Which of the following commands lists all currently installed packages when using RPM package management?
Correct Answer: E
Explanation
Question 47
What command should be invoked to give the user sally read and write, but not execute, access to the file strategy.txt using Extended ACL entries?
Correct Answer: A
Question 48
Which of the following tools can show the complete path of an executable file that the current shell would execute when starting a command without specifying its complete path? (Choose two.) find
Correct Answer: B,D
Question 49
Which command is used in a Linux environment to create a new directory? (Specify ONLY the command without any path or parameters.)
Correct Answer:
mkdir, /usr/bin/mkdir
Question 50
From a Bash shell, which of the following commands directly executes the instruction from the file /usr/local/bin/runme.sh without starting a subshell? (Please select TWO answers.)
Correct Answer: A,B
Explanation The commands that directly execute the instruction from the file /usr/local/bin/runme.sh without starting a subshell are source /usr/local/bin/runme.sh and . /usr/local/bin/runme.sh. These commands use the source or dot builtins, which read and execute commands from the given file in the current shell environment. This means that any changes made by the file, such as setting variables, defining functions, or changing directories, will affect the current shell. This is different from running the file as a script, which will create a new shell process and execute the commands in a separate environment. The source or dot commands are useful for loading configuration files, such as ~/.bashrc or /etc/profile, or for running scripts that modify the current state of the shell. The other commands are incorrect for the following reasons: * C. /bin/bash /usr/local/bin/runme.sh: This command will run the file as a script using the /bin/bash interpreter. This will create a new shell process and execute the commands in a separate environment. Any changes made by the file will not affect the current shell. * D. /usr/local/bin/runme.sh: This command will also run the file as a script, but using the interpreter specified by the shebang line (#!) at the beginning of the file. If the file does not have a shebang line, it will use the default shell interpreter, which may or may not be /bin/bash. This will also create a new shell process and execute the commands in a separate environment. Any changes made by the file will not affect the current shell. * E. run /usr/local/bin/runme.sh: This command is not valid, as there is no builtin or external command called run. This will produce an error message. References: * [LPI Exam 101 Detailed Objectives], Topic 103: GNU and Unix Commands, Objective 103.1: Work on the command line, Weight: 4, Key Knowledge Areas: Use of source and .. * [Bash Reference Manual], Section 4.2: Bash Builtin Commands, Subsection 4.2.5: Bourne Shell Builtins.
