Week 13

Question 1

What does a version control system do?

Answer 1

Tracks changes to source code

Helps integrate your changes with changes from someone else

Lets you manage parallel streams of development on the code

Question 2

What are the two types of version control system approaches?

Answer 2

Centralized vs distributed control

Question 3

What are the differences between centralized and distributed version control systems?

Answer 3

Both have the concept of a master repository

Centralized control runs all the major commands and log information through the master repository.

Distributed places a more extensive copy of the history in the local working copy.

Question 4

Which of the two types of version control systems are better for online and offlie operations

Answer 4

Centralized is better if you have access to online

Distributed makes working offline easier, but merging revisions can require more complex algorithms

Question 5

Which of the two types of version control systems are more convenient for users?

Answer 5

The distributed is more easy for users, but te centralized is easier to manage and build.

Question 6

Describe the lock-modify-unlock system

Answer 6

You can exclude other uses from accessing a file by locking it. It also serializes all changes to the files. There are no conflicts because only one person can access at a time.

Question 7

Describe the copy-modify-merge mode of operation?

Answer 7

You can get your own editable copy of the file and change as you like.

Merge your changes with everyone elses when you’re ready

Question 8

What is a trunk?

Answer 8

The one main stream of development

Question 9

What is a branch?

Answer 9

Side-development projects

Question 10

What is a tag?

Answer 10

STable checkpoints that you might want to call back

Question 11

What is a merge?

Answer 11

Sometimes the branch recombines with the trunk.

Question 12

What belongs in a version control system?

Answer 12

Anything that is an original document.

source code
Documentation
supporting images

Question 13

What doesn’t belong in a version control system?

Answer 13

Anything that is derived.
Object files
pdf files
executable files

Question 14

What does svn stand for?

Answer 14

Subversion

Question 15

What behaviour mode does subversion have?

Answer 15

copy-modify-merge

Question 16

What are the two types of branch merging?

Answer 16

Bring updates from the trunk into a branch

Migrate a branch to the trunk and close the branch

Question 17

What are the steps to bring updates from the trunk into a branch?

Answer 17

• Called a sync merge
• Commit all the branch changes to the branch repository
• Use the ‘svn merge’ command to bring over the content from the trunk
• Commit the update to the branch

Question 18

What are the steps to migrate a branch to the trunk close the branch?

Answer 18

• Called a reintegrate merge
• commit all the branch changes to the branch repository
• get a copy of the trunk
• Use the svn merge –reintegrate command to move all the branch content to the trunk and close off the branch
• resolve any conflicts to commit the merge to the trunk

Question 19

What do changelists do?

Answer 19

Let you make lists of files that are being modified for a common reason

Question 20

What the purpose of a changelist

Answer 20

Lets you ask for status and commit on just those files

Question 21

How do we create a changelist?

Answer 21

svn changelist listname file1 file2

Question 22

What are the commands for file locking?

Answer 22

svn lock
svn unlock
can steal a lock from someone else with the –force flag

Question 23

How do we get more information on a svn file?

Answer 23

svn info

Question 24

Ignoring files?

Answer 24

svn propset svn:ignore pattern_to_ignore target_repository

Question 25

What do shells like bash allow you to do?

Answer 25

Write programs in them too

Question 26

What is a shell program called?

Answer 26

A script

Question 27

When are scripts typically used?

Answer 27

Created to automate some process that involves invoking a sequence of programs

Question 28

A script is as simple as what?

Answer 28

A text file with commands to execute. Usually one command per line.

Question 29

what are the three ways we execute a script?

Answer 29

1) Read in the text to your current shell
2) Invoke the shell (a new instance) and pass the script as a parameter)
3) Make the script act like a program of its own

Question 30

How are command line arguments accessed?

Answer 30

With the variable names $1, $2

Question 31

What are the semantic elements for any language?

Answer 31

Variables
expressions
conditionals/selection
Loops

Question 32

What is a subshell?

Answer 32

Within a script, you can execute another program or script in its own shell using the back quotes