LPI 101-500 Exam With Confidence Using Practice Dumps

The most likely reason for getting an error when creating a hard link to an ordinary file is that the source and the target are on different filesystems. A hard link is a directory entry that points to the same inode as the original file. An inode is a data structure that stores the metadata and location of a file on a filesystem. A hard link cannot span across different filesystems because each filesystem has its own inode table and numbering scheme. Therefore, a hard link can only refer to a file that exists on the same filesystem as the link. This is mentioned in the article by How-To Geek1 and the man page of ln2. The other options are not valid reasons for getting an error when creating a hard link. The source file being hidden, read-only, or a shell script does not affect the ability to create a hard link, as long as the user has the appropriate permissions. The source file being already a hard link also does not prevent creating another hard link to the same file, as long as the maximum number of links per inode is not exceeded. This is explained in the article by Linuxize3 and the man page of ln

The /proc/ directory is a virtual filesystem that provides a view of the kernel’s data structures and parameters. It contains information about processes, hardware, memory, modules, and other aspects of thesystem. The files in /proc/ are not stored on disk, but are generated on the fly by the kernel when they are accessed. Therefore, any changes to files in /proc/ are immediately recognized by the kernel and affect its behavior. For example, writing a value to /proc/sys/kernel/hostname will change the system’s hostname without rebooting. The files in /proc/ are not all read-only; some of them can be modified by the root user or by processes with the appropriate permissions. The files in /proc/ are readable by any user, unless restricted by the kernel or by the mount options. References: LPI Linux Essentials - 1.101.2, LPI Linux Administrator - 102.3

The directories on a 64 bit Linux system that typically contain shared libraries are /usr/lib64/ and /lib64/. Shared libraries are binary files that provide reusable functions, routines, classes, data structures, and so on for programs and applications. They are loaded into memory before the program starts and shared by multiple processes that use the same library. Shared libraries are usually stored in standard locations in the file system, such as /usr/lib, /usr/local/lib, /lib, and /lib64 for 32 bit systems, and /usr/lib64, /usr/local/lib64, /lib64, and /lib for 64 bit systems12. The /usr/lib64 and /lib64 directories contain the shared libraries for the system and user applications, respectively. The other directories are either non-existent or do not contain shared libraries. The ~/.lib64/ directory is not a standard location for shared libraries, and it is unlikely that a user would have such a directory in their home directory. The /var/lib64/ directory is also not a standard location for shared libraries, and it is usually used for variable data files that are specific to a package or application. The /opt/lib64/ directory is not a standard location for shared libraries, and it is usually used for optional software packages that are installed in the /opt directory3. References:

• Linux Essentials - Linux Professional Institute Certification Programs1
• Exam 101 Objectives - Linux Professional Institute2
• Understanding Shared Libraries in Linux - Tecmint3