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--- user:skinney1:portfolio:cprogproject1 [2012/02/26 02:20] – [Code] skinney1
+++ user:skinney1:portfolio:cprogproject1 [2012/03/12 17:44] (current) – [Scope] wedge
@@ Line 1: / Line 1: @@
+======Project: SECRET AGENT======
+A project for COURSENAME by YOUR NAME during the SEMESTER YEAR.
+This project was begun on DATE and is anticipated to take TIME UNIT to complete. Project was completed on MONTH DAY, YEAR.
+=====Objectives=====
+Create a program that will encrypt and de-crypt a file as needed.
+=====Prerequisites=====
+In order to successfully accomplish/perform this project, the listed resources/experiences need to be consulted/achieved:
+  * successful completion of project #0 and solid understanding of pertinent topics
+  * familiarity with memory allocation via **malloc(3)**
+  * familiarity with looking up C function parameters/information in the manual
+  * familiarity with if statements, especially in use for error detection
+  * familiarity with pointers and pointer arithmetic
+  * familiarity with loops
+  * file I/O
+=====Background=====
+State the idea or purpose of the project. What are you attempting to pursue?
+Upon approval, you'll want to fill this section out with more detailed background information. DO NOT JUST PROVIDE A LINK.
+Providing any links to original source material, such as from a project page, is a good idea.
+You'll want to give a general overview of what is going to be accomplished (for example, if your project is about installing a web server, do a little write-up on web servers. What is it, why do we need one, how does it work, etc.)
+=====Scope=====
+This project will test your familiarity with more involved algorithms, storage, and control structures.
+Encoding is the process of converting a message into a coded form.
+Decoding is the reverse- retrieving that original message from an encoded form.
+In this project you will write a 2 programs: one that will take a plain text message and convert it into a coded form (largely indecipherable to the regular english expecting eye) using a given cipher key, and another that will reverse the process (or decipher), when given the appropriate key.
+The key is a numeric used to rotate the alphabet a set amount. Where A would normally equal 1, and Z 26, using a cipher key of 1 to shift 1 position to the right; A would now equal 2 (or B), B is now 3 (or C), and Z would be 1 (A).
+Your encoding program can operate as follows:
+  * obtains its cipher key from a text file called "key.txt"
+  * or, if you prefer, use command-line arguments to provide the key
+  * obtains the input message from a file called "message.txt"
+  * if "plain.txt" is blank, or does not exist, the program should prompt the user to enter the message via STDIN
+  * outputs the ciphertext message to STDOUT **AND** saves it to a file called "cipher.txt"
+  * implement error checking to avoid segfaults
+The decoding operation is essentially the reverse (shifting to the left). I'd suspect you could reuse much of the same logic.
+Your decoding program:
+  * obtains its cipher key from a text file called "key.txt"
+  * or, if you prefer, use command-line arguments to provide the key
+  * obtains the input cipher from a file called "cipher.txt"
+  * if "cipher.txt" is blank, or does not exist, the program should prompt the user to enter the message via STDIN
+  * outputs the plaintext message to STDOUT **AND** saves it to a file called "plain.txt"
+  * implement error checking to avoid segfaults
+If you want, you may implement both functionalities into one program so long as you provide a mechanism for the user to access both operations (but note this is not required for successful completion of this project).
+<code c>
+#include <stdio.h>
+#include <stdlib.h>
+int main()
+{
+        FILE *in;
+        char *c, fname[] = "message.in";
+        int i;
+        int *input[255];
+        printf("Do you want to encrypt the file: ");
+        scanf("%d", input);
+        if (*input == 'y' || *input == 'Y')
+                {
+                        c = fgetc(in);
+                        while(c != EOF)
+                        {
+                        if((c >=65) && (c <= 'Z'))
+                                c++;
+                        else if((c >= 'a') && (c <= 'z'))
+                                c++;
+                        if((c == ('Z' + 1)) || (c == ('z' + 1)))
+                                c = c - 26;
+                        fprintf(stdout, "%c", c);
+                        c = fgetc(in);
+                        }
+                }
+                else if (*input == 'n' || *input == 'N')
+                {
+                        c = fgetc(in);
+                        while(c != EOF)
+			{
+                        if((c >=65) && (c <= 'Z'))
+                                c--;
+                        else if((c >= 'a') && (c <= 'z'))
+                                c--;
+                        if((c == ('Z' + 1)) || (c == ('z' + 1)))
+                                c = c - 26;
+                        fprintf(stdout, "%c", c);
+                        c = fgetc(in);
+                        }
+                }
+                fclose(in);
+                return (0);
+}
+</code>
+error from code, unable to get this to execute
+<cli>
+Do you want to encrypt the file: Y
+Segmentation fault
+lab46:~/src/cprog/classproject$
+</cli>
+=====Reflection=====
+Comments/thoughts generated through performing the project, observations made, analysis rendered, conclusions wrought. What did you learn from doing this project?
+=====References=====
+In performing this project, the following resources were referenced:
+  * URL1
+  * URL2
+  * URL3 (provides useful information on topic)
+  * URL4
+Generally, state where you got informative and useful information to help you accomplish this project when you originally worked on it (from Google, other wiki documents on the Lab46 wiki, etc.)

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