Thread: New programmer here!

Originally Posted by Phob0s

Hello all,

Does anyone know how to read a file, one character at the time, into an character array? No matter what I try I cant seem to get it to work.

Here is the basic code i have:

Code:

int count;
FILE *in;
    if (( in = fopen("tmp.tmp", "rb")) == NULL) 
   {
      printf("Error opening %s.n", "");
   }
   while(( count = getc(in)) != EOF) 
   {
      count = count ^ *key; 
   //store here
   }

}

Try these changes. You used a bad name (count)
for the input value, key_pressed would be better.





Code]
int count;
int realcount=0;
char key[100];
FILE *in;
if (( in = fopen("tmp.tmp", "rb")) == NULL)
{
printf("Error opening %s.n", "");
}
while(( count = getc(in)) != EOF)
{

key[realcounter++]=count;
if (realcounter>=99); break;


//store here
}
fclose(in);



Another possible change.


while ( fscanf("%c",&count)!=EOF)
while(( count = getc(in)) != EOF)

the number of characters are different for each execution...so we can't set number of elements in the array to a constant.

Not sure what you are saying.
Make the array[1000000] then and see how long it takes to fill it.
Do you know which key returns EOF?

basically i need to read one charater from a file, perform xor(^) on the character, then append the result to an existing array. I need to do this until the end of file. The only problem is that I don't know how to find the number of characters in the file, and thus do not know how many elements to give the array.

Sorry I though you were reading from a file, I find
getc confusing cos usually when you read from a
file you proceed the function call with an f, for
example scanf, fscanf.
Anyway just make the array large or you could
possiblly find the file size (somehow) and then use
something like malloc to allocate memory.
Alternatively you could write the data to another
file. The last option is probably best cos you don't
lose the data when the program finishes.

Originally Posted by tuxinator

This should alocate exactly enough memory for any file you try to open

Is there a way to read the file size directly so to speak,
I mean I think it is stored in the dirctory/folder info somewhere.
Also I would like to find the data of creation. Will start a thread on this.

Originally Posted by tuxinator

include statements (at least the ones I am using I am not sure which one does it).

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

Code Itself:

Code:

FILE *file = fopen("filename.txt", "rb")
if (file == NULL)
{
  perror("Error Opening File filename.txt");
}
fseek(file, 0, SEEK_END);
long size=ftell(file);
fseek(file, 0, SEEK_SET);
char* storage = malloc(char) * size+1;

This should alocate exactly enough memory for any file you try to open

Code:

char* storage = malloc((char)) * (size+1);

throws a syntax error: ')'

Originally Posted by Phob0s

Code:

char* storage = malloc((char)) * (size+1);

throws a syntax error: ')'

Try char* storage = malloc(char) * (size+1);
or char* storage = (malloc(char)) * (size+1);

Tried both...no cigar

OK


char * storage = malloc( sizeof(char) * (size+1) );

Not sure what you are trying to do.
Anyway I will have a Hamlet