Description
PREWORK
Login Tools
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PuTTY
Editors
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vim FTP Tools
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FileZilla Client
PuTTY
Download PuTTY
PuTTY
How to Use PuTTY
Login
The default for SSH service is port 22
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bsd1.cs.nctu.edu.tw – bsd5.cs.nctu.edu.tw
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linux1.cs.nctu.edu.tw – linux6.cs.nctu.edu.tw
PuTTY
Command
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clear – clear the screen
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ls – list directory contents
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mv – move files or directories
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mkdir – create directories
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rm – remove files or directories
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chmod – change file system modes of files or directories
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Other instruction Reference
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http://linux.vbird.org/linux_basic/redhat6.1/linux_06command.php#filesystem
FileZilla
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Upload File to Workstation
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Login
主機: bsd1.cs.nctu.edu.tw
協定: SFTP
登入型態: 一般
使用者: 計中申請帳號
密碼: 計中申請密碼
HW 1-1
Finish “hw1_1.c” in order to design a C program to serve as a shell interface that accepts user commands then execute each command in a separate process.
UNIX shells typically allow the child process to run in the background or concurrently, so if a ampersand(&) at the end of the command means the parent and child processes will run concurrently.
You will use:
read(STDIN_FILENO, inputBuffer, MAX_LINE): read command line
fork(): create child process
execvp(char *command, char *params[]): execute system calls wait()
waitpid(pid)
…
HW 1-1
• Change directory
$cd your/folder/
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Compile
$gcc -o shell hw1_1.c
• Execute
$./shell
• You need
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finish “hw1_1.c” as a shell interface.
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user can keep entering the command until he/she enters “exit”.(a command include the command itself and its parameters).
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if a user enter “&”, the shell should let child run in the background (means child and parent run concurrently).
Example
Show the content of hi.txt file 
Show the file in the directory
Show the date 
List all processes in current shell
Perform a full-format processes list 
Enter “exit” to finish shell 
Example
Receive “-ael” as args and execute
Example
PID 15771&16230 becomes a zombie
(because ps –f & will let child process and parent process run concurrently, meaning that the parent process didn’t call “wait” for the child)
HW 1-2
Please draw the tree format according the code on the report(OS_document.docx).
You need to clarify which fork(fork0, fork1, fork2 or fork3)
the process been made by, for instance:
main
fork0
process
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fork1 |
fork2 |
fork2 |
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… |
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HW 1-3
Write a program which uses fork() to produce the following tree format (namely, your code should have only 3 fork())
Main fork3
fork1 
Child
Child fork3
fork2 Child
Child fork3
Child
Time
HW 1-3
Output format
Main process 
Total 5 Children
The format & fork order
have to be same.
(Fork 1 2 3 3 3)
Hint:
Parent Process has to wait until Child Process finishes, then exit.
Use PID to identify parent and child.
Hint
Submission and Grade
Filename format please according : hw1-1.c, hw1-3.c (or .cpp), OS_report.docx. Put two *.c(*.cpp) files and a *.docx report into same compressed file named StudentID_hw1.zip (ex : 0000000_hw1.zip).
Deadline: 2018/10/14 (SUN) PM11:59
a. Total score: 100pts. COPY WILL GET A 0 POINT!
b. hw1-1 score: code 40pts, report Q1 10pts
c. hw1-2 score: report Q2 20pts
d. hw1-3 score: code 20pts, report Q3 10pts
e. Report: format is in OS_report.docx. YOU NEED TO FINISH EVERY PART OF REPORT TO GET SCORE!
Rules
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Use NCTU CS Workstation as your programming environment
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Use only C/C++, OTHER LANGUAGES WILL GET 0 POINT!
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Incorrect filename format will get -5 pts
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Incorrect output format will get -5 pts
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DELAYED SUBMISSION WILL GET 0 POINT!
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*If you have any question, just send email to TAs.
