Pass the RedHat RHCT RH033 Questions and answers with ExamsMirror

You will use find -name foobar.png command to do case-senstive search for files named foobar.png.

What is the find command?

The find command can perform a search based on a variety of search limitations. It searches through one or more directory tree(s) of a filesystem, locating files based on some user-specified criteria. By default, find returns all files in the current working directory. Further, find allows a user to specify an action to be taken on each matched file.

Thus, it is an extremely powerful command for applying actions to many files.

The find command can be used with a wild card (*), but it works best when we know the name of the file or directory we are looking for.

The find command can search your system for files that comply with certain numeric criteria, such as the size of the file (-size), the number of links to the file (-links), the date of the last change to the files data (-mtime), or the date of the last time the file was read (-atime). All these criteria accept a numeric value. When a numeric value is provided to find, it looks for an exact match, more than the number, or less than the number.

Answer option B is incorrect. The find -iname foobar.png command will do case-insensitive search for files named foobar.png.

Answer option C is incorrect. The grep-name foobar.png is an invalid command.

What is the grep command?

The grep command is used to search for a specific pattern of text in a file. It helps administrators in searching large amounts of text for a certain error message or name.

Answer option A is incorrect. The locate -name foobar.png is an invalid command.

What is the locate command?

The locate command is used to search for matching files in a database that is usually updated daily by a cron job. On the forthcoming Linux operating systems, this command is usually replaced by the slocate command, which stores permissions as well as paths and thus prevents users from prying into directories. One more advantage of the locate command is that it matches against any part of a pathname, not just the file itself.

The less command is most useful for viewing large files. The less command displays the output of a file one page at a time. Viewing large files through cat may take more time to scroll pages, so it is better to use the less command to see the content of large files.

Answer option B is incorrect. The cat command is also used to view the content of a file, but it is most useful for viewing short files.

Answer option A is incorrect. The cp command is used to copy files and directories from one location to another.

Answer option D is incorrect. The touch command is not used to view the content of a file. It is used to create empty files or to update file timestamps.

The evince utility is used to view the PDF files in Linux.

Answer option A is incorrect. The ps2pdf utility creates the PDF files.

Answer option C is incorrect. The pdf2ps utility converts the PDF files to PostScript.

Answer option B is incorrect. The a2ps utility converts text to PostScript and sends it to the print queue or file.

This command looks for files on the system whose data has been changed exactly five days ago.

The cat data.txt.* command will display both the splitted files, and the > command will redirect the output into a new data.txt file.

What is the cat command?

The concatenate (cat) command is used to display or print the contents of a file.

Syntax: cat filename

For example, the following command will display the contents of the /var/log/dmesg file: cat /var/log/dmesg

Note: The more command is used in conjunction with the cat command to prevent scrolling of the screen while displaying the contents of a file.

What is > command?

The > command is used for storing the output generated by different commands. It creates a file specified to store the output. If the specified file already exists, it overwrites that file.

Answer option A is incorrect. This command will open a new file data.txt.* into the vi editor.

Answer option D is incorrect. This command will give the vi editor a warning "output is not to a terminal" since the vi terminal cannot be redirected into the data.txt file.

Answer option B is incorrect. The less command displays only the first file data.txt.aa, and the > command redirects the output into the data.txt file. Hence, John will not get the desired output using this command.

Kernel files do not change regularly and therefore are contained in the /boot directory, not in the

/var directory.

What is the /var directory?

According to the Filesystem Hierarchy Standard, the /var directory contains regularly-changing system files. This comprises spool directories and files, and administrative and logging data.

Answer option A is incorrect. System log files are stored in the /var directory.

Answer options D and C are incorrect. Print spool files and email-spools are variable data files and therefore are contained in the /var directory.

The rm *[0-9] command deletes all files whose names end with a number.

Answer option B is incorrect. The rm [^0-9] command deletes all files except those having names ending with a number.

Answer option C is incorrect. The rm ^[0-9] command deletes all files whose names begin with a number.

Answer option D is incorrect. The rm [0-9]* command also deletes all files whose names begin with a number.

In order to accomplish the task, you will have to kill the process and rerun it by using the nice command to lower the priority of the process.

You will have to run the following command: kill : nice -n 19

The nice command is used to run a process with the desired priority level. The priority level varies from 1 to 19. Level 1 is for the highest priority and level 19 is for the lowest. By default, every process runs with the priority level 10.

Answer option C is incorrect. The fg command is used to run a process in the foreground.

Answer option D is incorrect. The bg command is used to run a process in the background.

Answer option A is incorrect. The -n 1 switch will provide the process the top priority.

aspell is a utility that can function as an ispell -a replacement, as an independent spell checker, as a test utility to test out Aspell features, and as a utility for managing dictionaries.

Syntax:

aspell [options]

Some important options used with aspell are as follows:

The following options may be used with the aspell command to control which dictionaries to use and how they behave:

Answer option A is incorrect. The tee command is used to split the output of a program so that it can be seen on the display and also be saved in a file. It can also be used to capture intermediate output before the data is altered by another command or program. The tee command reads standard input, then writes its content to standard output, and simultaneously copies it into the specified file(s) or variables.

The syntax of the tee command is as follows: tee [-a] [-i] [File] where, the -a option appends the output to the end of File instead of writing over it and the -i option is used to ignore interrupts.

Answer option B is incorrect. The concatenate (cat) command is used to display or print the contents of a file.

Syntax:

cat filename

For example, the following command will display the contents of the /var/log/dmesg file:

cat /var/log/dmesg

Note: The more command is used in conjunction with the cat command to prevent scrolling of the screen while displaying the contents of a file.

Answer option D is incorrect. There is no such utility as dict in Linux.

This command will execute a program named My_program and whatever errors are generated while executing that program will all be added to a file named file2 rather than being displayed on the screen.

What is redirection of STDIN, STDOUT, STDERR in Linux?

Redirection means diverting data from their normal destination to another. Whenever a program is executed on terminal some output is displayed at the shell prompt. In case a user does not want that output to appear in the shell window, the user can redirect it elsewhere. The user can redirect the output into a file, printer, etc.

Not only the output of programs is redirected, but also input of a program and error messages are redirected to a file.

Common Redirection operators are as follows:

Answer option D is incorrect. This command will direct the standard output of My_program to file2.

Answer option A is incorrect. This command will append the standard output of My_program to file2.

Answer option C is incorrect. This command cannot be applied in this scenario.