Software engineering is a growing sector. Getting specialization in any of the software skills can yield you high rewards. The job of a UNIX Engineer is to know, monitor and program all the specifications related to UNIX environment. Competent and strong programming skills are needed for this profession.
I am providing few important interview questions that are mainly asked by an employer:
1. Define kernel.
The kernel is the first part of the operating system that loads while booting. It constitutes the central core of the operating system. It does not interact directly with the user but interacts with shell and other programs on the system. It remains continuously in the memory and hence its size should be small enough. It is loaded in a protected area which prevents it from being overwritten.
2. What is the difference between soft link and a hard link?
ln command is used to create symbolic link in the file system. A hard link is like a pointer. It is a link which points directly to a specific inode on the same file system. A soft link is like a shortcut as in Windows. It is a symbolic link to another file either on the same file or different file system. A symbolic or soft link can link to any file on a network and can even link to directories while a hard link can only link to files on the same file system.
3. In which language is UNIX written?
UNIX has been written in C. It is portable and can run on computers and microprocessors both. The source code has been written in high level language which makes it adaptable with specific requirements.
4. In what ways can you find free space in UNIX/Linux?
There are two commands that can do this job:
First is the df command. It displays the amount of disk space that has been occupied by mounted or unmounted file systems. It gives information about the available space and the amount used. df-h will give the output in human readable format. Second way is to use du command. du stands for disk usage. It tells the number of kilobytes used by each sub directory in current path.
5. Which command is used to change the authorization of files and folders?
The command used for giving or changing the permission of files and folder is chmod. The syntax for the command is:
chmod <category> <operation><permission> filename.
These are some of the important interview questions that are mainly asked by an employer. All the best!
