adds CSV documentation

src/csv.c

@@ -76,6 +76,7 @@ void write_to_file(book_t* book)
 	file_exists = access(FILE_NAME, F_OK);
 	if (0 != file_exists) {
 		file = fopen(FILE_NAME, "w");
+		// write the csv headers to the file since we're making it
 		fprintf(file, "id,isbn,title,authors,imageurl,year of publication,page length\n");
 		book_id = 1;
 	} else {

src/csv.h

@@ -3,10 +3,27 @@
 
 #define FILE_NAME "books.csv"
 
+/**
+ * int get_next_id
+ *
+ * Returns the next available ID so that we know what to assign to the book
+ */
 int get_next_id();
 
+/**
+ * void write_to_file
+ * boot_t* book - A pointer to the book information struct
+ *
+ * Writes the book information to a CSV file
+ */
 void write_to_file(book_t* book);
 
+/**
+ * long find_id
+ * int id_to_find - The ID we're looking for
+ *
+ * Returns the position of a FILE to the line with the ID we're looking for
+ */
 long find_id(int id_to_find);
 
 #endif