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SL.NO Questions Choice A Choice B Choice C Choice D

1 Unix is a _________________ Operating System Single User ans)Multi User Multi

Processes Multi Thread

2 Multiple users can run separate _________________ Jobs Threads ans)ProcessesCommands

3 What is multi tasking System? Multiple users running multiple tasks ans)Single

user running multiple tasks Multiple users running single task Single user running

multiple commands

4 UNIX Commands performs ____________________ ans)Only one function

Multiple functions Two functions None of the above

5 ______________________ provides many tools to perform various tasks Kernel

Command ans)Shell Applications

6 _____________________________ used to perform pattern matching Shell Kernel

Special Characters ans)Meta Characters

7 _________________________ used to write small programs to control Unix

functionalities. Shell Commands ans)Shell Script Filters C Language

8 "_______________ refers to operating system in general, but was based on Unix."

SVID XPG ans)POSIX IEEE

9 ________________________ is the unification of two standards POSIX ans)SUSV3

SVID XPG

10 POSIX 2 deals with _______________________ and

_______________________. ans)Shell & Utilities Shell & Commands Kernel & Shell

Filters & pipes

11 _________________________ interacts directly with system hardware. Shell

Commands ans)Kernel Applications

12 ______________________ provides interface for the user. Kernel ans)Shell

Commands Utilities

13 Unix designed as per _________________________ architecture. Client/Server

Architecture File Architecture Module Architecture ans)Layard Architecture

14 Applications use ___________________ to communicate with kernel. ans)System

Calles C Programs Shell Script Shell

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15 Shell is a ___________________________________. ans)Command Interpreter

Interface between Kernel and Hardware. Interface between user and applications.

Command Compiler.

16 The __________________ is the core of the operating system. Shell ans)KernelCommands Script

17 _____________________________ is loaded into memory when system is

booted. ans)Kernel Shell Commands Script

18 _______________________ is the interface between user and kernel Script

programs ans)Shell C programs System Calls

19 Kernel manages ____________________________ Hardware Resources Shell &

Shell Script ans)System Resources User Resources

20 _________________________ is the program?s gateway to the computer?s

resources. Shell Applications ans)Kernel System Calls

21 _________________________ & ____________________________ are two

types or kernels Single user & Multi user ans)Monolithic & Micro Multi task & Multi

user Micro & Macro

22 _______________________ kernel runs every service in the kernel space.

ans)Monolithic kernel Micro kernel Exo Kernel Macro kernel

23 Micro kernel runs all the services as a daemon in the _________________ Kernel

Space System Space Memory Space ans)User Space

24 In _____________________________ kernel there is no context switching Micro

ans)Monolithic Exo Macro

25 "___________________________ kernel able to decide what do next, if problem

accurse in any of the running service." ans)Micro Monolithic Exo Macro

26 First time UNIX operating system was developed to run on a ____________. 8

bit computer architecture ans)16 bit computer architecture 32 bit computer

architecture 64 bit computer architecture

27 32-bit UNIX platforms use the _________________ programming model. IP16

IP32 ILP16 ans)ILP32

28 ILP32 stands for ____________________________________________. "ans)32

bit Integer, Long & Pointer " 32 bit Integrated Long & Pointer 32 bit Intelligent Long

& Pointer 32 bit Inter Long & Pointer

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29 Sing Unix Specification Version 2 provides enhanced support for

_______________ 16 bit Unix 32 bit Unix ans)64 bit Unix 8 bit Unix

30 LLP64 also known as 8/8/8 ans)'4/4/8 4/8/8 4/8/4

31 __________________ is the process of starting up a computer. Boot LoadingBoot Record ans)Boot Strapping Booting

32 "Bootstrapping, also known as___________________________" Quick boot

ans)Cold boot Hot boot Fast boot

33 Most Unix systems implement a ________________ loading process. One stage

ans)Two stage Three stage Four stage

34 The kernel probes the bus to locate the ____________________ and initializes.

Memory IO ans)Devices Processor

35 "The kernel identifies the _____________,_________________ and

_______________ devices and then starts programs to schedule processes."

"ans)root, swap, and dump" "root, tmp and usr" "root, boot and dump" "root, boot

and tmp"

36 __________________ manages the physical memory by moving process from

physical memory to swap space when more physical memory is needed. Sched

daemon ans)Swap daemon Init daemon Process daemon

37 The last step in bootstrapping the kernel starts

the____________________process. ans)/etc/init /etc/sched /etc/swap /etc/kernel

38 The init process runs as __________________ and always remains in the

background. Process 0 Process -1 ans)Process 1 Process 2

39 Single user mode shell is always __________________________ Bash Csh ksh

ans)sh

40 Single user mode shell runs as __________________________ Admin user

ans)Root user Super user Log user

41 Single user mode only __________________________ partition is mounted .

boot usr ans)root tmp

42 Set of initialization processes is defined in the________________file.

/etc/profile /etc/init /etc/boot ans)/etc/inittab

43 For every user ___________________________ script will be executed.

/etc/inittab ans)/etc/profile /etc/login /etc/init

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44 Various memory handlers run as ___________________________ . Process 0

Process -1 Process 1 Process 2

45 ____________________ can be used to set priority for real-time processes.

ans)Scheduler Swapper Timer Page daemon46 Text and binary files are ____________________. ans)Regular files Device files

Special files Directory files

47 The directory file contains _______________________ and

___________________________. File names & File Sizes ans)File names & Inode

Numbers File names & Address File names & Permissions

48 _____________________ files are used to perform operations on hardware

resources. Executable files Special files ans)Device files Driver files

49 ____________________ directory contains all device files. /etc /etc/dev /root/bin

ans)/dev

50 Lp0 a device file used to access _______________________. Floppy Cdrom

ans)Printer Tap drive

51 __________________ option of ls command used to view file inode no. ?l -o ?a

ans)?i

52 Any file's attribute information is stored in which structure on disk ans)Inode

Data blocks File blocks Directory file

53 If two files on same partition point to the same inode structure they are called

Soft links ans)Hard links Alias Special files

54 Which of the following umask settings allow execute permission to be set by

default on regular files 222 111 000 ans)None of the given choices

55 "If a file with execute permissions set, but with unknown file format is executed"

ans)The file is passed to /bin/sh The system returns an error The current shell will

try to execute it None of the above

56 "find / -name '*' , this command will" List files named * in all subdirectories

ans)List all files in all subdirectories starting from / List a file named * in / directory

List all files in / directory only excluding subdirectories

57 _______________________ command creates an empty file if file not exist. Cat

ans)Touch Ed Read

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58 ________________ option of rmdir command used to remove directory with all

subdirectories ?b ?o ans)?p ?t

59 ___________________ command used to identify file type. Type ans)File Finfo

Info60 Which of the following commands can be to change default permissions for files

and directories at the time of creation Chmod Chwon ans)Umask Chper

61 The tar command is used for Creating and writing tape archives Deleting files

Undeleting files Update modification time stamp on files

62 Which of the following commands will allow the user to search contents of a file

for a particular pattern Touch ans)grep find ls

63 sed is a command typically used for Perform complex calculations Perform FIFO

based non-blocking I/O ans)Modify/print selective contents of a file None of the

above

64 Deleting a soft-link Deletes the destination file Deletes both the softlink and the

destination file ans)Deletes just the softlink A backup of the destination is

automatically created

65 Creating hardlinks pointing across partitions is allowed only to root user Can be

done by all users The effects are unspecified ans)Is impossible to create such links

66 The command sequence ?chmod 4777 a.out;chown root:root a.out? will produce

a.out with suid bit set and ownership set to root ans)a.out with ownership set to

root but suid bit reset This sequence is not allowed a.out file with suid bit set but the

ownership set to the original user.

67 Which of the following is not a valid file type on Linux Socket Softlink ans)Door

FIFO

68 Which of the following is not a file-type on unix ans)Hard link Soft link Socket

Character device

69 Executing cat /etc/password >> /dev/hda1 as superuser will Write data into a file

called /dev/hda1 ans)Will write data to the physical device hda1 Create a temporary

file /dev/hda1 and write data to it None of the above

70 __________________ command used to remove directory with allits sub

directories and files ans)Rm -r rm rm -i rmdir -p

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71 _______________allows fast file system recovery. Ext2 ans)Journaling Caching

Sysfs

72 ________________ can be used to obtain information about the system and to

change certain kernel parameters at runtime using sysctl command. Ext3 Sysfs Isofsans)Procfs

73 ________________________ file system used for CD-ROM. Ext2 Ext3 ans)Isofs

Procfs

74 _______________ is use to exporting kernel objects so that end user can use it

easily. ans)Sysfs Ext3 Isofs Procfs

75 _________________________ file system has jurnaling capabilities. Ext2

ans)Ext3 Isofs Procfs

76 _________________ & ____________________ are the two types of device files

ans)Character special & block special Character special & Byte special Byte special &

bit special Input & output

77 __________________________ is an example for character special file. Hard disk

CD-ROM ans)Terminal Memory

78 __________________________ is an example for block special file. Virtual

Terminal ans)CD-ROM Terminal Serial modem

79 All device files are stored in ____________________ directory. /etc /bin ans)/dev

/usr

80 ____________ allows transparent communication between user space

applications and computer hardware. ans)Device files Script files Special files Regular

files

81 If superuser executed ?mount /dev/sda1 /etc? and /dev/sda1 contains a non-unix

file system ans)The system will no longer perform correctly This operation will not

be allowed The mount will succeed and no effects will occur on the system The

behavior is undefined

82 "During theboot process, file systems listed in____________are automatically

mounted" /etc/mount ans)/etc/fstab /etc/inittab /etc/boot

83 "________________________ is a directory (which should exist), on which to

mount the file system." Root Boot ans)Mount-point Partition

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84 ___________________ command used to mount file system read only. Mount ?a

Mount ?v Mount ?f ans)Mount ?r

85 _______________ Force the mount of an unclean file system (dangerous). Mount

?a Mount ?v ans)Mount-f Mount ?r86 "To increase the response time and throughput, the kernel minimizes the

frequency of disk access by keeping a pool of internal data buffer called " Pooling

Spooling ans)Buffer cache Swapping

87 Buffer cache contains the data in recently used _________________ Files

ans)Disk block Directory Data block

88 kernel identifies the buffer content by examing _________________ and

___________________. Memory array & block header Block address & memory

address ans)Device num & block num Non of the above

89 A buffer consist of _____________________ & ___________________________

Memory & blocks Device list & block List Header & body ans)Memory Array & Buffer

Header

90 Buffer header contains Pointer ans)status data none of the above

91 ______________ is about how your Operating System allows you to manage a

large number of open files. File Handling ans)IO Event Handling File Management IO

Management

92 Traditional Unix systems provide the_______ and _____________system calls.

ans)Select(2) & poll(2) Get(2) & put(2) Read() & write() None of the above

93 POXIS provides _________________________ interfaces AEO ADO ADD ans)AIO

94 FD stands for Fixed Data ans)File Descriptor Fast Data Full Data

95 File Descripter is a small non-negative number returned by ______________

function. Close() Read() ans)Open() Write()

96 The fd is an index into the _________________ file table Memory ans)Process

Inod Non of the above

97 Fd for standard error __________________________. 0 1 2 Non of the above

98 Fd for standard input __________________________. ans)0 1 2 Non of the

above

99 Fd for standard output __________________________. 0 ans)1 2 Non of the

above

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100 "Fd value used as _____________________________ in read(),write() &

close()." Second argument ans)First argument Last argument Return value

101 "While using open system call if an error occurs in trying to open the file, a

_____ is returned." 4 3 ans)Negative number 0102 "While using create The named file is created as an empty file and opened for

writing, __________________________ is returned." ans)Open file identifier

Negative number 0 Non of the above

103 _____________________________ system call used to delete a file Delete

Erase ans)Unlink None of the above

104 _______________________________ system call used to move position on

next read / write Goto Move Jump ans)Lseek

105 _______________ value is used to specify read/write mode in open system call.

0 ans)1 2 3

106 The kernel provides random access by calling function ___________________.

Random ans)Lseek Fetch Read

107 The signature of the lseek system call "int lseek(int fd, long offset, int origin)"

"float lseek(int fd, long offset, long origin)" "long lseek(long fd, long offset, long

origin)" "ans)long lseek(int fd, long offset, int origin)"

108 To read from the current position ___________ value can be specified as origin.

0 ans)1 2 3

109 To read from the beginning ___________ value can be specified as origin. ans)0

1 2 3

110 To read from the end ___________ value can be specified as origin. 0 1 ans)2 3

111 Which of the following tasks is not performed by the shell? ans)Disk Quota

Mangement Command Execution Process Creation None of the above

112 The shell prints the Prompt String on which descriptor STDIN STDOUT

ans)STDERR STDOUT + STDERR

113 Which of the following is not an IPC mechanism Shared Memory Unix Domain

Socket Named Pipes ans)Memory mapping

114 Which of the following IPC mechanisms can communicate file descriptors to

other processes Shared Memory ans)Unix Domain Socket FIFO Message Queues

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115 Which of the following time stamps need not exist for a file on traditional unix

file system Access Time Modification Time ans)Creation Time Change Time

116 "Which of the following is not a system call, but is a library function" brk open

creat ans)malloc117 Which of the following is the first process on a Unix system ans)swapper

sendmail ftp init

118 Which one of the following IPC mechanisms can communicate file descriptors to

other processes Shared Memory Unix Domain Socket Message Queues FIFO

119 "For a real time signal, if a signal arrives while its previous instance is being

serviced" The current instance is lost The service routine is invoked again ans)It is

queued for service A second copy of the process is started.

120 Which of the following signals can not be handled or ignored HUP ans)KILL FPE

QUIT

121 If a program executing in background attempts to read from STDIN It is

terminated ans)It's execution is suspended STDIN is made available to it None of the

above.

122 Which of the following mechanisms is used to provide virtual memory (swap) on

new Unix systems Swapping ans)Paging Shared Memory None of the above

123 Which system call is used to duplicate one file descriptor to another known file

descriptor number fcntl dup ans)dup2 reopen

124 "Which of the following redirection mechanisms causes shell to buffer data from

STDIN (cmd is the command and >, < , >>,

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128 In a multi-threaded process if one of the threads blocks in a system call other

threads are ans)Suspended Continue execution Process is terminated The system

does not block threads

129 Which of the following mechanisms is used to get lock on data in a multi-threaded program ans)mutex shared memory signals pipes

130 How many number of unique user ids does a traditional unix system support

ans)65536 256 2^24 2^32

131 After fork() (In a non-BSD system) if the child does modifies the parent's data

ans)The system copies all memory segments before continuing the child's execution

The child is suspended The parent is suspended till the child exits None of the above

132 After exec the file descriptors of the parent are available to the child if The

KEEP_ON_EXEC flag is set ans)The CLOSE_ON_EXEC flag is not set The file

descriptors are duplicated before exec exec is passed arguments to keep the file

descriptors open.

133 To feed standard output of one command to standard input of another in a

single shell session IO redirection can be used Named pipes can be used ans)The

pipe operator provided by the shell can be used It can not be done

134 The return value from a successful exec system call is 0 -1 255 ans)None from

the given choices

135 Which is the default executable format supported by new unix systems a.out

exe com ans)ELF

136 The ldd command can be used to ans)List shared library dependencies of an

executable file Load a library to memory Link a dynamic library to a running program

Link multiple object files together

137 The executable segment of a program in traditional unix terminology is called

Extra segment Code segment ans)Text Segment Stack segment

138 If the /etc/passwd file's password entry is indicated as a single x then the

passwords are stored in ans)/etc/shadow /etc/enpasswwd /etc/.passwd The account

is disabled

139 Messages are registered to the standard syslog daemon using which mechanism

ans)Unix Domain Socket FIFO Message Queues Mutex

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140 Message queue mechanism is implemented in which layer of the OS ans)Kernel

Wrapper Library Separate driver None of the above

141 A user can change the default log-in shell using chmod ans)chsh rmsh tchsh

142 The Control+C character sequence generates which signal ans)SIGINT SIGTERMSIGQUIT SIGPIPE

143 A driver on Linux is called a Daemon Driver ans)Module None of the above

144 During exwcution of a system call Program execution continues in user mode

ans)Program is switched to kernel mode to service the system call Normal users can

not use system calls None of the above

145 During bootup init process reads this file for configuration settings initrc init.conf

ans)inittab init.d

146 "After calling exit, till the point when the parent reads back the exit status the

process state is" ans)Zombie Suspended Sleeping in interruptible sleep Waiting for

Event

147 "When a process exits, all of its child processes are first sent" SIGINT SIGCONT

ans)SIGHUP SIGTERM

148 When a child's parent exits before the child the child process is inherited by

swapper kernel ans)init a special garbage collection process

149 Multiple functions registered with atexit are ans)Called in a LIFO fashion Called

in a FIFO fashion Are executed in parallel atexit can register only one function

150 When data is piped into a while loop (in a shell script) the while loop is

ans)Executed in a separate shell instance Executed in the same shell as the script It

is not possible to pipe data into while loops None of the above

151 A process with priority +19 executes (On Linux) with low priority With highest

possible priority ans)With lowest possible priority With RealTime priority

152 When a process exits the message queues created are Automatically destroyed

ans)Remain on the system till explicitly removed or system reboot Process exit is not

allowed till all associated message queues are removed The behavior is undefined

153 If one process passes pointer to a shared memory segment to another process

The other process can access the shared memory ans)Such a pointer can not be

passed Shared memory is accessible by all processes None of the above

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154 On Linux if a mount is attempted on a directory on which some other device is

already mounted The command fails The system unmounts the first device then

mounts the new device ans)The mount succeeds on top of the old mount The

behavior is undefined155 The dmesg command Shows user login logoff attempts Shows the syslog file for

info messages ans)Shows the kernel log messages Shows the daemon log messages

156 wtmp and utmp are files containig Temporary system data ans)User login-logout

and system restart event log The user's command execution log The user's su and

sudo attempts

157 The unlink system call on a file ans)Removes directory entry and then

decrements inode link count Decrements inode link count by one and then removes

the directory entry "Removes only the directory entry, the links count is

decremented by a special process" None of the above

158 If a file open by a process is unlinked by another The operation is not allowed

The process that is trying to unlink the file is suspended ans)The operation is carried

out successfully but file contents are available to original process till file is closed

Behavior is undefined

159 The area of a unix style partition that holds integrity checking information about

data block allocations is called superblock ans)bitmap block inode block Integrity

Block

160 Which of the following commands allows definition and assignment of

environment variables under bash env ans)export environ setenviron

161 The $ variables in a shell script context designates The runtime of the script

Number of command line arguments ans)PID of the shell running the script The exit

status of the shell script

162 If a process receives SIGCHLD and has not made provisions to handle it It is

terminated ans)Execution continues Behaviour is undefined None of the above

163 The alarm system call schedules delivery of SIGALRM to process after Scheduled

time has elapsed in real time ans)Scheduled time has elapsed as process run time

Scheduled time has elapsed while executing system calls None of the above

164 Which of the following system calls can be used to detect change in last status

of an file descriptor (edge triggered behavior) select poll ans)epoll ipoll

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165 If a write is going to block on a file descriptor marked as Non-Blocking ans)The

call returns an error status indicating as such The call blocks The write is done to a

temporary buffer and then transfered to the actual file descriptor The behavior is

undefined166 The command ?mknod myfifo b 4 16? will ans)Will create a block device if user

is root Will create a FIFO if user is not root Will Fail if user is not root None of the

above

167 While executing a command the shell Executes it in the same process ans)Starts

a subshell to execute it Loads a special program to take care of the execution None

of the above

168 When a user process's stack overflows the kernel Immediately terminates the

process ans)Allocates extra stack for the process transparently Sends a SIGSEGV to

the process The system crashes.

169 "Under Linux, after a fork if the child does not modify the parent's data till exit"

"ans)Actual memory copy does not get carried out, only a separate process is

created" A separate copy of all segments is created Only Data Segment is copied

and Text is always shared The parent is suspended till child exits

170 "Which of the following is true for vfork system call, when compared with fork"

The child and parent run simultaneously as threads ans)The parent is blocked till the

child exits or calls exec The stack segments for both processes are shared vfork and

fork are same

171 Which of the following is not a valid run-level S 0 ans)12 1

172 "On Linux, initrd is a file" containing root file-system required during bootup

Contains only scripts to be executed during bootup ans)Contains root-file system and

drivers required to be preloaded during bootup None of the above

173 Which of the following identifiers associated with a process decide its privilege

level uid suid ans)euid gid

174 Which of the following mechanisms can be used for network communication

unix domain sockets ans)ethernet link level protocol Shared Memory pipes

175 Which of the following IPC mechanisms allows file descriptors to be passed

between processes ans)unix domain sockets message queues Shared Memory It can

not be done

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176 electricfence is a Firewall for Unix ans)Library wrapper around malloc to detect

memory leaks at runtime A physical security implemetation for intrusion detection

None of the above

177 Which Lock will actually preventread()s andwrite()s to file. ans)Mandatorysystems Advisory system Auto Lock None of the above

178 Advisory read locks also referred to as external locks exclusive locks ans)shared

locks None of the above

179 POSIX:XSI Extension define time resolutions of nanoseconds ans)microseconds

seconds minutes

180 POSIX:TMR Extension define time resolutions of ans)nanoseconds microseconds

seconds minutes

181 The _______________ spesifies thread safe alternatives POSIX:XSI POSIX:TMR

PSIX:TSM ans)POSIX:TSF

182 A clock is a counter that increments at fixed intervals called ans)clock resolution

clock timer clock seconds Non of the above

183 The function used to set clock time in POSIX clock_writetime clock_puttime

ans)clock_settime clock_time

184 The function used to get time in POSIX ans)clock_gettime clock_readtime

clock_time None of the above

185 Which one has interval time POSIX:TMI ans)POSIX:XSI POSIX:INT POSIX:TSF

186 Which POSIX function used to create a thread ans)pthread_create

thread_create pthread_new thread+new

187 Which POSIX function used to wait for a thread pthread_pause

ans)pthread_wait thread_wait thread_stop

188 Which POSIX functionused to set thread to realease resources pthread_release

pthread_close pthread_exit ans)pthread_detach

189 Which PSIX function used to start a thread pthread_start pthread_resume

pthread_wait None of the above

190 Which function does not have to be thread safe ans)strerror strread strwrite

strerror_r

191 ULT usually link to a special library in which each library function is enclosed by

a brace brackets ans)jacket Non of the above

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192 User Threads runs top of ans)kernal threads shell threads application threads

Non of the above

193 Which one schedules kernal-level threads Shell Kernal it self ans)Operating

System User194 Which parameter is apointer to the attribute object in threads ans)attr pram var

Non of the above

195 A thead has a __________________ whose location and seze are user settable

attribute ans)stack functions variable

196 A ___________________ is a special variable that can be either in the lovked

state or the unlocked state condition variable read-write locks sync variable

ans)Mutex

197 A program must always intialize _________________ valraible before using

them in mutex pthread_mutex_a ans)pthread_mutex_t pthread_mutex_p

pthread_mutex_s

198 The _____________________ function blocks until the mutex is available

ans)pthread_mutex_lock pthread_mutex_trylock pthread_lock

pthread_mutex_trylock

199 A __________________ is software notification to a process of an event.

interrupt lock ipc ans)signal

200 Every signal has a symbolic name starting with ___________ SIGNAL SGL

ans)SIG SNL

201 Which command used to generate signals signal ipc gen ans)kill

202 Which signal used to stop background process attempting to read SIGREAD

ans)SIGTTIN SIGRED SIGIN

203 If kill command unsuccessful because of invalid signal it returns

________________ error EPERM ESRCH ans)EINVAL ERROR

204 The ___________________ function allows to examine the action associated

with a specific signal ans)sigaction sigexam siganalyse signotify

205 "Kernel maintains free space of the swap device in an in-core table, called "

page Block ans)map section

206 The kernel must gather the ____________ of data at primary memory to be

swapped out ans)page addresses map address block address Non of the above

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207 In ___________________________ not all page of process resides in memory

Swaping ans)Demand Paging Paging Memory

208 "In Demand Paging when a process accesses a page that is not part of its

working set, it incurs a " ans)page fault. page error an exception Non of the above209 ___________________ contains the physical address of page swap table page

entry swap entry ans)Page Table

210 _____________________ contains swap device no and block number swap

table page entry ans)Disk Block Discriptor Page Table

211 Which command displays information about ipc respirces ans)ipcs ipc ipcinfo

ipcset

212 Which function returns the semaphore identifier associated with the key

parameter seget ans)semget sget get

213 Each element of a semaphore set must be intialized with _______________

ans)semctl semid semvar semtem

214 Which function atomically performs a user-defined collection of semaphore

operations semctl semid ans)semop semnum

215 ___________________ allows processes to read and write from the same

memory segment register ans)shared memory buffers Non of the above

216 Which header file defins the data structures for shared memory ans)sys/shm.h

sys/share.h sys/mem.h sys/mstrea.h

217 Which function used to attach the shared memory segment shatach shmatach

ans)shmat shmem

218 Which function provides a variety of control operations on the shared memory

segment shctl sctl shmemctl ans)shmctl

219 The ________ is a ipc machanism that allows a process to send receive

messages Shared Memory semaphor ans)Message Queues Non of the above

220 Which function returns the message queue identifier ans)mesget msgread mget

msget

221 A_______________ is a process that has completed execution but has not been

waited for by its parent. thread ipc ans)zombie Non of the above

222 Which function used to create a TCP socket bound to port ans)u_open u_create

u_port u_accept

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223 Which function waits for connection request on fd u_open u_create u_port

ans)u_accept

224 Which function intiates a connection to server u_open u_create ans)U_connect

u_accept225 A __________________ is a logical pathway for information ans)comunication

chanel commnucation path communication route Non of the above

226 Which api provides connection-oriented communication CIUI ans)UICI UCCI

UICC

227 Which function creates a communication endpoint and returns a file descriptor.

ans)socket bind accept connect

228 A successful socket return a nonnegative integer corresponding to a socket

ans)socket file descriptor ip address port no

229 Which function associates endpoint with specific port socket accept connect

ans)bind

230 To use the socket to accept incoming request an application need to call

_______ function socket accept ans)listen connect

231 The server handles incoming client connections by calling _______________

function socket ans)accept listen connect

232 Which function a client uses to establish a link to the well-known port of the

server socket accept listen ans)connect

233 Which function behaves like inet_addr except that its parameter can be either a

host name or an address ans)name2addr addr2name gethostbyname host2name

234 Which function a parent process can use to block until child's status finishes.

fork ans)wait pause block

235 Which function used to create a copy of current process exec create child

ans)fork

236 Which function used to create a child process that is different form calling

process ans)exec create child fork

237 Which process creation function pass the command line arguments in an explicit

list execv execvp exec ans)execl

238 A __________ is a background process that normally runs indefinitely thread

child process daemon Non of the above

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239 Which library function used to get group process id getpid getpd getppid

ans)getpgid

240 On many systems the end of file character is Ctrl C ans)Ctrl D Ctrl Z EOF

241 Which function provides a method of monitoring file descriptors from a singleprocess. monitor poll ans)select check

242 Which function organizes the information by file descriptor rather than by type

of condition monitor ans)poll select check

243 ________________________ represents the user home directory / . .. ~

244 Which function returns current pathname of the current working directory

getpath pathconf ans)getpwd pwd

245 Which function used to open a directory open ans)opendir raed readdir

246 The opendir function returns _____________________ ans)DIR type FILE type

int int pointer

247 Which function takes file name and retrieves file status accesss fstat ans)lstate

files

248 Which function accesses a file with an open file descriptor and returns the state

accesss ans)fstat lstate files

249 Which PSIX Macro used to determine pipe or FIFO special files S_ISDIR S_ISSPE

ans)S_ISFIFO S_ISREG

250 Which POSIX Macro used to determin shared memory object S_TYPEISMQ

ans)S_TYPEISSEM S_TYPEISSHM Non of the above

251 __________________ command used to determin the path of an executable file

ans)which where wexec what

252 ______________________ is the simplest ipc machanism. Shared Memory

ans)pipe FIFO Message Queues

253 _____________________________ is a named pipe and appears in the

directory listing. Shared Memory pipe ans)FIFO Message Queues

254 _________________ command or function used to create FIFO create_fifo

ans)mkfifo mk_fifo cfifo

255 ___________________ command used to set terminal IO charactresistic tty ctty

ptty stty

256 How many number of user singals available 1 ans)2 3 0

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257 A process can send a signal to itself with _________________ function

ans)raise signal throw Non of the above

258 Which function causes a SIGALRM raise ans)alaram kill Non of the above

259 A progrm can access system time by calling ____________________ functiontime_t sys_time ans)time stime

260 which function converts the structure returned by localtime to a string ctime

ans)asctime local time

261 which function used to return UTC time utime asctime ans)gmtime localtime

262 The ________ function takes into accout both the time zone and day light

saving time. ans)ctime utime asctime gmtime

263 _________________________ function used to find out own thread ID

pthread_getid ans)pthread_self pthread_id Non of the above

264 Which function used to terminat a thread ans)pthread_kill kill kill -9 Non of the

above

265 Which function used to set its signal mask for a thread pthread_mask pmask

ans)pthread_sigmask pthread_msk

266 ______________________ sychronization always gices preference to writers

Writer Strong Writer Full Writer Non of the above

267 Which function allow a thread to acquire a read-write lock for reading

ans)pthread_rwlock_rdlock pthread_rwlock_wrlock pthread_rwlock Non of the above

268 Which function allow a thread to acquire a read-write lock for writing

pthread_rwlock_rdlock ans)pthread_rwlock_wrlock pthread_wrlock Non of the above

269 Which function implemetns the classic semaphore wait oparation wait

pthread_wait ans)sem_wait Non of the above

270 Which function implements the classic semaphore signalling sem_sig

ans)sem_post post pthread-sig

271 Which function intializes the value of the shared variable. initsh initsm initshared

init

272 Which header file has the POSIX thread functions thread.h posix.h

ans)pthread.h Non of the above

273 The ___________ function establishes the connection between a named

semaphore and a sem_t value sem_create ans)sem_open sem_ns Non of the above

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274 To remove POSIX:XSI ipc resources ____________________ command is used

ipcs ipcremove ans)ipcrm ipcdelete

275 The __________________ command used to start a forground proccess in

background ans)bg fg background forground276 ________________________ creates a one way connection between process

FIFO ans)pipes shared memory massage queue

277 The ______________ function can be used to print a meaningful description of

the error. ans)perror ferror error Non of the above

278 "the _________________ as a special file that can store a limited amount of

data in a first in, first out manner" FIFO shared memory ans)pipe Semaphores

279 The ___________________ command is an alternative to echo command

ans)printf print display Non of the above

280 The _______________ command used to record a user login session in a file

macro read ans)script none of the above

281 Which command is used to display the operating system name os Unix kernel

uname

282 __________________ command is used to display the unix version ans)uname -

r uname -n uname -t kernel

283 __________ command is used to print a file print ptr ans)lpr none of the above

284 The ___________ command is used to display the octal value of the text octal

text_oct oct ans)od

285 The ____________ command is used to view compressed text file contents cat

type ans)zcat print

286 The _____________ command changes a file's group owner cgrp ans)chgrp

change group

287 The ____________ is used to search for a pattern in vi editor \ * ans)() ?

288 The ____________ command is used to extract intermediate result in a pipeline

ans)tee extract exec none of the above

289 The _____________ command is used to extract a column from a text file paste

get ans)cut tar

290 The _______________ variable is used to display number of arguments

specified in command line $0 ans)$# $* $?

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291 Which variable contains current shell process id $* $? ans)$$ $!

292 Which variable contains last background job process id $* $? $$ ans)$!

293 Which command can be used to test various file attributes if file ans)test type

294 Which command is used to debug a shell script program set ans)set -x debug db295 Which command is used to set limits on file size fsize flimit ans)ulimit usize

296 Which command is used to display disk consumption of a specific directory

ans)du ds dd dds

297 The ______________ command is used to perform backup backup ans)cpio zip

gzip

298 Which function is used to create softlink link softlink ans)symlink slink

299 Which function is used to change the file's modification and access time

ans)utime touch stime sftime

300 Which function is used to duplicate a file descriptor dup_fd ans)dup fd dfile