COMS 4995 Advanced Systems Programming

Spring 2026

• COMS 4995-004: Mon & Wed 2:40-3:55pm, 633 Mudd 209 Havemeyer Hall

• Two synchronous and in-person exams:

  • Exam 1: Wednesday March 25, 2:40-3:55pm
  • Exam 2: Monday, May 4, 2:40-3:55pm
  • No final exam

  There are no make-up or alternate exams. If you cannot make any of those exams, please take the course next semester.

• Instructor: Jae Woo Lee

• Office hours:
  • Jae’s office hours
  • TA office hours

• REQUIRED READING: ACADEMIC HONESTY POLICIES

• Anonymous feedback form

• Attendance form

• 4157 Dev Guides

Important Dates

Date	What
F 1/23	HW0 due
R 2/12 Sa 2/14 (Hard deadline)	HW1 due
Su 3/1	HW2 due
Su 3/15	HW3 due
W 3/25	Exam 1
F 4/10	HW4 due

Course Schedule

Lecture 1: W 1/21

Course overview and logistics

• Lecture:
  • L00-overview

• Assignments:

  1. Subscribe to cs4157@lists.cs.columbia.edu – see L00 above

  2. Read the following two documents:
     • http://www.cs.columbia.edu/education/honesty
     • http://www.cs.columbia.edu/~jae/honesty.html

  3. HW0 (50 points, individual assignment) – due Fri 1/23, 11:59pm

     Send an email to Jae containing:

     • To: jae@cs.columbia.edu
     • Subject: “[4157] hw0-UNI” – without quotes, sole space before hw0, UNI replaced with your actual UNI in lowercase
     • Your name, major & school program, year – ex) Jae Woo Lee, Physics, Columbia College, class of 1994
     • Your pledge – see http://www.cs.columbia.edu/~jae/honesty.html
     • CS classes taken and/or other programming background
     • Optionally anything else you want to let us know
     • Optionally attach a picture of you, but please reduce image file size to about 100KB
  4. Start forming your group of up to three people

Git Overview and Internals

• Reading (optional)
  • Pro Git, entirely free online
    • Ch. 2: Git Basics
    • Ch. 3: Git Branching
    • Ch. 10: Git Internals
• Lecture:
  • L01-git-version-control

Lecture 2: M 1/26

Git Overview and Internals (continued)

• Lecture:
  • L01-git-version-control

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HW1: malloctopus

• 100 points, due Thu 2/12 Sat 2/14 (Hard deadline)
  • malloctopus

---

Lecture 3: W 1/28

Git Overview and Internals (continued)

• Lecture:
  • L01-git-version-control

GitHub

• Reading (optional)
  • Pro Git, entirely free online
    • Ch. 6: GitHub
• Lecture
  • L01-git-version-control

Lecture 4: M 2/2

Introduction to Memory Allocators

• Reading
  • CSAPP 9.1, 9.9 (skip 9.9.12)
• Lecture:
  • L02-memory-1

Lecture 5: W 2/4

Introduction to Memory Allocators (continued)

• Lecture:
  • L02-memory-1

Caching, Memory Mapping, and Advanced Allocators

• Reading
  • Caching: CSAPP 6.1 (optional), 6.2, 6.3, 6.4 (optional), 6.5, 6.6 (skim 6.6.1, read 6.6.2-3)
  • Memory mapping: APUE 14.8: read page 525-527 (skim the rest), 15.9: page 576-578
  • Allocators: CSAPP 9.9.13-14, APUE 7.8 “Alternative Memory Allocators”
• Lecture
  • L03-memory-2

Lecture 6: M 2/9

Caching, Memory Mapping, and Advanced Allocators (continued)

• Lecture
  • L03-memory-2
• Source code
  • Makefile
  • sum1.c, sum2.c
  • mult-ijk.c, mult-kji.c, mult-ikj.c

Lecture 7: W 2/11

Processes

• Reading
  • APUE 8.1-8.10 (8.4, 8.7, 8.8 optional)
• Lecture:
  • L04-process-control
• Source code
  • Makefile
  • shell1.c

Signals

• Reading:
  • APUE 9.4 - 9.6: skim, just to get a sense of process group, session, and controlling terminal
  • APUE 9.7: skim pages 299-301, skip rest – just to get a sense of jobs running in foreground and background
  • APUE 10.1 - 10.6 (skim signal descriptions in 10.2)
  • APUE 10.8 - 10.9
  • APUE 10.10: you can skip pages 340-341 & 343 (but interesting read if you know setjmp() / longjmp() or willing to find out)
  • APUE 10.11 - 10.13
  • APUE 10.14: skip page pages 352-353
• Lecture:
  • L05-signals
• Source code:
  • Makefile
  • shell2.c

---

HW2: greptile

• 100 points, due Sun 3/1
  • greptile

---

Lecture 8: M 2/16

Signals (continued)

• Lecture:
  • L05-signals
• Source code:
  • Makefile
  • read1.c

File I/O

• Reading:
  • APUE 3.1 - 3.13
  • APUE chapter 5 (skim)
• Lecture:
  • L06-file-io
• Source code:
  • Makefile
  • io.c
  • std-io.c

Lecture 9: W 2/18

File I/O (continued)

• Lecture:
  • L06-file-io
• Source code:
  • Makefile
  • fork-then-open.c
  • open-then-fork.c

POSIX threads

• Reading:
  • APUE 11.1 - 11.4
  • APUE 11.5: read page 388-393; skip the rest of 11.5
  • APUE 11.6: read up to (and including) 11.6.6
• Lecture:
  • L07-thread
• Source code:
  • Makefile
  • bank0.c
  • bank1.c

Lecture 10: M 2/23

POSIX threads (continued)

• Lecture:
  • L07-thread

Synchronization

• Reading:
  • CSAPP 12.5.2-4
  • APUE 15.10
• Lecture:
  • L08-synchro
• Source code:
  • Makefile
  • producer-consumer.c
  • producer-consumer.md

Lecture 11: W 2/25

Interprocess Communication in UNIX

• Reading:
  • Unnamed/named pipe: APUE 15.2, 15.5
  • Memory mapping (previously assigned): APUE 14.8: read page 525-527 (skim the rest), 15.9: page 576-578
  • Semaphore (previously assigned): CSAPP 12.5.2-4, APUE 15.10
• Lecture:
  • L09-ipc
• Source code:
  • Makefile
  • connect2.c
  • counter.c

---

HW3: cowchat

• 100 points, due Sun 3/15
  • cowchat

---

Lecture 12: M 3/2

Nonblocking I/O and I/O multiplexing

• Reading:
  • APUE 14.2
  • APUE 14.4.0 (i.e., page 500-501)
  • APUE 14.4.1
• Lecture:
  • L10-adv-io
• Source code:
  • Makefile
  • setfl.c
  • clrfl.c
  • nonblockw.c
  • logger.c

Lecture 13: W 3/4

Summary of UNIX IPC so far

• Lecture:
  • L11-dom-sock

UNIX domain sockets

• Reading:
  • APUE 17.1
  • APUE 17.2: pages 631-633 are optional, but recommended
  • APUE 17.2.1
  • APUE 17.3: pages 637-641 are optional, but recommended
  • APUE 17.4: read 642-643, skip the rest
• Lecture:
  • L11-dom-sock
• Source code:
  • Makefile
  • recv-unix.c
  • send-unix.c

Lecture 14: M 3/9

Threads 2

• Reading:
  • Thread safety & reentrancy: APUE 12.5, CSAPP 12.7.1-2
  • Threads & signals: APUE 12.8
  • Thread-specific data: skim APUE 12.6 just to get the idea
• Lecture:
  • L12-thread-2
• Source code:
  • Makefile
  • sig1.c
  • sig2.c
  • tls.c

Lecture 15: W 3/11

Threads 2 (continued)

• Lecture
  • L12-thread-2
• Source code:
  • Makefile
  • pthread.c
  • fork.c
  • mm-test.c

x86-64 Assembly

• Reading
  • CSAPP 3.0-3.1: Overview & History (optional)
  • CSAPP 3.2: Program Encodings (skim)
  • CSAPP 3.3: Data Formats
  • CSAPP 3.4: Accessing Information
  • CSAPP 3.5: Arithmetic & Logial Operation
    • 3.5.5 optional
  • CSAPP 3.6: Control
    • 3.6.6 and 3.6.8 optional
  • CSAPP 3.7: Procedures
  • CSAPP 3.8: Arrays
    • 3.8.3 is previously assigned
    • Skip 3.8.4-5
  • CSAPP 3.9: Heterogenous Data Structures
    • Everything except 3.9.1 is previously assigned
  • CSAPP 3.10: Combining Control and Data
    • 3.10.1, 3.10.3-4 optional
    • Skim 3.10.5
• Lecture
  • L13-x86-assembly

No Classes on M 3/16 & W 3/18 – Spring Break

Lecture 16: M 3/23

x86-64 Assembly (continued)

• Reading
  • CSAPP 3.0-3.1: Overview & History (optional)
  • CSAPP 3.2: Program Encodings (skim)
  • CSAPP 3.3: Data Formats
  • CSAPP 3.4: Accessing Information
  • CSAPP 3.5: Arithmetic & Logial Operation
    • 3.5.5 optional
  • CSAPP 3.6: Control
    • 3.6.6 and 3.6.8 optional
  • CSAPP 3.7: Procedures
  • CSAPP 3.8: Arrays
    • 3.8.3 is previously assigned
    • Skip 3.8.4-5
  • CSAPP 3.9: Heterogenous Data Structures
    • Everything except 3.9.1 is previously assigned
  • CSAPP 3.10: Combining Control and Data
    • 3.10.1, 3.10.3-4 optional
    • Skim 3.10.5
• Lecture
  • L13-x86-assembly
• Source code:
  • Makefile
  • main.c
  • sum.c

Exam 1: W 3/25

Exam 1

• Coverage
  • HW1, HW2, HW3
  • Lectures up to and including Lecture 15 on 3/11 (but not including x86 assembly)
  • All ANN emails
  • All assigned textbook readings

---

HW4: ladebug

• 100 points, due Fri 4/10
  • ladebug

---

Lecture 17: M 3/30

x86-64 Assembly (continued)

• Lecture
  • L13-x86-assembly
• Source code:
  • Makefile
  • main.c
  • sum.c

Interrupts

• Reading
  • CSAPP 8.1, 8.2.4, 8.2.5
• Lecture
  • L14-interrupts

Lecture 18: W 4/1

Interrupts (continued)

• Reading
  • CSAPP 8.1, 8.2.4, 8.2.5
• Lecture
  • L14-interrupts

HW4 ladebug Skeleton Code Overview & Demo

Lecture 19: M 4/6

HW4 ladebug Skeleton Code Overview & Demo (continued)

Introduction to ELF

• Reading
  • CSAPP 7.1 - 7.5, 7.8 - 7.9
• Lecture
  • L15-elf-intro

Linking

• Reading
  • CSAPP 7.6 - 7.7
• Lecture
  • L16-linking
    • Handwritten diagram & notes

Lecture 20: W 4/8

Linking (continued)

• Lecture
  • L16-linking
    • Handwritten diagram & notes
• Source code:
  • hello

Lecture 21: M 4/13

Linking (continued)

• Lecture
  • L16-linking
    • Handwritten diagram & notes
• Source code:
  • echo1

Lecture 22: W 4/15

Linking (continued)

• Lecture
  • L16-linking
    • Handwritten diagram & notes
• Source code:
  • echo2
  • sum

Linking 2

• Reading
  • CSAPP 7.10 - 7.14
• Lecture
  • L17-linking-2
• Source code

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Last updated: 2026-04-01