Environment Variables in Unix

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What is the correct way to change the value of a variable in a shell?

Use the set command to update the variable value

Specify the variable name followed by a colon and the new value

Use the env command to update the variable value

Specify the variable name followed by an equal sign and the new value (correct)

What is the purpose of the UMASK variable in the BASH shell?

It lists all exported environment and user-defined variables

It performs a specialized function in the shell and must be set by the alias command

It sets the default permissions for newly created files (correct)

It is used to create shortcuts to commands

What is the name given to temporary shells created by the current shell?

Parent shell

Sibling shell

Subshell (correct)

Child shell

Which of the following characters is NOT allowed as the first character of a variable identifier?

Number Signup and view all the answers

What is the purpose of the alias command?

To create and view shortcuts to commands Signup and view all the answers

What is the convention for capitalizing variable identifiers?

They are typically capitalized Signup and view all the answers

What is the purpose of the less command in the pipeline ls –l /etc | less?

To view the output of the ls command page by page Signup and view all the answers

What type of variable is defined by the user in a BASH shell?

User-defined variable Signup and view all the answers

What command is used to view the contents of a specified variable in a BASH shell?

echo command Signup and view all the answers

What type of variables are useful when executing commands and creating new files and directories in a BASH shell?

Special variables Signup and view all the answers

What is the purpose of the pipe character (|) in a command?

To connect multiple commands together Signup and view all the answers

Where are environment variables set by default in a BASH shell?

In the BASH shell itself Signup and view all the answers

What happens to variables stored in memory when you exit a BASH shell?

They are destroyed along with the shell itself Signup and view all the answers

What is the purpose of environment files in BASH?

To make variables accessible at all times Signup and view all the answers

What is the first line in a shell script called?

Hashpling Signup and view all the answers

How can you execute a shell script if you have read permission to it?

By starting another BASH shell and specifying the script as an argument Signup and view all the answers

What is required to execute a shell script like any other executable program on the system?

Both read and execute permission Signup and view all the answers

What is the issue with the output shown in the text?

The output from each command is not separated by blank lines or identified by a label Signup and view all the answers