1. Announcements and Reminders Recitation sessions are being held this week, with focus on introducing students to Unix systems You’re responsible for policies listed in the course syllabus Class moodle page is now available – can access department moodle site from link in Sweany’s web page

2. Chapter 1 What is system programming ? Why Unix ? (section 1.1.2) Why C ? (section 1.1.3) Three “primary” tools (section 1.2) Shell Text editor Debugger

3. Software Process – Procedural Design Course Outcome 6. says “Using a software process model, design and implement a significant software application in C.” Waterfall process model (see Wikipedia) Procedural design – aka Hierarchical Design Top-Down Design Stepwise Refinement

4. Design Example – part 1 Design and implement a student database Create student database Add student data Delete student data Search for student records Print student record(s) Generate “statistics”

5. Design Example – part 2 Design and implement a “student database” Generate “statistics” – e.g. list all first-year students with gpa > 3.14 Parse inquiry Find data Perform Set operation(s) Print inquiry result

6. Design Example – part 3 Design and implement a “student database” Generate “statistics” – e.g. list all first-year students with gpa > 3.14 Parse inquiry Read command Extract set operation from string Extract set operands from string Put inquiry in canonical (standard) form Return canonical form of inquiry

7. Abstract Data Type (ADT) Course outcome 3. says “Describe the concept of an abstract data type (ADT)” ADT “describes” a new type of data Includes only two things – a name, and a list of operations E.G. --- Matrix ADT might include operations Create a matrix Add two matrices giving a new matrix to represent the sum Multiply two matrices giving a new matrix to represent the product Invert a matrix Find the determinant of a matrix Print a matrix Notice that NO implementation details included in ADT

8. Set ADT Name – Set Operations Create a set Print a set Add element to a set Remove element from a set Compute intersection of two sets Compute union of two sets

9. Your Turn Provide an ADT for a “list” Provide an ADT for “student database” – or have we already done this?