Characters, words and lines counting

Hi all, newbie here. I was trying to write a program that counts characters, words and lines from a text file. I wrote a function for every task, and because i'm pretty sure the problem is there i will post only that... if you need the whole program please tell me.

Characters:

Code:

---

int contaCaratteri(FILE* file){
        char buffer;
        int caratteri = 0;
       
        while (!feof(file)){
                fscanf(file, "%c",&buffer);
                if(buffer != ' ' || buffer != '\b' || buffer != '\n'){
                        caratteri++;
                }
        }
        return caratteri;
}

---

I don't want to include spaces, newline and EOF in the count...

lines:

Code:

---

int contaRighe(FILE* file){
        int righe = 1;
        char buffer;
       
        while (!feof(file)){
                fscanf(file, "%c",&buffer);
                if(buffer == '\b' || buffer == '\n'){
                        righe++;
                }
        }
        return righe;
}

---

I thought that every newline means a line more, and the first is sure :D

words:

Code:

---

int contaParole(FILE* file){
        int parole = 1;
        char buffer;
       
        while (!feof(file)){
                fscanf(file, "%c",&buffer);
                if(buffer == ' ' || buffer == '\b' || buffer == '\n'){
                        parole++;
                }
        }
        return parole;
}

---

same here: every space or newline, means a word, and the first is sure...

To speak the truth, i'm really not sure of the if conditions, i think the problem is there...

now, that is the answer of the program.. eg.

bla
bla
bla

13 characters (instead of 9)
1 line (instead of 3)
1 word (instead of 3)

thank you so much for your help!

Checkout ctype.h. It might make a few things easier for you.

Generally, you wouldn't make separate functions for these since they can all be done at the same time with one pass through the file.

You are not properly testing for end-of-file. You need to check the return value of fscanf.

Code:

---

while (fscanf(file, "%c", &buffer) > 0) {
    if (...)
        ...
}

---

But, now that I think about it, why are you using fscanf when fgetc would do?

Code:

---

int c;
while ((c = fgetc(file)) != EOF) {
    if (...)
        ...
}

---

Try implementing these ideas and then post your entire program.

In reality you should not be reading one byte at a time from disk. Yes your computer is most likely configured to batch up multiple reads to the same disk sector into one buffered read (thank goodness, if it didn't do that then your code would be thousands of times slower). However that still occurs a lot further down into what the runtimes, OS, disk drivers or even the drive itself does, with regards to preventing multiple reads, and so it's still much slower.

Just keep in mind that a real program would typically read in at least 4K, (4096 bytes) at once and then just iterate over all those bytes in memory, assuming the file size is more than a few Kb that is.

Quote:

---

Originally Posted by failure67

Checkout ctype.h. It might make a few things easier for you.

---

Yeah you are probably right... thing is, the excercise asked me to do that only stdio.h\stdlib.h\string.h (that function is not the whole excercise...)

Quote:

---

Originally Posted by oogabooga

Generally, you wouldn't make separate functions for these since they can all be done at the same time with one pass through the file.

You are not properly testing for end-of-file. You need to check the return value of fscanf.

Code:

---

while (fscanf(file, "%c", &buffer) > 0) {
    if (...)
        ...
}

---

But, now that I think about it, why are you using fscanf when fgetc would do?

Code:

---

int c;
while ((c = fgetc(file)) != EOF) {
    if (...)
        ...
}

---

Try implementing these ideas and then post your entire program.

---

My tutor wants me to read and write on file only with fscanf and fprintf... or fread and fwrite for binary files... for now.
So I used the fscanf to test the end-of-file, but I don't understand what is wrong in the feof...

Code:

---

void counter(FILE* file, int* contatore){
        char buffer;
        int caratteri,righe,parole;
        caratteri = righe = parole = 0;
       
        while(fscanf(file,"%c",&buffer)>0){
                if(buffer != ' ' && buffer != '\b' && buffer != '\n'){
                        caratteri++;
                }else if(buffer == '\b' || buffer == '\n'){
                        righe++;
                        parole++;
                }else if(buffer == ' '){
                        parole++;
                }
        }
       
        *contatore = caratteri;
        contatore++;
        *contatore = righe;
        contatore++;
        *contatore = parole;
}

---

Additionally, there was an error in the first if condition: I used && instead of ||...

Now the program works perfectly. Thank you so much.

Quote:

---

Originally Posted by iMalc

In reality you should not be reading one byte at a time from disk. Yes your computer is most likely configured to batch up multiple reads to the same disk sector into one buffered read (thank goodness, if it didn't do that then your code would be thousands of times slower). However that still occurs a lot further down into what the runtimes, OS, disk drivers or even the drive itself does, with regards to preventing multiple reads, and so it's still much slower.

Just keep in mind that a real program would typically read in at least 4K, (4096 bytes) at once and then just iterate over all those bytes in memory, assuming the file size is more than a few Kb that is.

---

Thank you for the advice, it will be very useful in the future.