chapter 1-3 quiz

the -l option causes ls to display its results in long format. this format contains a great deal of useful information. following is the examples directory from an ubuntu system. -rw-r--r-- 1 root root 34391 2017-04-03 11:05 logo-Ubuntu.png -rw-r--r-- 1 root root 32059 2017-04-03 11:05 oo-cd-cover.odf -rw-r--r-- 1 root root 159744 2017-04-03 11:05 oo-derivatives.doc -rw-r--r-- 1 root root 27837 2017-04-03 11:05 oo-maxwell.odt -rw-r--r-- 1 root root 98816 2017-04-03 11:05 oo-trig.xls -rw-r--r-- 1 root root 453764 2017-04-03 11:05 oo-welcome.odt -rw-r--r-- 1 root root 358374 2017-04-03 11:05 ubuntu sax.ogg which of the following is false w.r.t. this information?

** the date and time reflect when the file was originally created

choose all of the following that are true statements

**(try submitting NOTHING/contact prof welty; not getting partial credit for anything i pick) -we can specify pathnames in one of three different ways; as absolute pathnames, as relative pathnames, or as fixed pathnames. -we can specify pathnames in one of two different ways; as absolute pathnames, or as psuedo pathnames -we can specify pathnames in one of three different ways; as absolute pathnames, as relative pathnames, or as defined pathnames true statements: -we can specify pathnames in one of two different ways; as absolute pathnames or as relative pathnames

***(partial)which of the following are true statements?

- the less command is a program to view text files that contain human-readable text. the less program provides a convenient way to examine them. -once started, the less program allows us to scroll forward and backward through a text file -computers only understand numbers and all data is converted to numeric representation

(partial)which of the following are true statements w.r.t absolute and relative pathnames

- where an absolute pathname starts from the root directory and leads to its destination, a relative pathname starts from the working directory -a relative pathname starts from the working directory -a relative pathname uses a couple of special notations to represent relative positions in the file system tree. these special notations are "." (dot) and ".." (dot dot).

which of the following are false statements?

-UNICODE is a simple encoding scheme that was first used on Teletype machines to map keyboard characters to numbers -once started, the more program allow us to scroll forward and backward through a text file

which of the following are false statements w.r.t. directories found on linux systems?

-\lib contains shared library files used by the core system programs -\ represents the root directory. where everything begins -\bin contains binaries (programs) that must be present for the system to boot and run

we can change the working directory from /usr to /usr/bin using

-cd /usr/bin -cd ./bin

choose all of the following, that are true statements

-if you are using a mouse, you can double click on a filename to copy it and middle click to paste it into commands - unlike many proprietary systems, linux makes everything available for examination and study - in linux there are many important files that are plain human-readable text

on linux systems, files are named in a manner similar to other systems such as windows, which of the following are some of the important differences?

-linux has no concept of a "file extension" like some other operating systems. you may name files any way you like - filenames and commands in linux, like unix, are case sensitive. the filenames "File1" and "file1" refer to different files. -filenames that begin with a period character are hidden. this only means that ls will not list them unless you say ls -a. -though linux supports long filenames that may contain embedded spaces and punctuation characters in the names of files you create to period, dash, and underscore. most importantly, do not embed spaces in filenames. if you want to represent spaces between words in a filename, use underscore characters.

choose all of the following that are true statements.

-linux organizes its files in what is called a hierarchical directory structure, organized in a tree-like pattern of directories -linux has a single file system tree, regardless of how many drives or storage devices are attached to the computer -where an absolute pathname starts from the root directory and leads to its destination, a relative pathname starts from the working directory

choose all of the following, that are true statements?

-symbolic links allow files to have multiple names -hard links allow files to have multiple names

most commands use options which consist of a single character preceded by a dash, for example, "-l". Many commands, however, including those from the GNU Project, also support long options, consisting of what?

a word preceded by two dashes

picture this scenario: a program requires the use of a shared resource of some kind contained in a file named "foo," but "foo" has frequent version changes. it would be good to include the version number in the filename so the administrator or other interested party could see what version of "foo" is installed. this presents a program. if we change the name of the shared resource, we have to track down every program that might use it and change it to look for a new resource name everytime a new version of the resource is installed. that doesnt sound like fun at all. which of the following is the best method of addressing this?

create a symbolic link

given that using the absolute and relative pathnames provides for two different methods with identical results, we should use the one that requires more typing.

false

as we explore the system it will be useful to know what files contain. to do this we will use which of the following commands to determine a file's type?

file

what does the following command accomplish? ls ~ /usr

lists both the user's home directory (symbolized by the "~" character) and the /usr directory

which of the following is not a valid command?

ls --forward

if the first letter of a directory listing is "l" and the entry seems to have two filenames, which of the following is true?

this is a special kind of a file called a symbolic link

command options, like filenames in linux, are case-sensitive

true

there are many kinds of files. in fact, one of the common ideas in unix-like operating systems such as lunix is that "everything is a file."

true