Thread: Real problems reading from a text file into an array

Originally Posted by man fgetc

NAME
fgetc, fgets, getc, getchar, gets, ungetc - input of characters and strings

SYNOPSIS
#include <stdio.h>

int fgetc(FILE *stream);

You are attempting to get a char from fgetc() which returns an int.

fgetc is made for char's as far as I'm aware? And I only use fgetc in the dictAtrb function, which is not where I am having my issues. It quite happily reads through the file and counts the number of words and the longest word. It's when I try to use fgets to read the strings into my array in the buildDict function that I encounter issues.

Okay, well I've changed it to int c = 0; and it works exactly the same as before, with the same error. Still having issues with my buildDict function

The dictArray[] only has room for six char's. Wow! that's not much. You'll really have to watch out for array over-runs.

Code:

void buildDict()
{
	FILE *dictFile;
	char tempArray[BUFSIZ];
	char dictArray[6];
	char *p;
	int i = 0, count = 0, maxCount = 6;
	
	if((dictFile = fopen(dict,"r")) == NULL)
	{
		printf("Could not load dictionary");
		exit (1);
	}
	
	while(fgets(tempArray, BUFSIZ, dictFile) != NULL)
	{
		if((p = strchr(tempArray, '\n')) != NULL)
		{
			*p = '\0';
		}
		if(count == maxCount)
		{
			break;
		}
		strcpy(dictArray[count], tempArray);
		count++;
	}
	
	for(i; i < count; i++)
	{
		printf("%s\n", dictArray[i]);
	}
	
	fclose(dictFile);
}

Then, strcpy() is being given an array element as the destination, when strcpy needs a pointer to char. Maybe you meant:

strcpy(&dictArray[count], tempArray); //??

The size problem remains, however. You can't copy tempArray into dictArray[] - just not nearly enough room.

I recommend using strncpy() instead, and giving maxCount as the last parameter to it:

strncpy(dictArray, tempArray, maxCount);

Then, in the for loop that prints dictArray, you're mixing printing char by char, with printing by an entire string.

printf("\n %s", dictArray); should be all you need *IF* your strings have an '\0' char on the end of them to mark them as strings, and not just as a bunch of char's.

I haven't run your code yet, but will do so, if this doesn't help you resolve the problem.

I decided to try a different approach, and voila it seems to be working! To an extent...

Code:

void buildDict()
{
	FILE *dictFile;
	char dictArray[100];
	int c = 0;
	int i = 0, count = 0, maxCount = 6;
	
	if((dictFile = fopen(dict,"r")) == NULL)
	{
		printf("Could not load dictionary");
		exit (1);
	}
	
	while(c != EOF)
	{
		c = fgetc(dictFile);
		dictArray[i] = c;
		i++;
	}
	
	int length = strlen(dictArray);
	
	i = 0;
	
	for(i;i < length; i++)
	{
		printf("%c",dictArray[i]);
	}
	
	fclose(dictFile);
}

Only problem now is that for whatever reason it prints my dictionary successfully, but with a weird y and E at the end, with two dots above each word

Those last two char's are showing a fault to your logic. Somehow, someway, your program is not putting an end of string char to mark the end of the word, where it needs to go.

Myself, I am wondering why you're reading in an entire file, when you only are using one word. What's with that?

Trim down your input to what you need, get each word marked with an end of string char, and it will all come together for you.

I'm reading in every word because I then need to be able to use the list of words to choose a random word to be guessed. I'm not sure if I can randomly choose a word directly from the input file without loading them into an array first?

My latest attempt:

Code:

void buildDict()
{
	FILE *dictFile;
	char dictArray[100];
	int c = 0;
	int i = 0;
	
	if((dictFile = fopen(dict,"r")) == NULL)
	{
		printf("Could not load dictionary");
		exit (1);
	}
	
	while(c != EOF)
	{
		c = fgetc(dictFile);
		
		if(c == '\n')
		{
			dictArray[i] = '\0';
			i++;
		}
		else
		{
			dictArray[i] = c;
			i++;
		}
	}
	
	int length = strlen(dictArray);
	
	i = 0;
	
	for(i; i < length; i++)
	{
		printf("%c",dictArray[i]);
	}
	
	fclose(dictFile);
}

The problem now is that it won't print ANYTHING from the array.

Originally Posted by cherryduck

I'm reading in every word because I then need to be able to use the list of words to choose a random word to be guessed. I'm not sure if I can randomly choose a word directly from the input file without loading them into an array first?

Then why not use a 2D char array?

It's easy to stick some words into a 1D array, but it's a PITA to go ahead and work with them, from a 1D array:

Code:

words[] = {"I like riding"};

words[3][] {
{"I"},
{"like"},
{"riding"}};

Now it's so simple to work with the words in the 2D array.

Code:

for(i = 0; i < 3; i++)
  printf("\n %s ", words[i]);

Because every word is in it's own row (the first index of the 2D array. You can work with a char *pointer the same way, but ONLY (AFAIK), if the data is put into it, when it's declared, and that's not what you want.

This is the normal C array type for working with strings (An array of char pointers along with an array of char's, is the very best way to do this, but not needed for a small word list).