Ans: The shell acts as an interface between the user and the operating system. The shell consists of a single operating system that is Kernel this helps to run the scripts simultaneously. When the user enters the command using keyboards, the shell communicates with the kernel operating system and executes it, then displays the output to the users.
Ans: Shell scripting is a series or sequence of Linux commands which are written in plain text format. Shell scripting in Linux is used to list various Linux commands instead of working with specific jobs or commands.
Ans: Below are a few important points which explain the importance of writing shell script such as;
|Is directory||this stores the files in the current|
|mkdir||helps to change the home|
|rmdir||this creates the text known as test|
|cp||this removes the text file|
|rm||this copies the test directory|
|mv files||removes the test directory file|
|more time||this helps to move the directory|
|touch||checks and display the pages at a|
|cat||this displays the content of a file|
|helps to create an empty file|
Ans: There are 4 types of commonly used shells are used in the Linux system they are;
Ans: Soft links are nothing but links, they define the name and store them on different file systems.
Hard Link is also a type of link used to link the inode of the file system and stored on different file systems.
Ans: Shell programs are stored in a file system known as “sh”.
Ans: Below are the advantages of the C shell over the Bourne shell;
Ans: A separate compiler is not required in Linux to execute any shell programs. The shell in Linux interprets the specific commands in the programs and executes the file systems.
Ans: The below instances explain when you should not use shell programming or scripting;
Ans: The two types of shell variables are available such as;
1. User-defined variables or system variables:
These are the standard system variables, generally, they are written with the help of CAPITAL letters.
For example, SHELL: this is Linux defined system variable, which is used to define the name of the working default shells.
2. User-defined variables: These types of variables are defined by users. These are defined with lower case letters.
For example, $ a= 50 where a is the lower case variable and 50 is the value assigned to a.
Ans: Generally, Linux variables are stored as string variables.
Example $ a=50
In the above example, a= 50 where 50 is stored in a variable called a, here a is not considered as a number. The string character can be defined between 1 and 0.
Ans: There are 3 types of file permissions available such as;
Ans: The 4 main block systems available in the Linux file system such as;
|Block name||Name of the block|
|1st block||Boot block|
|2nd block||super block|
|3rd block||Inode table|
|4th block||data block|
Super block: this block is used to define the state of the file system.
Boot block: they define the starting of the file system. It mainly consists of boot strap loader programs.
Inode table: We already know that all the entities in Linux are treated as a file system. Information related to these file systems is stored in Inode tables.
Data block: this block consists of only file contents.
1. Command mode-> in this mode, all the command keys are pressed by a user and then interprets as an editor command.
2. Insert mode-> this type of mode allows users to insert new test types and also edit the existing text file.
3. ex-command mode system-> this type of mode allows users to insert the commands at the command line arguments.