COP4342 Final Exam
What constitutes a valid filename in Unix? Any alphabetic or numeric character, underscores, dashes, or period All characters Only letters and numbers. All characters but the file name must not start with a \
Any alphabetic or numeric character, underscores, dashes, or period
Match the regular expression on the left with the description on the right for sets using \{ and \} ^*
Any line starting with an *
Match the Regular Expression on the left with the description on the right. [0-9\-a\]]
Any number, of a "-", a "a", or a "]"
Copying and editing text in Emacs can be one through the mouse ( if you have xming running ) or through the keyboard commands. What are the keyboard commands to mark, cut and paste text. esc-@ to mark the text esc-c to cut the text esc-p to paste the text Ctl-@ marks the text Ctl-w kills or grabs the text Ctl-y to paste :@ to mark text Command-C - to cut the text Command-P - to paste the text Ctl-^^ to mark text Ctl-K to cut Ctl-U to paste
Ctl-@ marks the text Ctl-w kills or grabs the text Ctl-y to paste
How do you determine the cursor current position in the Pico editor? The position is shown at the bottom of the page. You must physically count the lines and characters. Pico is too primitive. Select the menu option that shows the status. Ctl-C
Ctl-C
The Pico Editor was created before arrow keys were common on keyboards. What other keyboard inputs allow you to move the cursor around the screen? Ctl-V, Ctl-Y, Ctl-K, Ctl-H F, B, P, N Ctl-F, Ctl-N, Ctl-P, Ctl-B Alt-F, Alt B, Alt-P, Alt-N
Ctl-F, Ctl-N, Ctl-P, Ctl-B
What keyboard sequence allows you to save and exit the Pico editor? Ctl-O Ctl-X Ctl-A Ctl-B Ctl-^ Ctl-^ Ctl-s Ctl-X
Ctl-O Ctl-X
To search forward in Emacs for a string of text you type in what command? esc-S :S Ctl-s :Seach->
Ctl-s
Positional or "Read Only" parameters are used to pass parameters to shell scripts. The first parameter $0 always contains what? The first parameter The number of parameters The name of the script that is being run The PID number of the process
The name of the script that is being run
The vertical bar in a regular expression "|" is used to describe alternative selections of two or more. True False
True
Which Regular Expression matches at least one digit followed by zero or more digits? [0-9][0-9]* [0-9] [0-9][0-9] [0-9^]
[0-9][0-9]*
Which regular expression will match a single upper or lower case letter or a digit? {a-zA-Z0-9} <a-zA-Z0-9> [a-zA-Z0-9} (a-zA-Z0-9)
[a-zA-Z0-9}
You can append and overwrite text in the Vi editor by pressing the following corresponding keys: :a for append after cursor :A for append at the end of line :r for replace single character under cursor :R for replace characters starting at current position a for append after cursor A for append at the end of line r for replace single character under cursor R for replace characters starting at current position o for append after cursor O for append at the end of line a for replace single character under cursor A for replace characters starting at current position Ctl-a for append after cursor Ctl-A for append at the end of line Ctl-r for replace single character under cursor Ctl-R for replace characters starting at current position
a for append after cursor A for append at the end of line r for replace single character under cursor R for replace characters starting at current position
Match the Regular Expression on the left with the description on the right. [^0-9]
any character other than a number
Match the regular expression on the left with the description on the right for sets using \{ and \} ^A\{4,8\}B
any line starting with 4,5,6,7,or 8 "A"s and ending in a "B"
Match the regular expression on the left with the description on the right for sets using \{ and \} *
any line with an asterick
Match the regular expression on the left with the description on the right for sets using \{ and \} ^AA*B
any line with one or more "A"s followed by "B"
Match the Regular Expression on the left with the description on the right. [0-9]]
any number followed by a ]
Match the Regular Expression on the left with the description on the right. [-0-9]
any number of a "-"
What does the following statement print? for I in 7 9 2 3 4 5 ; do echo $I done d. Prints all numbers between 2 and 9 a. Prints the numbers 7, 9, 2, 3, 4, and 5 on one line c. Prints the number 2, 3, 4, 5, 7, and 9 in order b. Prints the number 7, 9, 2, 3, 4 and 5 on separate lines
b. Prints the number 7, 9, 2, 3, 4 and 5 on separate lines
How do you know if a file is hidden in unix? a.It is marked with an h in the directory list structure b. The file name begins with a . (dot) c. It shows up as a lightly colored font. d. Hidden files cannot be seen.
b. The file name begins with a . (dot)
What statement in bash script checks to see if there is at least one parameter? a. if test $# -gt 0; then b. if [ ! "$1" == "" ]; then Both of the options None of the options
b. if [ ! "$1" == "" ]; then
Which file or files contain the location of the current working directory? a. The file curr-dir b. hidden file called .dir c. The file with the name of only a single dot (.) d. The file that has the name of two dots (..)
c. The file with the name of only a single dot (.)
Which command displays the current month's calendar in Unix? currcal calendar date -calendar cal
cal
Which command displays the calendar for the current, previous and next month in Unix? Calendar -3 cal -3 currcal -3 date -3
cal -3
What command displays the entire calendar for the year 1955 in Unix? currcal 1955 date 1955 cal 1955 Calendar 1955
cal 1955
What is the command that copies all of the current files that end in .txt to a directory just below the parent directory called Assign2? cp *.txt /Assign2/*.txt cp *.txt .././Assign2/*.txt cp *.txt ../Assign2/ copy *.txt ../Assign2/
cp *.txt ../Assign2/
Which command copies a file called myfile.txt to a subdirectory called Assignment1Dir leaving the name the same? copy myfile.txt Assignment1Dir/myfile.txt cp myfile.txt Assignment1Dir/myfile.txt copy myfile.txt Assignment1Dir..myfile.txt cp myfile.txt /Assignment1Dir > myfile.txt
cp myfile.txt Assignment1Dir/myfile.txt
To change to the parent directory of the current directory you are in, you type which command: a. cd .dir b. cd /~username c. cd .prev d. cd ..
d. cd ..
Which command displays the value of the shell variable MYNAME to standard ouptut? lprint $MYNAME; $MYNAME echo $MYNAME cout << $MYNAME;
echo $MYNAME
Match the character with it's meaning $
end of string
Match the character with it's meaning *
end of string
To change case in emacs you can use the following commands: :u Changes word to uppercase :l changes word to lowercase :c capitalize word Select word and hit the Caps Lock to change word to upper case. Select word and toggle the Caps Lock to change word to lower case Select word and hit the shift key to capitalize word Ctl-u Changes word to uppercase Ctl-l changes word to lowercase Ctl-c capitalize word esc-u Changes word to uppercase esc-l changes word to lowercase exc-c capitalize word
esc-u Changes word to uppercase esc-l changes word to lowercase exc-c capitalize word
Match the character with it's meaning ?
exactly one character
How or what command do you use to stop a script? exit stop quit return
exit
Which command is used to create a file called myfile.txt but only if it does not exist? touch -l myfile.txt touch -n myfile.txt touch -c myfile.txt touch -m myfile.txt
touch -c myfile.txt
Which command will change the date and time of a file called myfile.txt to the current time and date? update myfile.txt mv -m myfile.txt touch -m myfile.txt reset myfile.txt
touch -m myfile.txt
Which one of the following commands creates a file callled myfile.txt with an empty content? myfile.txt << touch myfile.txt >> myfile.txt Create myfile.txt
touch myfile.txt
What is the command to display the word count of a file showing the number of bytes, number of lines, and number of words wc- c wc wc -l wc -w
wc
What is the command to show the number of characters in a file? wc wc -w wc -l wc -c
wc -c
What is the command to show the number of lines in a file? wc -c wc -w wc -l wc
wc -l
What Unix command that prints to standard output the current username? MyName PS whoami whatsmyname
whoami
Deleting characters and text also uses keyboard commands. Which of the following allows users to delete characters, words and lines in the Vi editor. Ctl-x - Delete a single character Ctl-dw - Delete a single word Ctl-Ctl-dd - Delete the current line Ndd - Delete N number of lines starting at the current. :x - Delete a single character :dw - Delete a single word :dd - Delete the current line :Ndd - Delete N number of lines starting at the current. x - Delete a single character dw - Delete a single word dd - Delete the current line Ndd - Delete N number of lines starting at the current. esc-x - Delete a single character esc-dw - Delete a single word esc-dd - Delete the current line esc-Ndd - Delete N number of lines starting at the current.
x - Delete a single character dw - Delete a single word dd - Delete the current line Ndd - Delete N number of lines starting at the current.
Positional or "Read Only" parameters are used to pass parameters to shell scripts. This parameter contains the number of parameters entered for a script: $1 $* $# #@
$#
Positional or "Read Only" parameters are used to pass parameters to shell scripts. This variable will contain the string of the entire command entered to execute the script. $@ $* #0 $#
$*
The wild card character that allows you to match 0 or more characters in a file search is which of the following: ? $ # *
*
To save and exit in the vi editor you enter the following command key sequence: Ctl-W Ctl-Q :q! :x :wq
:wq
The character that allows you to match only a single character in file searches is which of the following: ? @ * #
?
In a shell script, one of the first lines of code that define the shell that will execute the script ( like #!/bin/bash) is called what? A shebank or shabang It has no formal name. A hashtag The mother script
A shebank or shabang
Which of the following is a Unix Shell? tcshrc All of these answers. bourne cshell korne
All of these answers.
To move the cursor around in Emacs you can use which of the following keyboard commands as an alternative to the arrow keys? esc-u - Up one line esc-d - Down one line esc-f - Forward one character esc-b - Backward one character l key - Forward one character h key - Backward one character v key - Forward one line y key - Backward one line 8 key - Up one line 2 key - Down one line 6 key - Forward one character 4 key - Backward one character Ctl-b Back one character Ctl-f Forward one character Ctl-n Forward one line Ctl-p Backward one line
Ctl-b Back one character Ctl-f Forward one character Ctl-n Forward one line Ctl-p Backward one line
To read a file in unix into the Emacs file your are editing you type in the following keyboard command followed by the filename: Ctl-x Ctl-f Ctl-R Ctl-O esc-x esc-f :rf
Ctl-x Ctl-f
To undo a modification in Emacs you enter which of the following: Ctl-x u Ctl-u :xu Ctl-x Ctl-u
Ctl-x u
What is the difference between and local and environment variable? Environment variables are available to any child process or the instance of the shall...local variables are not. Local variables can only be used inside of scripts. There are no differences. Environment variables are defined by the System Administrator and not by the user.
Environment variables are available to any child process or the instance of the shall...local variables are not.
What is the difference between and local and environment variable? There are no differences. Environment variables are defined by the System Administrator and not by the user. Local variables can only be used inside of scripts. Environment variables are available to any child process or the instance of the shall...local variables are not.
Environment variables are available to any child process or the instance of the shall...local variables are not.
You cannot match any single character in a regular expression. It must be zero or more. True False
False
To select and cut text in Vi you use the following procedure: :yy to yank or copy the current line into the buffer :Nyy to yank the next N lines into the buffer :p to paste the text. Ctl-yy to yank or copy the current line into the buffer Ctl-Nyy to yank the next N lines into the buffer Ctl-p to paste the text. In command mode: yy to yank or copy the current line into the buffer Nyy to yank the next N lines into the buffer p to paste the text. esc-yy to yank or copy the current line into the buffer esc-Nyy to yank the next N lines into the buffer esc-p to paste the text.
In command mode: yy to yank or copy the current line into the buffer Nyy to yank the next N lines into the buffer p to paste the text.
When you list the content details of a directory the first column contains a series of dashes and letters associated with a file. What would be the meaning of the following entry? -rwxrwx- - - It indicates how deep within the current device the file is located. It is not a directory, the Owner and Group of Read, Write, and Execute privileges, the world has no privilege. It identifies the owner of the file Every has read, write and execute privilege.
It is not a directory, the Owner and Group of Read, Write, and Execute privileges, the world has no privilege.
Which command defines a variable called MYNAME and assigns the name Dr. Zhivago to it in a bash script? $MYNAME=Dr. Zhivago Assign MYNAME=Dr. Zhivago MYNAME="Dr. Zhivago" $MYNAME="Dr. Zhivago"
MYNAME="Dr. Zhivago"
Which command assigns the first name of characters from the Movie Dr. Zhivago to the variable array called NAMES in a bash script? NAMES=(Yuri Lara Pasha Tonya) NAMES[1]=pasha NAMES[2]=Lara NAMES[3]=Pasha NAMES[4]=Tonya NAMES[1..4]=Lara, Yuri, Pasha, Tonya set NAMES[1..4]=Yuri, Lara, Pasha, Tonya
NAMES=(Yuri Lara Pasha Tonya)
To cut and paste a selected area in the Pico ediitor you must use the following keyboard commands: Once the area is selected you press the Command-C to cut the text and Command -V to paste t. Once the area is selected you press the Ctl-C to cut the text and Ctl-V to paste it. Once the area is selected you press the Ctl-K to cut and then Ctl-K again to paste it. Once the area is selected you press the Ctl-K to cut and Ctl-U to paste.
Once the area is selected you press the Ctl-K to cut and Ctl-U to paste.
Marking and selecting text in Pico is somewhat unique. To start selecting text you must mark the beginning. How is this done? Place the cursor in the start of the text and press Ctl-U Place the cursor in the start of the text and press Ctl-K Use the mouse to place the cursor in the beginning of the text. Place the cursor in the start of the text and press Ctl-^
Place the cursor in the start of the text and press Ctl-^
The undo command in Vi is: Press the u key in command mode Ctl-u or Ctl-U :cu :u
Press the u key in command mode
Unix variable names can contain what? The name of a variable can contain only letters (a to z or A to Z ), numbers (0 to 9) or the underscore (_). Any character on the keyboard. Unix variable names have the same syntax rules as C and C++ variable names. Only letters.
The name of a variable can contain only letters (a to z or A to Z ), numbers (0 to 9) or the underscore (_).
To get help in emacs you: Enter Ctl-g or Ctl-G Select the question mark. Type Help in command mode Type Ctl-h or F1
Type Ctl-h or F1
How would you delete a Unix variable? Use the rm command. Use the unset command or assign it a blank/empty string. Assign the variable blanks. Use the delete command.
Use the unset command or assign it a blank/empty string.
How do you set an environment variable? Set the variable with the -e option. Using the setenv command Environment variables must be set by someone with root access. Using the set command in the .login script.
Using the setenv command
What is the command to display the complete contents of a file called myfile.txt while showing the line numbers? show -l myfile.txt cat -n myfile.txt show myfile.txt cat myfile.txt
cat -n myfile.txt
Which sed command replaces the word '"ford" with the word "Ford" in the file cars. Select all that apply. There might be more than one. sed -f cars 's/ford/Ford/' cat cars | sed 's/ford/Ford/' sed 's/ford/Ford/' cars sed 's/ford/Ford/' < cars
cat cars | sed 's/ford/Ford/' sed 's/ford/Ford/' cars sed 's/ford/Ford/' < cars
sed command that only prints the records that have the word "ford" in it? car cars | sed /ford/p cat cars | sed G sed '/ford/p' cars cat cars | sed -n '/ford/{p}'
cat cars | sed -n '/ford/{p}'
What sed command double spaces the output of the file cars? sed -/\n/i' cars cat cars | sed G sed -d cars sed '/^*/'d cars
cat cars | sed G
Which statement searches for any word or string that ends in "ord" and begins with only a single character in the file cars. grep "@ord" cars grep ".ord" cars grep "*ord" cars grep "$ord" cars
grep ".ord" cars
Which search using grep looks for the whole word "the" or "The" amd not just the occurance of the letters in the file road.txt. grep "[tT]he" road.txt grep "%[tT]he" road.txt grep "^[Tt\he" road.txt grep "\<[tT]he\> road.txt
grep "\<[tT]he\> road.txt
Which command searchs for the word "ford" at the beginning of a line in the file cars? grep "ford" cars grep "^ford" cars grep ".ford" cars grep "$ford" cars
grep "^ford" cars
Which command searchs for the word "ford" at the end of a line in the file cars in a bash script? grep "00^" cars grep "00" cars grep "ford$" cars grep "ford." cars
grep "ford$" cars
Which command matches zero or more characters characters that have the word "the" in the file road.txt? grep "the$" road.txt grep "the*" road.txt grep "the." road.txt grep "the&" road.txt
grep "the*" road.txt
What regular expression looks for any alphabetic character upper or lower case in road.txt? grep [a-zA-Z] road.txt grep [A-z] road.txt grep [a-Z] road.txt grep [a-z,A-Z] road.txt
grep [a-zA-Z] road.txt
To put the vi editor in insert mode you press which key? i I Ctl-I Ctl-i
i
Assume you have a variable name MYFILENAME. Which statement tests to see if the string contained in MYFILENAME exists as a file. if (-e $MYFILENAME) then echo "File Exists" endif if (-r $MYFILENAME) then echo "File Exists" endif if (-s $MYFILENAME) then echo "File Exists" endif if (-w $MYFILENAME) then echo "File Exists" endif
if (-e $MYFILENAME) then echo "File Exists" endif
Assume you have a variable name MYFILENAME. Which statement tests to see if the string contained in MYFILENAME is readable? if (-r $MYFILENAME) then echo "Is Readable" endif if (-v $MYFILENAME) then echo "Is Readable" endif if (-w $MYFILENAME) then echo "Is Readable" endif if (-d $MYFILENAME) then echo "Is Readable" endif
if (-r $MYFILENAME) then echo "Is Readable" endif
Moving the cursor around in vi can be done using the cursor keys but can also be accomplished in command mode by using these keys: y,v, h, l ^ ,> , < , | 8, 2, 4, 6 corresponds to the keypad j, k, h, l
j, k, h, l
Type the command that will list all files including hidden file in the current directory.
ls -a
What is the command that will list only the sub-directories in the current working directory: ls -Ad ls -d */ ls -directory * ls -al *
ls -d */
Type the command that will list the details of all the files except hidden files in the current directory:
ls -l
What is the command to display help in Unix? man help Manual Ctl-G ( Hit the Control Key and then the G)
man
Match the regular expression on the left with the description on the right for sets using \{ and \} \\
match any line with a backslash
Which command is used to create directory? mkdir makedir chmod /dir createdir
mkdir
What is the command to display a file one page at a time. display cat more show
more
Which Unix command can be used to rename a file? move mv ren rename
mv
Match the character with it's meaning []
ranges of characters
How would you set a unix variable called MYNAME so that it cannot be changed in a bash script? readonly MYNAME set 444 MYNAME set read MYNAME assignment MYNAME="read"
readonly MYNAME
Match the character with it's meaning .
replaces any single character
Match the character with it's meaning /
represents special characters
Which command can delete a file? del rem rm delete
rm
Which command properly removes a directory called Assign1? deldir Assign1 rm Assign1 rmdir Assign1 removedir Assign1
rmdir Assign1
Which sed command deletes all of the records with the word "ford" at the beginning of the line? sed -d="ford" cars sed -d '/ford/ cars sed '/^ford/d' cars sed '/\+' '/\d' cars
sed '/^ford/d' cars
The command to insert a record before each occurrence where the word "ford" is found? sed '/ford/'kia seltos 2022 85 4560/'i cars sed '/ford/i kia seltos 2022 85 4560' cars sed '/ford/'<<kia seltos 2022 85 4560 cars sed -insert '/ford/' kia seltos 2022 85 4560 car
sed '/ford/i kia seltos 2022 85 4560' cars
Which command suspends execution. zumba chmod kill sleep
sleep
Match the character with it's meaning ^
start of string
Match the Regular Expression on the left with the description on the right. [0]
the character "0"
