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POWhats the wrong with my C encryption program?
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copied!<p>So I'm trying to making a file encrypting program in C (by the way I'm kind of new to C) so I wrote this simple XOR file encryption code:</p> <pre><code>#include <stdio.h> #include <string.h> int main() { char fileName1[35] = {'\0'}; //Name of original file char fileName2[35] = {'\0'}; //Name of encrypted file char keyString[20] = {'\0'}; //Key determines result encryption FILE* originalFile; //File to be encrypted FILE* cryptedFile; //The encrypted file int c; //byte read from original file printf("Enter file location followed by name of the file you want to encrypt: "); scanf("%s", fileName1); printf("Enter file location followed by name of the encrypted file: "); scanf("%s", fileName2); printf("Enter your key (Encryption changes based on Key): "); scanf("%s", keyString); originalFile = fopen(fileName1, "rb"); //rb to read file bytes cryptedFile = fopen(fileName2, "wb"); //wb to write bytes to file if(originalFile != NULL && cryptedFile != NULL){ while( (c = getc(originalFile)) != EOF ){ int x; for(x=0; x<strlen(keyString); x++){ c ^= keyString[x]; putc(c, cryptedFile); } } fclose(originalFile); fclose(cryptedFile); } return 0; } </code></pre> <p>So to test this program I created a file called file1.txt and run the encryption program giving it the second file as file2.txt and key as <em>secret</em>. Then I ran the program again but this time on the encrypted file2.txt and created a file3.txt with the same key <em>secret</em>. Since it was the same key the file3.txt should be the same as file1.txt but file3.txt has random contents in it. So what am I doing wrong?</p>

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