Counting the number of lines in a text file - help

Hi all,

I wanted to write a program which will count the number of lines in a text file. And I tried to modify a example to do this. This is what I have written:

Code:

---


/* This program counts the lines in a text file */

#include <stdio.h>

#include <stdlib.h>

int main(int argc, char *argv[])

{
int ch;

FILE *fp;

long NumberOfLines = 0;


if (argc != 2)

{
printf ("Usage: %s filename\n", argv[0]);

exit(1);

}

if ((fp = fopen(argv[1], "r")) == NULL)

{
printf("Can`t open %s\n", argv[1]);

exit(1);

}

while ((ch = getc(fp)) != EOF)

{
if (ch = "\n") NumberOfLines++;
}

fclose(fp);

printf("File %s has %ld lines\n", argv[1], NumberOfLines);

return 0;


}

---

It doesn`t work. It counts the number of characters.

My question is how does the program understands when it comes to the end of the line? There`s EOF for end-of-file, is there sth similar for end-of-line?
Thanks in advance for your answers.

Have you tried 'fgetc', instead of 'getc'?

Using fgetc to control a while loop is not good practice - read the FAQ.

fgets() reads the file one line at a time, so just create a loop that counts the number of times fgets() returns something other than NULL pointer.

Code:

---

char line[1024];
NumberOfLines = 0;
while( fgets(line,sizeof(line),fp) != NULL)
  NumberOfLines++;

---

Code:

---

if (ch = "\n") NumberOfLines++;

---

Shouldn't this be:

Code:

---

if(ch == '\n')
  NumberOfLines++;

---

?

ahluka: I can't find what you're referring to in the FAQ's eerrrr.... couldn't give me a link could you :)?

> Using fgetc to control a while loop is not good practice - read the FAQ.
That's feof(), not fgetc.
There's nothing wrong with the loop as posted.

> if (ch = "\n") NumberOfLines++;
1. use == not =
2. use '\n' for a char, "\n" is a 1-character string.

Everybody,
Thank you very much for your quick response. It was a great help for a novice like me.

Check This

http://www.cprogramming.com/challenges/countsol.html

I worked through the line counting challenge problem.

I almost have it but I am not clear on how I am to code for reading the file.
I keep getting the

cout<<"Input should be of the form 'count filename.txt'";

So I am not sure how to modify the code to read my file

file is named ten.txt (it has ten rows of characters.

any advice?

thanks
CS

Quote:

---

Have you tried 'fgetc', instead of 'getc'?

---

They do the same thing, except getc is a macro, so don't use it for code that has side effects, like this:

Code:

---

getc(*s++);

---

cout is C++. What do you mean, you keep getting it?

[edit]Here's the feof() link: http://faq.cprogramming.com/cgi-bin/...&id=1043284351[/edit]

You mean you want to change

Code:

---

if ((fp = fopen(argv[1], "r")) == NULL)

---

into

Code:

---

if ((fp = fopen("ten.txt", "r")) == NULL)

---

Oh, I know what you mean by the cout now. It's in that other link. You need to run that sample program like this:

Code:

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C:\DWK>count ten.txt

---