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--- haas:fall2015:cprog:projects:sam0 [2015/10/27 17:57] – [Function prototype] wedge
+++ haas:fall2015:cprog:projects:sam0 [2015/10/29 12:26] (current) – [Sample execution: encode] wedge
@@ Line 26: / Line 26: @@
   * encoding - taking the readable text and making it obfuscated, according to a set process
   * decoding - taking the obfuscated text and making it readable, by reversing the process
-=====Task=====
+=====Program=====
 You are to implement two programs (or at least a program with two fundamental modes of operation):
   * encode program: takes plain text message as input, along with a cipher key, and outputs the encoded (obfuscated) result
@@ Line 37: / Line 37: @@
 You can implement this as two separate programs, or as one program that behaves fundamentally different depending on how it is named (ie **encode-sam0** operates in encode mode, **decode-sam0** operates in decode mode).
-Your program should accept input from **STDIN** until the **EOF** character is encountered.
+Your program(s) should:
+  * load the provided input (via STDIN) into an array for processing (you may want to check for an EOF character to terminate input)
+    * you may assume a maximum input size of 4096 bytes
+    * use the **fgetc()** function instead of **fscanf()** for reading input from STDIN
+  * obtain the signed char key value from the command-line, if present, or read from the 'cipher.key' file
+    * if neither command-line nor key file are available, display error and exit
+  * appropriately "shift" the alphabet according to the key (magnitude and direction and mode), storing the results in an array
+  * for encoding, display the resultant enciphered string to STDOUT
+  * for decoding, display the resultant deciphered string to STDOUT
 ====Sample execution: encode====
@@ Line 60: / Line 68: @@
 </cli>
+Without command-line nor cipher.key file:
+<cli>
+lab46:~/src/cprog/sam0$ ./encode-sam0
+ERROR: key not found
+lab46:~/src/cprog/sam0$
+</cli>
+With 4 in the cipher.key file:
+<cli>
+lab46:~/src/cprog/sam0$ ./encode-sam0
+hello there
+lipps xlivi
+^D
+lab46:~/src/cprog/sam0$
+</cli>
+With 4 in the cipher.key file, decoding previous message:
+<cli>
+lab46:~/src/cprog/sam0$ ./decode-sam0
+lipps xlivi
+hello there
+^D
+lab46:~/src/cprog/sam0$
+</cli>
+Via positive command-line key, decoding:
+<cli>
+lab46:~/src/cprog/sam0$ ./decode-sam0 2
+jgnnq
+hello
+^D
+lab46:~/src/cprog/sam0$
+</cli>
+You can also save typing, by providing your input via a here string (also a nice way to check for EOF):
+<cli>
+lab46:~/src/cprog/sam0$ ./decode-sam0 2 <<< "jgnnq"
+hello
+lab46:~/src/cprog/sam0$
+</cli>
 =====Submission=====
 To successfully complete this project, the following criteria must be met:

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