

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visuthan@visuthan:~/Projects/C$ gcc line_counter.c -o line_counter
line_counter.c: In function ‘main’:
line_counter.c:8:12: warning: multi-character character constant [-Wmultichar]

---

Can someone explain what this means? I tried reading online but I really can't figure out the replies in most posts.

Also, can anyone tell me how I can create an EOF situation when getchar() is listening?

Compare your "newline" character in this piece of code:

Code:

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if (c == '/n')

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... to the "newline" character in this piece of code:

Code:

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printf("%d\n",nl);

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The former is written incorrectly, the latter correctly. Carefully note the direction of the slashes.

Quote:

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Originally Posted by visuthan

When I compile it, I get an error.

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'/n' should be '\n'

Quote:

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Originally Posted by visuthan

Can someone explain what this means?

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By using the wrong slash, you wrote a single character constant comprised of the characters '/' and 'n'.

Quote:

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Originally Posted by visuthan

Also, can anyone tell me how I can create an EOF situation when getchar() is listening?

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You probably can trigger EOF by entering CTRL + D or CTRL + Z.

Matticus and laserlight. Thanks a lot. I'm so dumb.

And just so it might help someone else. I have confirmed that CTRL + D creates an EOF whereas CTRL + Z tends to stop the program (process state T).