obout FILE PROCESSING???

my program is running, but logically wrong..

Assume that there are two text files. write a program that will determine whether these two text files are identical or not..

it doesn't important if the program print the content of each program.. the important is it compare the content of the first text file to another text file... and print only whether they're equal or not

help me please and give me some advice....

heres my program..

Code:

---

#include<stdio.h>
void main(void)
{
FILE *inputf1;
FILE *inputf2;
int x,y;
char filename1[40];
char filename2[40];


printf("Input name of the text file:\n");
scanf("%s",&filename1);
printf("Input another text filename:\n");
scanf("%s",&filename2);
if(filename1!=filename2)
printf("they're not equal\n");

if((inputf1 = fopen(filename1, "r")) == NULL)
if((inputf2 = fopen(filename2, "r")) == NULL)
{
printf("ERROR: %s cannot be opened:\n",filename1);
printf("ERROR: %s cannot be opened too:\n",filename2);
getch();
exit(1);
}
while((x = fgetc(inputf1)) !=EOF)
while((y = fgetc(inputf2)) !=EOF)
printf("%c",x);
printf("%c",y);

fclose(inputf1);
fclose(inputf2);
}

---

so many Thanks for all of your help...

Perhaps you can see your error now that I have taken the time to properly indent your code (well, as best it can be, I guess, without altering any logic).

Code:

---

#include<stdio.h>
void main(void)
{
        FILE *inputf1;
        FILE *inputf2;
        int x,y;
        char filename1[40];
        char filename2[40];

        printf("Input name of the text file:\n");
        scanf("&#37;s",&filename1);
        printf("Input another text filename:\n");
        scanf("%s",&filename2);
        if(filename1!=filename2) printf("they're not equal\n");

        if((inputf1 = fopen(filename1, "r")) == NULL) if((inputf2 = fopen(filename2, "r")) == NULL)
                {
                        printf("ERROR: %s cannot be opened:\n",filename1);
                        printf("ERROR: %s cannot be opened too:\n",filename2);
                        getch();
                        exit(1);
                }
        while((x = fgetc(inputf1)) !=EOF) while((y = fgetc(inputf2)) !=EOF) printf("%c",x);
        printf("%c",y);

        fclose(inputf1);
        fclose(inputf2);
}

---

so whats the changes??? i do'nt see any changes their sir... anyway thanks...

Quote:

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Originally Posted by lesrhac03

so whats the changes??? i do'nt see any changes their sir... anyway thanks...

---

Since he explicitly stated that he did not change anything, I don't expect you to see any changes. However, you should see a line or three that look so incredibly amazingly wrong that you can't miss them. And since those lines are the same as your code, those are errors in your code as well.

sorry sir.. it was so hard for me to understand it.. the alignment of the codes and what code to be use in order to accomplish the given requirements...

Code:

---

#include<stdio.h>
void main(void) /* should be int main(void) - read FAQ */
{
        FILE *inputf1;
        FILE *inputf2;
        int x,y;
        char filename1[40];
        char filename2[40];

        printf("Input name of the text file:\n");
        scanf("&#37;s",&filename1); /* drop the & */
        printf("Input another text filename:\n");
        scanf("%s",&filename2);/* drop the & */
        if(filename1!=filename2) printf("they're not equal\n"); /* use strcmp to compare strings*/

        if((inputf1 = fopen(filename1, "r")) == NULL)
                if((inputf2 = fopen(filename2, "r")) == NULL)
                {
                        printf("ERROR: %s cannot be opened:\n",filename1);
                        printf("ERROR: %s cannot be opened too:\n",filename2);
                        getch();
                        exit(1);
                }
/* why do you need 2 handles if you want filenames to be equal? */
/* what if only one file failed to open? */
        while((x = fgetc(inputf1)) !=EOF)
                while((y = fgetc(inputf2)) !=EOF)
                        printf("%c",x); /* so you write the first char from the first file number of times
equal to number of chars in the second file
each other char you do not print at all

what's the point?
*/
        printf("%c",y);/* y is EOF - what is the point? */

        fclose(inputf1);
        fclose(inputf2);
        /* return 0; - would be proper ending */
}

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Quote:

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if(filename1!=filename2) printf("they're not equal\n");

---

This compares the filenames (wrongly, use strcomp) and not the contents of the files.

QuantumPete

Reading strings with scanf is prone to buffer overruns. See:
http://cboard.cprogramming.com/showp...37&postcount=9

Code:

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if((inputf1 = fopen(filename1, "r")) == NULL)
                if((inputf2 = fopen(filename2, "r")) == NULL)

---

Er? So you only open the second file if the first failed?

Banish yourself to the design board, this could be done with a flow chart in a few minutes. Seriously, It's like comparing strings, except you're comparing the contents of files. Compare the bytes (characters if you will), while they match AND you're not at the end of either file then the file's are identical.

ie,

Code:

---

1 Open file A
2 Open file B
3 Read a byte from file A
4 Read a byte from file B
5 Compare the byte from A with the byte from B, if they match loop from step 3.
6 Close A
7 Close B

---

You should be able to fill in the missing steps, checking for EOF and whatever.