Storing words from text file into char array using feof

Question

So I have a textfile which goes like this:

zero three two one five zero zero five seven .. etc

and there is a lot of it, 9054 words to be exact

My idea was to create a char array of 9054 spaces and store it in, this is what I have done so far:

#include <stdio.h>

int main(void)
{
char tmp;
int i = 0;
int j = 0;
char array[44000];

FILE *in_file;

in_file = fopen("in.txt", "r");

// Read file in to array
while (!feof(in_file))
{
      fscanf(in_file,"%c",&tmp);
      array[i] = tmp;
      i++;
}

// Display array
while (j<i)
{
      printf("%c",array[j]);
      j++;
}


fclose(in_file);

while(1);
return 0;
}

The problem is I don't know how to store words, because from what I have done stores each character into the array so it becomes an array of around 44000. How can I make it so the array holds words instead?

Also I don't have an idea what the feof function does, especially the line

while (!feof(in_file))

what does this line exactly mean? Sorry I am still in the baby stages of learning C, I tried looking up what feof does but there is not much to find

you are creating an array of chars but should create an array (or better: list) of strings. And for starters have a look at this for example: http://stackoverflow.com/questions/12337614/how-feof-works-in-c — Marged, Dec 02 '15 at 22:49
For your code you're saying, *...this is what I've done so far*, and then you are saying, *Also I don't have any idea what the feof function does...* and are using `feof`. If you wrote the code, why are you using `feof` if you don't know what it does? — lurker, Dec 04 '15 at 18:09

score 0 · Answer 1 · answered Dec 02 '15 at 22:50

Usually you may use the following steps:

Dump the whole text file to a char buffer.
Use strtok to split the char buffer to multiple tokens or words.
Use an array of pointer to char to store individual words.

Something along this line would do. Note, I use your question title as the text file. You will need to replace 20 as appropriately.

    int main ()
    {
        FILE *in_file;
        in_file = fopen("in.txt", "r");
        fseek( in_file, 0, SEEK_END );
        long fsize = ftell( in_file );
        fseek( in_file, 0, SEEK_SET );

        char *buf = malloc( fsize + 1 );
        fread( buf, fsize, 1, in_file ); // Dump the whole file to a char buffer.
        fclose( in_file );

        char *items[20] = { NULL };
        char *pch;

        pch = strtok (buf," \t\n");
        int i = 0;
        while (pch != NULL)
        {
            items[i++] = pch;
            pch = strtok (NULL, " \t\n");
        }

        for( i = 0; i < 20; i++ )
        {
            if( items[i] != NULL )
            {
                printf( "items[%d] = %s\n", i, items[i] );
            }
        }
        return 0;
    }

Output:

items[0] = Storing
items[1] = words
items[2] = from
items[3] = textfile
items[4] = into
items[5] = char
items[6] = array
items[7] = using
items[8] = feof?

score 0 · Accepted Answer · answered Dec 02 '15 at 22:51

0

Rather than check feof(), which tells you if the end-of-file occurred in the previous input operation, check the result of fscanf()
Reads "words" with "%s" and limit the max numbers of char to be read.
```
char buf[100];
fscanf(in_file,"%99s",buf);
```

Putting that together:

    #define WORD_SIZE_MAX 20
    #define WORD_COUNT_MAX 10000

    char array[WORD_COUNT_MAX][WORD_SIZE_MAX];
    unsigned word_i = 0;

    for (i=0; i<WORD_COUNT_MAX; i++) {
      if (fscanf(in_file,"%19s", word_list[i]) != 1) {
        break;
      }
    }

Another approach is to use OP code nearly as is. Read the whole file into 1 array. Then on printing, skip white-space.

answered Dec 02 '15 at 22:51

chux - Reinstate Monica

143,097
13
135
256

hello thanks for the reply, what do you mean by reads words with %s? – anony Dec 03 '15 at 17:42
and why am i creating an array with rows and columns(wordcountmax and wordsizemax)? please help! – anony Dec 03 '15 at 17:43
@anony Each `word_list[i]` stores 1 word with up to `WORD_SIZE_MAX-1` characters. The fixed sized `array[][]` supports up to `WORD_COUNT_MAX` words. Other approaches exist involving memory management (`malloc()/free()`. I thought this would be simplest for you to code and use. – chux - Reinstate Monica Dec 03 '15 at 18:11
i mean, the numbers in my textfile max' characters a word could have is 5. (seven, three, eight). so would the word_size_max be 5 for me? i tried using your code but it is too confusing for me :/ which file exactly in your code does the scanning words into array business? – anony Dec 03 '15 at 18:27
@anony The above comment "... with up to `WORD_SIZE_MAX-1` characters." implies that if the longest word is 5 characters, then `WORD_SIZE_MAX` needs to be _at least_ 6. In this answer `infile` is the `FILE` pointer, used just like in your post. The `fscanf()` performs the scanning. – chux - Reinstate Monica Dec 03 '15 at 18:48
http://textuploader.com/5gde8 this is my code.. i think i confused myself with it :/ – anony Dec 03 '15 at 19:14
after a lot of time looking at this, i think i've finally figured it out, thanks very much for the help! – anony Dec 04 '15 at 00:18
@anony Ref code should be `if (fscanf(in_file,"%5s", array[i]) != 1) {` 5 not 19 as you have `char array[45000][6];` and not `char array[45000][20];` – chux - Reinstate Monica Dec 04 '15 at 03:15

Storing words from text file into char array using feof

2 Answers2