Praktikum "UNIX"

von Prof. Jürgen Plate

Praktikum UNIX

Sind Sie fit in Unix?

Copyright (c) 1994 Christopher Alexander North-Keys, All Rights Reserved. 

Permission granted for non-profit Internet distribution and perusal only! 

Placement test - Unix operating system.

Incept: Mon Jan 31 09:19:26 CST 1994

Update: Tue Feb 22 23:56:16 CST 1994

Author: Christopher Alexander North-Keys


Easy:    3

Normal: 13

Medium:  6

Hard:    3


Total:  25

Minimum Score:   0

Maximum Score: 250

Par Test Time:   8 minutes, recommend 1

[1 easy] Unix is...

[a] A kind of computer.

[b] An operating system kernel.

[c] A type of graphic interface.

[d] An application program.

[e] A communication protocol.

[2 easy] In order to begin a session of using Unix, one will usually...

[a] Power the machine off, then on.

[b] Just enter the first command.

[c] Convince it that it already knows you, by giving a name and password.

[d] Click and hold the right mouse button, select "Unix", and release.    

[e] Toggle in the bootstrap code on the front panel toggle switches. 

[3 easy] Under Unix, a user often collects information, placing it in...

[a] Documents and folders, calling one of the latter "USER".

[b] Datasets and disk-volumes, calling one of the latter "DEFAULT".

[c] Permanent file sets, accessed by a small integer number.

[d] Files and directories, calling one of the latter "HOME".

[e] 3-1/2 inch (9 centimeter) diskettes.

[4 normal] Once using a Unix system, the most commonly executed program is usually... 

[a] ls.

[b] su.

[c] awk.

[d] cat.

[e] netrek.

[5 normal] Under Unix, a user often edits information interactively, usually using... 

[a] sed, awk, tr, and/or cut.

[b] sos, and/or edt.

[c] Wordperfect. Word, edlin, winedit, and/or the system editor.

[d] teco, tpu, and/or xedit.

[e] vi, emacs, frame, ed, and/or elvis.

[6 normal] A Unix user can invoke commands by name;  the number of command names is... 

[a] Fewer than 5

[b] 5 to 50

[c] 50 to 500

[d] 500 to 5000

[e] Over 5000

[7 normal] A Unix user can often work in a graphic environment, usually called... 

[a] X

[b] SunView

[c] Windows

[d] Desktop

[e] Netrek

[8 normal] An individual Unix system is capable of the following level of operation... 

   Tasks   Users   CPU's   Networks

[a] One   One     One     None

[b] Many  One     One     One 

[c] Many  Many    One     One 

[d] Many  Many    Many    One 

[e] Many  Many    Many    Many

[9 normal] The number of users on the largest mostly-Unix network (the Internet) 

           in Winter of 1994 was around... 

[a] 20,000 or less

[b] 200,000

[c] 2,000,000

[d] 20,000,000

[e] 200,000,000 or more

[10 normal] The following text is...

    char*M,A,Z,E=40,J[40],T[40] ;



      for(*J=A=scanf(M="%d",&C); --E; J[E]=T[E]=E)   


        for(;(A-=Z=!Z) || (printf("\n|"), A=39,C --); 

        Z || printf(M))

        M[Z]=Z[A-(E=A[J-Z])&&!C&A==T[A]|6<<27<rand()||!C&!Z?J[T[E]=T[A]]=E,J[T[A]=A-Z]=A,".":"|"] ;


[a] Just text.

[b] The output of a Unix program called "maze".

[c] An executable script.

[d] A program in a language called "C", a descendent of "B".

[e] A I-node.

[11 normal] To find out the real-life identity of a user, one should usually... 

[a] Read the shadow password file.

[b] Reboot the user's machine, reading the boot messages for sysadm info.    

[c] Run the aliases command.    

[d] Use the nameserver.    

[e] Finger the user in question. 

[12 normal] To get the most information out of the command "ls", one would... 

[a] Append the flag "-all".

[b] Use the options "-Flagsi" (or maybe "-Falsi"?).

[c] Edit the configuration file.

[d] Toggle "all" in the configuration dialog request box.

[e] "ls" is not a Unix command.

[13 normal] Under Unix, the name of a data file may consist of the following. 

    class   defined to be this exact set of characters

    -----   ------------------------------------------

      L     abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ

      D     0123456789P  !@#$%^&*()|-=+[] {};':"`~\?.>,<

      C     Control characters and other unprintables.

      H     Highbit and extended-character-set characters.

[a] L

[b] L, and D

[c] L, D, and P

[d] L, D, P, and C

[e] L, D, P, C, and

[14 normal] Situation:  A SYSV user needs to print the word "hello".He should use...

[a] lp hello

[b] echo hello | lp

[c] lp < hello

[d] hello > lp

[e] cat hello | lp

[15 normal] Situation:  A user is counting with the following code.  In what 

            interpreter would the code function as expected? 

    num=1while [ $num -le 100 ]  ; doecho $numnum=`expr $num + 1`done

[a] rc

[b] sh

[c] perl

[d] csh

[e] awk

[16 normal] In Unix, the two most commonly used editors are vi and emacs. 

            Of these, vi is standard, and emacs is usually imported from 

            the Internet. In the following paired commands (each command 

            in a pair having equivalent function is its respective editor), 

            which pair gives commands for exiting the editor? 

                   Vi Emacs

                   -- -----

[a]^f C-v

[b]:w C-x C-f

[c]!! C-u M-!

[d]ZZ C-x C-c

[e]:r C-x C-i

[17 medium] Which of the following groups might be unreservedly desired by a 

    maniacal Unix guru for home? Assume that a single blatantly undesirable 

    item disqualifies an entire group. 

    group   defined to contain these items

    -----   ------------------------------

      N     TCP/IP  via SLIP on an ISDN or T1 for BSD or SVR4 with 2Gb+ disk.

      G     X, with PEX, XV, TVTWM or OLVWM, Frame, and RenderMan.

      O     TECO-emulation for EMACS via FTP on SVR2 or SVR3 for an AT&T

      C     ARCHIE, GOPHER, WWW (xmosaic), GCC, and the winners of the IOCCC.

      S     USENET mail & GNUS via CU or TIP at 1200 bps (baud) on XENIX.

[a] G, O, and C.

[b] G and C.

[c] N, G, and C.

[d] O and S.

[e] N, C, and S.

[18 medium] Situation:  An underqualified systems administrator has just tried 

            to make a new user account for a Bob Simon using the following 

            commands from the "root" account.  How is the command in error? 

    # cd /home; mkdir "Bob's home directory"

    # echo "Bob Simon:gandalf:0:0::/dev/tty:compress -f" > /etc/passwd

    error   description

    -----   ------------

      H     The argument to mkdir is not a valid name for a new directory.

      I     The login name is invalid, and the password unmatchable.

      P     All pre-existing information in the password file has been lost.

      U     Bob's UID would have made him "root".

      T     The /dev/tty field is only valid on directly-connected terminals.

[a] H, and T.

[b] I, P, and U.

[c] P, U, and T.

[d] H, I, and P.

[e] H, P, and T.

[19 medium] The best description of the operation performed by the command 

            "rm foo" upon the existing filename "foo" is... 

[a] Unlink   - the file has one (of possibly several) links to it cut.

[b] Erase    - the file contents are overwritten with nulls.

[c] Remove   - the file is removed from the disk.

[d] Truncate - the file length is reset to zero.

[e] Purge    - the file is sent to /dev/null.

[20 medium] Situation:  Suppose "foobar" is a software package available on 

the Internet.  A user somewhere on the Internet wishes to obtain and use 

this package.  He does not yet know the appropriate archive to contact.  

The command sequence he will follow will probably be... 

[a] ftp, cd, vi, tar, make, archie, foobar

[b] archie, cd, ftp, vi, make, tar, foobar

[c] ftp, archie, vi, make, tar, cd, foobar

[d] archie, ftp, tar, cd, vi, make, foobar

[e] make, tar, archie, cd, ftp, vi,

[21 medium] A hypothetical utility program called "foobar" might be configured 

at runtime in several ways.  It is not a graphics program.  The most likely 

means of configurations are... 

    method description

    ------ -----------

       E   An environment variable named "FOOBAR".

       P   A pseudo-device file called "/dev/foobar".

       X   A file, ".Xdefaults" or ".Xresources", in the user's home directory.

       K   Reconfig of the system kernel with an entry for the new package.

       F   A file called ".foobarrc" in the user's home directory.

[a] E and F.

[b] E and P.

[c] F and P.

[d] F and X.

[e] P and K.

[22 medium] Certain control characters are typically used in Unix to achieve 

            certain ends, such as indicating end of input, suspending a job, 

            interrupting a job, and so on.  Select the correct line in the 

            following table... 

      suspendend-of-file interrupt         erase

      ------------------ ---------         -----

[a]   ^s^f               ^i or ^k         ^e or ^b

[b]   ^z^d               ^c or ^? (del)   ^? or ^h

[c]   ^q^e               ^a or ^\ (fs)    ^d or ^u

[d]   ^@ (nul)           ^z^b or ^q       ^p or ^u

[e]   ^p^t               ^q or ^. (so)    ^z or ^k

[23 hard] Situation:  A very clueful user just had a program crash in a subdirectory, 

          but isn't sure which one.  She wishes to remove the core file from the crash, 

          along with any earlier core files that may have accumulated, without having 

          to go looking for them.  This particular version of Unix does not make 

          "core.program" files. She should... 

[a] ls -R | awk '/core/ {print "rm -rf "$0}' | sh

[b] find . -name core -type f -exec ls -l '{}' ';' -exec rm -if '{}' ';'

[c] rm -rf core */core */*/core */*/*/core */*/*/*/core */*/*/*/*/core

[d] rm -i `find . -print | grep core`

[e] find . -name core -exec echo -n rm' ' -print | sh -x

[24 hard] Situation:  A Unix guru with a *warped* sense of humor has just written a 

          program to (1) develop a BNF for arbitrary input text, and (2) dump the 

          resulting parser. Likely program names include: 

[a] dad, dd, develop+dump.

[b] buffalo, ee, yay.

[c] bnf, nyacc, yadd.

[d] bar, foo, qux.

[e] dump, mkparser, parse.

[25 hard] Situation:  A very clueful user wishes to catenate the top lines of 

          every file in the current directory (not subdirectories) to standout 

          output. She uses... 

[a] { for f in `find -type f -print` ; do head -1 $f ; done ; }

[b] head -1 *

[c] cat `head -1 *`

[d] { for f in .* * ; do if [ -f $f ]  ; then head -1 $f ; fi ; done ; }

[e] head -1 `ls -dF .* * | grep -v /`

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