C Encryption?? Adding Encryption To Text File?

BillyBob's Avatar
Newbie Member
Hi I have this code to send a .txt file between 2 computers, I want to know how can I add simple encryption to it?
#include <stdio>
#include <conio>

#define CNTRLZ 0x1A

char sourceFileName[] = "H:\\text.txt";
char commStreamName[] = "COM1";
FILE *commStream;
FILE *SouceFile;
char charToSend;
char ReadAccess[] = "r";
char WriteAccess[] = "w";
char errorMsg[] = "fail to open data file\n";
char fileopenflag[] = "r";
char EndOfFile[] = "EOF";

int main(void) {
FILE *fp;
FILE *dp;
int c;

if ((dp = fopen("COM1", "r")) == NULL) {
printf("fail to open COM port\n"); return 1;

if ((fp = fopen( sourceFileName, "w")) == NULL) {
printf("fail to open data file\n"); return 1;

while ((c = fgetc(fp )) != EOF) {
fputc( c, dp);


fputc('*', dp);
I don't have a clue and please can someone give me an idea? also where where I stick the code, I'm still a noob.

Last edited by shabbir; 15Dec2007 at 12:16.. Reason: Code block
Salem's Avatar, Join Date: Nov 2007
Ambitious contributor
The poster doesn't want help to learn, he just wants a free lunch.
No point in even trying to help.

Last edited by Salem; 16Dec2007 at 19:48..
BillyBob's Avatar
Newbie Member
Bunch of fags, get off your computers and step outside for a minute.
pradeep's Avatar, Join Date: Apr 2005
Team Leader
If you want simple encryption, try this http://en.wikipedia.org/wiki/Caesar_cipher, it's really easy to implement!