dba important linux commands

5/28/2018 dba important linux commands

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UNIX / Linux: 7 Practical PS Command Examples for Process Monitoring

! S"SI#"L" on "P$IL %&' &(%%

Process is a running instance of a program) Linux

is a multitas*ing operating s!stem' +,ic, means t,at more t,an one process can e acti-e atonce) Use ps command to find out +,at processes are running on !our s!stem)

.,is article explains 7 practical usages of ps command and its options)

.o monitor and control t,e processes' Linux pro-ides lot of commands suc, as ps' *ill'*illall' nice 'renice and top commands)

%) List Currentl! $unning Processes ps 0ef' ps 0aux1

Its a commonl! used example +it, a ps command to list do+n all t,e process +,ic, arecurrentl! running in a mac,ine) .,e follo+ing example s,o+s t,e options of ps command to get

all t,e processes)

2 ps 0ef

root &344% 4 ( 5e%( 6 ((:(:8% 9pdflus,

root &347( 4 ( 5e%( 6 ((:((:&( 9pdflus,

root (88 ;& ( 5e&% 6 ((:((:%% ss,d: root


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In case of ?S@ mac,ines' !ou can use Aps 0auxB +ill gi-e t,e details aout all t,e process ass,o+n ao-e)

2 ps 0aux

&) List t,e Process ased on t,e UI@ and Commands ps 0u' ps 0C1

Use 0u option to displa!s t,e process t,at elongs to a specific username) >,en !ou ,a-emultiple username' separate t,em using a comma) .,e example elo+ displa!s all t,e processt,at are o+ned ! user +++run' or postfix)

2 ps 0f 0u +++run'postfix

UI@ PI@ PPI@ C S.IME .. .IME CM@

postfix 7847 784 ( Mar(= 6 ((:((:(( Dmgr 0l 0t fifo 0u

+++run 78=4 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f

/etc/apac,e&/,ttpd)conf

+++run 78=3 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

+++run 78=7 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

+++run 78=; 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

+++run 78== 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

+++run %((7; 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

+++run %((;& 78=% ( Mar(= 6 ((:((:(( /usr/sin/,ttpd&0prefor* 0f/etc/apac,e&/,ttpd)conf

postfix %4377 784 ( &&:& 6 ((:((:(( pic*up 0l 0t fifo 0u

ften ps is used +it, grep li*e Fps 0aux G grep commandH to get t,e list of process +it, t,e gi-en

command)?ut ps command itself ,as an option to ac,ie-e t,e same) .,e follo+ing example s,o+s t,at allt,e processes +,ic, ,as tatad)pl in its command execution)

2 ps 0f 0C tatad)pl



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root =473 % ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =477 =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =47= =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;( =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;% =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;& =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root %&% =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

Note: >e can create aliasesfor ps command to list processes ased on commands' users orgroups)

) List t,e processes ased on PI@s or PPI@s ps 0p' ps ppid1

Eac, process +ill e assigned +it, t,e uniDue Process I@ PI@1)

>,en !ou launc, some application' it mig,t for* numer of processes and eac, su process+ill ,a-e its o+n PI@) So' eac, process +ill ,a-e its o+n process id and parent processid)

5or all t,e processes t,at a process for*s +ill ,a-e t,e same PPI@ parent process identifier1).,e follo+ing met,od is used to get a list of processes +it, a particular PPI@)

2 ps 0f 00ppid =473


root =477 =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =47= =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;( =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;% =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root =4;& =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

root %&% =473 ( Mar(= 6 ((:((:(( /opt/tata/perl/in/perl /opt/tata/in/tatad)pl

.,e follo+ing example is to list t,e processes +,ic, ,as gi-en PI@)

2 ps 0f 0p &4((='7&4;'&8&3


root &8&3 8 ( Mar(= 6 ((:((:(( 9reiserfs/(

root 7&4; % ( Mar(= 6 ((:((:(( /usr/sin/nscd
http://www.thegeekstuff.com/2010/04/unix-bash-alias-examples/http://www.thegeekstuff.com/2010/04/unix-bash-alias-examples/


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postfix &4((= 784 ( ((:(& 6 ((:((:(( pic*up 0l 0t fifo 0u

8) List Processes in a Jierarc,! ps forest1

.,e example elo+ displa! t,e process Id and commands in a ,ierarc,!) forest is an argumentto ps command +,ic, displa!s "SCII art of process tree) 5rom t,is tree' +e can identif! +,ic, is

t,e parent process and t,e c,ild processes it for*ed in a recursi-e manner)

2 ps 0e 0o pid'args 00forest

83; K ss,d: root


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3) List all t,reads for a particular process ps 0L1

ou can get a list of t,reads for t,e processes) >,en a process ,angs' +e mig,t need toidentif! t,e list of t,reads running for a particular process as s,o+n elo+)

2 ps 0C a-a 0L 0o pid'tid'pcpu'state'nl+p'args

PI@ .I@ QCPU S NL>P CMM"N@

%3==& %3==& ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %3== ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %3==8 ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3




%3==& %3==; ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %3=== ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %7((( ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %7((% ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3


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%3==& %7((& ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %7(( ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug

0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %7(&8 ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %474 ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

%3==& %4748 ()( S %4 ))/re/in/a-a 0@a-a)ext)dirs))/re/li/ext:))/li:))/autoli 0Xdeug

0Xnoagent 0@a-a)compilerNNE0Xrund+p:transportdtsoc*et'ser-er!'suspendn'address4((3

0L option is used to displa! t,e list of t,reads for a process +,ic, ,as t,e command gi-en) "ndit also displa!s nl+p' +,ic, represents numer of lig,t +eig,t processes) In t,e ao-e example'a total of %4 a-a t,reads are running)

7) 5inding memor! Lea* ps sort pmem1

" memor! lea*' tec,nicall!' is an e-er0increasing usage of memor! ! an application)

>it, common des*top applications' t,is ma! go unnoticed' ecause a process t!picall! freesan! memor! it ,as used +,en !ou close t,e application)

Jo+e-er' In t,e client/ser-er model' memor! lea*age is a serious issue' ecause applicationsare expected to e a-ailale &8R7) "pplications must not continue to increase t,eir memor!usage indefinitel!' ecause t,is can cause serious issues) .o monitor suc, memor! lea*s' +ecan use t,e follo+ing commands)

2 ps aux 00sort pmem

USE$ PI@ QCPU QMEM ST $SS .. S.". S."$. .IME CMM"N@root % ()( ()( %4&( 4(; 6 S &((4 %:&7 init

inst %(= ()( ()8 88(; (8; 6 S &((4 %:44 agnt idle1

inst &=%= ()( ()8 844;( 73; 6 S &((4 &(:(& agnt idle1

inst &84=8 ()( ()8 84(3; 3=3( 6 S &((4 %4:84 agnt idle1


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root &7384 ()( %8)8 %&%&;; %%;=73 6 S &((4 :(% /.as*Ser-er/in/)/+rapper0linux0x;30&

In t,e ao-e ps command' sort option outputs t,e ,ig,est QMEM at ottom) ust note do+nt,e PI@ for t,e ,ig,est QMEM usage) .,en use ps command to -ie+ all t,e details aout t,is

process id' and monitor t,e c,ange o-er time) ou ,ad to manuall! repeat ir or put it as a cronto a file)

2 ps e- 00pid&7384

PI@ .. S.". .IME M"5L .$S @$S $SS QMEM CMM"N@

&7384 6 S :(% ( &4 %&%&3& %%;=73 %8)8 /.as*Ser-er/in/)/+rapper0linux0x;30&

2 ps e- 00pid&7384

PI@ .. S.". .IME M"5L .$S @$S $SS QMEM CMM"N@

&7384 6 S :(% ( &4 %&%&3& %%;=73 %8)8 /.as*Ser-er/in/)/+rapper0linux0x;30&

Note: In t,e ao-e output' if $SS resident set siVe' in #?1 increases o-er time so +ouldQMEM1' it ma! indicate a memor! lea* in t,e application)

S+itc,e of ps : SIMPLE P$CESS SELEC.IN

S+itc, @escription

0" select all processes

0N negate selection

0a select all +it, a tt! except session leaders

0d select all' ut omit session leaders

0e select all processes

. select all processes on t,is terminal

a select all processes on a terminal' including t,ose of ot,erusers

g reall! all' e-en group leaders does not,ing +/o SunSsettings1

r restrict output to running processes

x select processes +it,out controlling tt!s


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00deselect

negate selection

P$CESS SELEC.IN ? LIS.

S+itc, @escription

0C select ! command name

0W select ! $WI@ supports names1

0U select ! $UI@ supports names1

0g select ! session leader $ ! group name

0p select ! PI@

0s select processes elonging to t,e sessionsgi-en

0t select ! tt!

0u select ! effecti-e user I@ supports names1

U select processes for specified users

p select ! process I@

t select ! tt!

00Wroup

select ! real group name or I@

00User select ! real user name or I@

00group select ! effecti-e group name or I@

00pid select ! process I@

00sid select ! session I@

00tt! select ! terminal

00user select ! effecti-e user name or I@

0%& implied 00sid

%& implied 00pid

U.PU. 5$M". CN.$L

S+itc, @escription

0 is preloaded 0o


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0c different sc,eduler info for 0l option

0f does full listing

0 os format

0l long format0o user0defined format

0! do not s,o+ flagsY s,o+ rss in place ofaddr

is preloaded o o-erloaded1

X old Linux i;3 register format

o control format

l displa! long format

o specif! user0defined format

s displa! signal format

u displa! user0oriented format

- displa! -irtual memor! format

00formatuser0defined format

U.PU. M@I5IE$S

S+itc, @escription

0J s,o+ process ,ierarc,! forest1

0m s,o+ all t,reads

0n set namelist file

0+ +ide output

C use ra+ CPU time for QCPU instead of deca!ing a-erage

N specif! namelist file

sorting order o-erloaded1

S include some dead c,ild process data as a sum +it, t,eparent1

c true command name

e s,o+ en-ironment after t,e command


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f "SCII0art process ,ierarc,! forest1

, do not print ,eader lines repeat ,eader lines in ?S@personalit!1

m all t,reads

n numeric output for >CJ"N and USE$

+ +ide output

00cols set screen +idt,

00columns set screen +idt,

00cumulati-e

include some dead c,ild process data as a sum +it, t,eparent1

00forest "SCII art process tree

00,tml J.ML escaped output

00,eaders repeat ,eader lines

00no0,eaders

print no ,eader line at all

00lines set screen ,eig,t

00nul unustified output +it, NULs

00null unustified output +it, NULs

00ro+s set screen ,eig,t

00sort specif! sorting order

00+idt, set screen +idt,

00Vero unustified output +it, NULs

IN5$M".IN

S+itc, @escription

0 print -ersion

L list all formatspecifiers

s,o+ -ersion info

00,elp print ,elp message

00info print deugging info


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00-ersion

print -ersion

?SLE.E

S+itc,

@escription

" increase t,e argument space @ecUnix1

M use alternate core tr! 0n or N instead1

> get s+ap info from ))) not /de-/drum tr! 0n or Ninstead1

* use /-mcore as c0dumpfile tr! 0n or N instead1

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ))

%( Linux @U Command Examples 5iles and 5olders @is* Usage SiVe1

! JIM"NSJU "$$" on UNE &7' &(%&

@u stands for @is* Usage)

Linux du command is used for summariVing t,e dis* usage in terms of file siVe) It can e used+it, folders to get t,e total dis* usage) .,is article pro-ides some examples on ,o+ to use ducommand effecti-el!)

"ll t,e du examples s,o+n ,ere are executed on a director! containing t,e follo+ing contents:

2 ls

linux#ernel red,at testfile)txt uuntu

%) " asic example

2 du 0a

( )/red,at/r,7

8 )/red,at

8 )/testfile)txt

( )/linux#ernel


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( )/uuntu/u%(

8 )/uuntu

%3 )

I ,a-e used t,e 0a flag in t,e example ao-e to s,o+ t,e dis* usage of all t,e files anddirectories) Its ecause if 0a is not used t,en onl! directories t,at are occup!ing some dis* arelisted) 5or example :

2 du

8 )/red,at

8 )/uuntu

%3 )

So' no+ +e get a asic idea aout ,o+ to use du command ut as +it, me' an!one +ould find it,ard to understand +,at t,ose numers in t,e output mean66Lets mo-e on to next examples and t,e clouds +ill clear off)

&) @ispla! output in ,uman readale form using 0,

2 du 0a,

( )/red,at/r,7

8)(# )/red,at

8)(# )/testfile)txt

( )/linux#ernel

( )/uuntu/u%(

8)(# )/uuntu

%3# )

So +e see t,at in t,e ao-e example' I used t,e 0, flag along +it, t,e 0a flag) .,e 0, flag isused to get t,e output in t,e ,uman readale format) "s !ou can see t,at ao-e output is more

eas! to understand as dis* usage is listed in terms of A#B)

) @ispla! grand total in t,e output using 0c

.,e example t,at I am using ,as a small director! structure) ne could easil! calculate t,e totaldis* usage of t,e director! ! calculating manuall!) ?ut' in real time scenario manual calculationis not practical) So' t,ere exists a flag t,roug, +,ic, one can get t,e total usage in t,e output)

2 du 0a,c


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( )/red,at/r,7

8)(# )/red,at

8)(# )/testfile)txt

( )/linux#ernel

( )/uuntu/u%(

8)(# )/uuntu

%3# )

%3# total

So +e see t,at t,roug, t,e 0c flag' one can get t,e total usage in t,e output)

8) @ispla! onl! t,e total count using 0sIf !ou +is, to fetc, onl! t,e total siVe in form of a summar!' use t,e 0s flag)

2 du 0s,

7)W )

So +e see t,at onl! t,e total siVe +as displa!ed in t,e output ao-e)

4) 5eed input files from stdin using Afiles(0from0B

If t,ere arises a situation +,erein !ou +ant to pro-ide AduB input on t,e go' t,en t,is is possile

t,roug, t,e Afiles(0fromB flag)

2 du 0a, 00files(0from0

cop!% cop!

file% file

,ello>orld%,ello>orld

[C

2

Note t,at +e passed -alue as A0B to t,e flag Afiles(0fromB in order to indicate AduB to startaccepting t,e file names from stdin) "fter entering eac, file name press ctrl\@ t+ice in order toproduce t,e output for t,at file)

3) End t,e output +it, null !te using 0(


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If !ou +is, to produce eac, output ending +it,out a ne+line ut +it, a null !te instead t,enuse t,e 0( flag)

2 du 0am 0(

( )/red,at/r,7% )/red,at% )/testfile)txt( )/linux#ernel( )/uuntu/u%(% )/uunt

u%

So +e see t,at t,e output ao-e +as produced in a single line as eac, output +as terminated+it, a ( !te)

7) CustomiVe t,e loc* siVe in output t,roug, loc*0siVe

.al*ing of loc* siVe' some times it is reDuired to ,a-e output in a different +a!) 5or example :

2 du 0ac

( )/red,at/r,7

8 )/red,at

8 )/testfile)txt

( )/linux#ernel

( )/uuntu/u%(

8 )/uuntu

%3 )

%3 total

.,e ao-e output is represented in terms of numer of %(&8 !tes loc*s) No+ suppose if +ereDuire t,e output to e in numer of &(8; !tes loc*' t,en in t,is case t,e flag Aloc*0siVeBcan e used)

2 du 0a,c 00loc*0siVe&(8;

( )/red,at/r,7

& )/red,at

& )/testfile)txt

( )/linux#ernel

( )/uuntu/u%(

& )/uuntu


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; )

; total

So +e see t,at t,e ao-e output is in t,e form of numer of &(8; !tes loc*s)

;) @ispla! output in !tes using 0

.o get t,e output in terms of !tes' t,e 0 flag can e used)

2 du 0ac,

( )/red,at/r,7

8(=3 )/red,at

)/testfile)txt

( )/linux#ernel( )/uuntu/u%(

8(=3 )/uuntu

%&&=% )

%&&=% total

So +e see t,at t,e ao-e output is in terms of !tes)

=) Exclude particular t!pes of files1 using exclude

Suppose +e do not +ant to ,a-e t,e statistics of )txt files) So for t,ese t!pes of reDuirementst,ere is a AexcludeB flag)

2 du 0c,a 00exclude])txt

( )/red,at/r,7

8)(# )/red,at

( )/linux#ernel

( )/uuntu/u%(

8)(# )/uuntu

% )

% total

So +e see t,at in t,e output ao-e' t,e text file entr! +as not t,ere)


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%() @ispla! t,e modification time and customiVe t,e displa! st!le

.,is can e ac,ie-ed t,roug, time and time0st!le flags)

2 du 0c,a 00time

( &(%&0(40&& &%:4& )/red,at/r,7

8)(# &(%&0(40&& &%:4& )/red,at

&(%&0(30%; %=:& )/testfile)txt

( &(%&0(40&& &%:4& )/linux#ernel

( &(%&0(40&& &%:4& )/uuntu/u%(

8)(# &(%&0(40&& &%:4& )/uuntu

%# &(%&0(30%; %=:& )%# &(%&0(30%; %=:& total

2 du 0c,a 00time 00time0st!leiso

( &(%&0(40&& )/red,at/r,7

8)(# &(%&0(40&& )/red,at

&(%&0(30%; )/testfile)txt

( &(%&0(40&& )/linux#ernel

( &(%&0(40&& )/uuntu/u%(

8)(# &(%&0(40&& )/uuntu

%# &(%&0(30%; )

%# &(%&0(30%; total

5or time0st!le' !ou can also use full0iso' long0iso' iso)

S+itc,es:

du ta*es a single argument' specif!ing a pat,name for du to +or*Y if it is not specified' t,ecurrent director! is used) .,e SUS mandates for du t,e follo+ing options:

0a' displa! an entr! for eac, file and not director!1 contained in t,e current director!

0c' displa! a grand total of t,e dis* usage found ! t,e ot,er arguments


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0d ' t,e dept, at +,ic, summing s,ould occur) 0d ( sums at t,e current le-el' 0d % sums at t,esudirector!' 0d & at su0sudirectories' etc)

0J' calculate dis* usage for lin* references specified on t,e command line

0*' s,o+ siVes as multiples of %(&8 !tes'not 4%&0!te

0L' calculate dis* usage for lin* references an!+,ere

0s' report onl! t,e sum of t,e usage in t,e current director!' not for eac, file

0x' onl! tra-erse files and directories on t,e de-ice on +,ic, t,e pat,name argument isspecified)

t,er Unix and Unix0li*e operating s!stems ma! add extra options) 5or example' ?S@ andWNU duspecif! a 0, option' displa!ing dis* usage in a format easier to read ! t,e user' addingunits +it, t,e appropriate SI prefix e)g) %( M?1))

ptions

0a' 00all +rite counts for all files' not ust directories)

00apparent0siVe print apparent siVes' rat,er t,an dis* usageY alt,oug, t,e apparent siVe is usuallma! e larger due to ,oles in ^sparse^1 files' internal fragmentation' indirect locli*e)

0?' 00loc*0

siVeSITE

scale siVes ! SITE efore printing t,em) 5or example' ^0?M^ prints siVes in units

%'(8;'473 !tes) See SITE format elo+1)

0' 00!tes eDui-alent to ^00apparent0siVe 00loc*0siVe%^

0c' 00total displa! a grand total)

0@' 00dereference0args

dereference onl! s!mlin*s t,at are listed on t,e command line)

00files(0from5 summariVe dis* usage of t,e NUL0terminated file namesspecified in file 5Y If 5 isnames from standard input)

0J eDui-alent to 00dereference0args 0@1)

0,' 00,uman0 print siVes in ,uman readale format' rounding -alues and using are-iations) 5
http://en.wikipedia.org/wiki/Bytehttp://en.wikipedia.org/wiki/Bytehttp://en.wikipedia.org/wiki/SI_prefixhttp://en.wikipedia.org/wiki/SI_prefixhttp://en.wikipedia.org/wiki/Megabytehttp://en.wikipedia.org/wiki/Megabytehttp://www.computerhope.com/jargon/d/director.htmhttp://www.computerhope.com/jargon/d/director.htmhttp://www.computerhope.com/jargon/f/filefrag.htmhttp://www.computerhope.com/jargon/f/filefrag.htmhttp://www.computerhope.com/jargon/b/block.htmhttp://www.computerhope.com/jargon/s/symblink.htmhttp://www.computerhope.com/jargon/s/symblink.htmhttp://www.computerhope.com/jargon/c/commandi.htmhttp://www.computerhope.com/jargon/c/commandi.htmhttp://www.computerhope.com/jargon/n/nullchar.htmhttp://www.computerhope.com/jargon/n/nullchar.htmhttp://www.computerhope.com/jargon/f/filename.htmhttp://www.computerhope.com/jargon/f/filename.htmhttp://www.computerhope.com/jargon/s/stdin.htmhttp://www.computerhope.com/jargon/s/stdin.htmhttp://en.wikipedia.org/wiki/Bytehttp://en.wikipedia.org/wiki/SI_prefixhttp://en.wikipedia.org/wiki/Megabytehttp://www.computerhope.com/jargon/d/director.htmhttp://www.computerhope.com/jargon/f/filefrag.htmhttp://www.computerhope.com/jargon/b/block.htmhttp://www.computerhope.com/jargon/s/symblink.htmhttp://www.computerhope.com/jargon/c/commandi.htmhttp://www.computerhope.com/jargon/n/nullchar.htmhttp://www.computerhope.com/jargon/f/filename.htmhttp://www.computerhope.com/jargon/s/stdin.htm


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readale %#' &8M' &W' etc)

00si li*e 0,' ut use po+ers of %(((' not %(&8)

0* li*e 00loc*0siVe%#)

0l' 00count0lin*s count siVes man! times if ,ard0lin*ed)

0m li*e 00loc*0siVe%M)

0L' 00dereference dereference all s!molic lin*s)

0P' 00no0dereference don^t follo+ an! s!molic lin*s t,is is t,e default1)

0(' 00null end eac, output line +it, ( !te rat,er t,an ne+line)

0S' 00separate0dirs do not include siVe of sudirectories)

0s' 00summariVe displa! onl! a total for eac, argument)

0x' 00one0file0s!stem

s*ip directories on different file s!stems)

0X' 00exclude0from5ILE

exclude files t,at matc, an! pattern in 5ILE

00excludeP"..E$N

exclude files t,at matc, P"..E$N)

0d' 00max0dept,N print t,e total for a director! or file' +it, 00all1 onl! if it is N or fe+er le-els elo+ command line argumentY 00max0dept,(is t,e same as 00summariVe)

00time s,o+ time of t,e last modification of an! file in t,e director!' or an! of its sudire
http://www.computerhope.com/jargon/h/hardlink.htmhttp://www.computerhope.com/jargon/h/hardlink.htmhttp://www.computerhope.com/jargon/n/newline.htmhttp://www.computerhope.com/jargon/n/newline.htmhttp://www.computerhope.com/jargon/s/subdirec.htmhttp://www.computerhope.com/jargon/s/subdirec.htmhttp://www.computerhope.com/jargon/h/hardlink.htmhttp://www.computerhope.com/jargon/n/newline.htmhttp://www.computerhope.com/jargon/s/subdirec.htm


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00time>$@ s,o+ time as >$@ instead of modification time: atime'access' use' ctime or st

00time0st!leS.LE

s,o+ times using st!le S.LE: full0iso' long0iso' iso' or\5$M".) 5$M". is li*e t,e format of date^)1

00,elp displa! a ,elp message and exit)

00-ersion output -ersion information and exit)

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

ou s,ould get a grip on t,e Linux grep command)

.,is is part of t,e on0going %4 Examples series' +,ere %4 detailed examples +ill e pro-ided fora specific command or functionalit!) Earlier +e discussed %4 practical examples for Linux findcommand' Linuxcommand line ,istor! and m!sDladmin command)

In t,is article let us re-ie+ %4 practical examples of Linux grep command t,at +ill e -er! usefulto ot, ne+ies and experts)

5irst create t,e follo+ing demofile t,at +ill e used in t,e examples elo+ to demonstrate grepcommand)

2 cat demofile

.JIS LINE IS .JE %S. UPPE$ C"SE LINE IN .JIS 5ILE)

t,is line is t,e %st lo+er case line in t,is file)

.,is Line Jas "ll Its 5irst C,aracter f .,e >ord >it, Upper Case)

.+o lines ao-e t,is line is empt!)

"nd t,is is t,e last line)
http://www.computerhope.com/jargon/d/date.htmhttp://www.computerhope.com/jargon/d/date.htmhttp://www.thegeekstuff.com/2009/03/15-practical-linux-find-command-examples/http://www.thegeekstuff.com/2009/03/15-practical-linux-find-command-examples/http://www.thegeekstuff.com/2009/03/15-practical-linux-find-command-examples/http://www.thegeekstuff.com/2008/08/15-examples-to-master-linux-command-line-history/http://www.thegeekstuff.com/2009/01/15-practical-usages-of-mysqladmin-command-for-administering-mysql-server/http://www.thegeekstuff.com/2009/01/15-practical-usages-of-mysqladmin-command-for-administering-mysql-server/http://www.computerhope.com/jargon/d/date.htmhttp://www.thegeekstuff.com/2009/03/15-practical-linux-find-command-examples/http://www.thegeekstuff.com/2009/03/15-practical-linux-find-command-examples/http://www.thegeekstuff.com/2008/08/15-examples-to-master-linux-command-line-history/http://www.thegeekstuff.com/2009/01/15-practical-usages-of-mysqladmin-command-for-administering-mysql-server/


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%) Searc, for t,e gi-en string in a single file

.,e asic usage of grep command is to searc, for a specific string in t,e specified file as s,o+nelo+)

S!ntax:

grep literalstring filename

2 grep t,is demofile



&) C,ec*ing for t,e gi-en string in multiple files)

S!ntax:

grep string 5ILEP"..E$N

.,is is also a asic usage of grep command) 5or t,is example' let us cop! t,e demofile todemofile%) .,e grep output +ill also include t,e file name in front of t,e line t,at matc,ed t,especific pattern as s,o+n elo+) >,en t,e Linux s,ell sees t,e meta c,aracter' it does t,eexpansion and gi-es all t,e files as input to grep)

2 cp demofile demofile%

2 grep t,is demo]

demofile:t,is line is t,e %st lo+er case line in t,is file)

demofile:.+o lines ao-e t,is line is empt!)

demofile:"nd t,is is t,e last line)

demofile%:t,is line is t,e %st lo+er case line in t,is file)

demofile%:.+o lines ao-e t,is line is empt!)

demofile%:"nd t,is is t,e last line)

) Case insensiti-e searc, using grep 0i

S!ntax:

grep 0i string 5ILE


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.,is is also a asic usage of t,e grep) .,is searc,es for t,e gi-en string/pattern caseinsensiti-el!) So it matc,es all t,e +ords suc, as Ft,eH' F.JEH and F.,eH case insensiti-el! ass,o+n elo+)

2 grep 0i t,e demofile.JIS LINE IS .JE %S. UPPE$ C"SE LINE IN .JIS 5ILE)




8) Matc, regular expression in files

S!ntax:

grep $EWEX filename

.,is is a -er! po+erful feature' if !ou can use use regular expression effecti-el!) In t,e follo+ingexample' it searc,es for all t,e pattern t,at starts +it, FlinesH and ends +it, Fempt!H +it,an!t,ing in0et+een) i)e .o searc, Flines9an!t,ing in0et+eenempt!H in t,e demofile)

2 grep lines)]empt! demofile


5rom documentation of grep: " regular expression ma! e follo+ed ! one of se-eral repetitionoperators:

6 .,e preceding item is optional and matc,ed at most once)

] .,e preceding item +ill e matc,ed Vero or more times)

\ .,e preceding item +ill e matc,ed one or more times)

_n` .,e preceding item is matc,ed exactl! n times)

_n'` .,e preceding item is matc,ed n or more times)

_'m` .,e preceding item is matc,ed at most m times)

_n'm` .,e preceding item is matc,ed at least n times' ut not more t,an m times)

4) C,ec*ing for full +ords' not for su0strings using grep 0+

If !ou +ant to searc, for a +ord' and to a-oid it to matc, t,e sustrings use 0+ option) ustdoing out a normal searc, +ill s,o+ out all t,e lines)


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.,e follo+ing example is t,e regular grep +,ere it is searc,ing for FisH) >,en !ou searc, for FisH'+it,out an! option it +ill s,o+ out FisH' F,isH' Ft,isH and e-er!t,ing +,ic, ,as t,e sustring FisH)

2 grep 0i is demofile






.,e follo+ing example is t,e >$@ grep +,ere it is searc,ing onl! for t,e +ord FisH) Please

note t,at t,is output does not contain t,e line F.,is Line Jas "ll Its 5irst C,aracter f .,e >ord>it, Upper CaseH' e-en t,oug, FisH is t,ere in t,e F.,isH' as t,e follo+ing is loo*ing onl! for t,e+ord FisH and not for Ft,isH)

2 grep 0i+ is demofile





3) @ispla!ing lines efore/after/around t,e matc, using grep 0"' 0? and 0C

>,en doing a grep on a ,uge file' it ma! e useful to see some lines after t,e matc,) ou mig,tfeel ,and! if grep can s,o+ !ou not onl! t,e matc,ing lines ut also t,e linesafter/efore/around t,e matc,)

Please create t,e follo+ing demotext file for t,is example)

2 cat demotext

8) im >ord Na-igation

ou ma! +ant to do se-eral na-igation in relation to t,e +ords' suc, as:


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] e 0 go to t,e end of t,e current +ord)

] E 0 go to t,e end of t,e current >$@)

] 0 go to t,e pre-ious efore1 +ord)

] ? 0 go to t,e pre-ious efore1 >$@)

] + 0 go to t,e next +ord)

] > 0 go to t,e next >$@)

>$@ 0 >$@ consists of a seDuence of non0lan* c,aracters' separated +it, +,ite space)

+ord 0 +ord consists of a seDuence of letters' digits and underscores)

Example to s,o+ t,e difference et+een >$@ and +ord

] %=&)%3;)%)% 0 single >$@

] %=&)%3;)%)% 0 se-en +ords)

3)% @ispla! N lines after matc,

0" is t,e option +,ic, prints t,e specified N lines after t,e matc, as s,o+n elo+)

S!ntax:

grep 0" Nb string 5ILEN"ME

.,e follo+ing example prints t,e matc,ed line' along +it, t,e lines after it)

2 grep 0" 0i example demotext


] %=&)%3;)%)% 0 single >$@

] %=&)%3;)%)% 0 se-en +ords)

3)& @ispla! N lines efore matc,

0? is t,e option +,ic, prints t,e specified N lines efore t,e matc,)


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S!ntax:

grep 0? Nb string 5ILEN"ME

>,en !ou ,ad option to s,o+ t,e N lines after matc,' !ou ,a-e t,e 0? option for t,e opposite)

2 grep 0? & single >$@ demotext


] %=&)%3;)%)% 0 single >$@

3) @ispla! N lines around matc,

0C is t,e option +,ic, prints t,e specified N lines efore t,e matc,) In some occasion !ou mig,t

+ant t,e matc, to e appeared +it, t,e lines from ot, t,e side) .,is options s,o+s N lines inot, t,e sideefore after1 of matc,)

2 grep 0C & Example demotext



] %=&)%3;)%)% 0 single >$@

7) Jig,lig,ting t,e searc, using W$EPP.INS

"s grep prints out lines from t,e file ! t,e pattern / string !ou ,ad gi-en' if !ou +anted it to,ig,lig,t +,ic, part matc,es t,e line' t,en !ou need to follo+ t,e follo+ing +a!)

>,en !ou do t,e follo+ing export !ou +ill get t,e ,ig,lig,ting of t,e matc,ed searc,es) In t,efollo+ing example' it +ill ,ig,lig,t all t,e t,is +,en !ou set t,e W$EPP.INS en-ironment-ariale as s,o+n elo+)

2 export W$EPP.INS^00colorauto^ W$EPCL$^%((Y;^

2 grep t,is demofile




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;) Searc,ing in all files recursi-el! using grep 0r

>,en !ou +ant to searc, in all t,e files under t,e current director! and its su director!) 0roption is t,e one +,ic, !ou need to use) .,e follo+ing example +ill loo* for t,e string Frames,H

in all t,e files in t,e current director! and all itBs sudirector!)

2 grep 0r rames, ]

=) In-ert matc, using grep 0-

ou ,ad different options to s,o+ t,e lines matc,ed' to s,o+ t,e lines efore matc,' and tos,o+ t,e lines after matc,' and to ,ig,lig,t matc,) So definitel! ouBd also +ant t,e option 0- todo in-ert matc,)

>,en !ou +ant to displa! t,e lines +,ic, does not matc,es t,e gi-en string/pattern' use t,e

option 0- as s,o+n elo+) .,is example +ill displa! all t,e lines t,at did not matc, t,e +ordFgoH)

2 grep 0- go demotext

8) im >ord Na-igation

ou ma! +ant to do se-eral na-igation in relation to t,e +ords' suc, as:

>$@ 0 >$@ consists of a seDuence of non0lan* c,aracters' separated +it, +,ite space)



] %=&)%3;)%)% 0 single >$@

] %=&)%3;)%)% 0 se-en +ords)

%() displa! t,e lines +,ic, does not matc,es all t,e gi-en pattern)

S!ntax:

grep 0- 0e pattern 0e pattern

2 cat test0file)txt


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a

c

d

2 grep 0- 0e a 0e 0e c test0file)txt

d

%%) Counting t,e numer of matc,es using grep 0c

>,en !ou +ant to count t,at ,o+ man! lines matc,es t,e gi-en pattern/string' t,en use t,eoption 0c)

S!ntax:

grep 0c pattern filename

2 grep 0c go demotext

3

>,en !ou +ant do find out ,o+ man! lines matc,es t,e pattern

2 grep 0c t,is demofile

>,en !ou +ant do find out ,o+ man! lines t,at does not matc, t,e pattern

2 grep 0- 0c t,is demofile

8

%&) @ispla! onl! t,e file names +,ic, matc,es t,e gi-en pattern using grep 0l

If !ou +ant t,e grep to s,o+ out onl! t,e file names +,ic, matc,ed t,e gi-en pattern' use t,e 0llo+er0case L1 option)

>,en !ou gi-e multiple files to t,e grep as input' it displa!s t,e names of file +,ic, contains t,etext t,at matc,es t,e pattern' +ill e -er! ,and! +,en !ou tr! to find some notes in !our +,oledirector! structure)

2 grep 0l t,is demo]


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demofile

demofile%

%) S,o+ onl! t,e matc,ed string

?! default grep +ill s,o+ t,e line +,ic, matc,es t,e gi-en pattern/string' ut if !ou +ant t,egrep to s,o+ out onl! t,e matc,ed string of t,e pattern t,en use t,e 0o option)

It mig,t not e t,at muc, useful +,en !ou gi-e t,e string straig,t for+ard) ?ut it ecomes -er!useful +,en !ou gi-e a regex pattern and tr!ing to see +,at it matc,es as

2 grep 0o is)]line demofile

is line is t,e %st lo+er case line

is line

is is t,e last line

%8) S,o+ t,e position of matc, in t,e line

>,en !ou +ant grep to s,o+ t,e position +,ere it matc,es t,e pattern in t,e file' use t,efollo+ing options as

S!ntax:

grep 0o 0 pattern file

2 cat temp0file)txt

%&84

%&84

2 grep 0o 0 temp0file)txt

&:

;:

Note: .,e output of t,e grep command ao-e is not t,e position in t,e line' it is !te offset of t,e+,ole file)

%4) S,o+ line numer +,ile displa!ing t,e output using grep 0n

.o s,o+ t,e line numer of file +it, t,e line matc,ed) It does %0ased line numering for eac,file) Use 0n option to utiliVe t,is feature)


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2 grep 0n go demotext

4: ] e 0 go to t,e end of t,e current +ord)

3: ] E 0 go to t,e end of t,e current >$@)

7: ] 0 go to t,e pre-ious efore1 +ord)

;: ] ? 0 go to t,e pre-ious efore1 >$@)

=: ] + 0 go to t,e next +ord)

%(: ] > 0 go to t,e next >$@)

P.INS

ption

@escription

0 @ispla! t,e loc* numer at t,e eginning of eac, line)

0c @ispla! t,e numer of matc,ed lines)

0, @ispla! t,e matc,ed lines' ut do not displa! t,efilenames)

0i Ignore case sensiti-it!)

0l @ispla! t,e filenames' ut do not displa! t,e matc,edlines)

0n @ispla! t,e matc,ed lines and t,eir line numers)

0s Silent mode)

0- @ispla! all lines t,at do N. matc,)

0+ Matc, +,ole +ord)

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ))

.P Command Examples in Linux


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?! $a-i Sai-eUnder: CentS' 5edora' Linux Commands'Linux @istros' $edJatn: Marc, 8'&(%

@o+nload our 5ree e?oo*s N> 0 %( 5ree Linux e?oo*s for "dministrators

.,is is t,e part of our on0going series of commands in Linux) >e ,a-e co-ered asic ls

command and cat command) In t,is article' +e are tr!ing to explore top command +,ic, is oneof t,e most freDuentl! used commands in our dail! s!stem administrati-e os) topcommanddispla!s processor acti-it! of !our Linux ox and also displa!s tas*s managed ! *ernel in real0time) ItBll s,o+ processor and memor! are eing used and ot,er information li*e runningprocesses) .,is ma! ,elp !ou to ta*e correct action) top command found in UNIX0li*e operatings!stems)

Linux .op Command Examples

ou mig,t also e interested in follo+ing tutorials :

Jtop Linux Process Monitoring1 tool for $JEL' CentS 5edora

Iotop Monitor Linux @is* I/1 in $JEL' CentS and 5edora

%) @ispla! of .op Command

In t,is example' it +ill s,o+ information li*e tas*s' memor!' cpu and s+ap) Press ADA to Duit+indo+)

top
http://www.tecmint.com/author/admin/http://www.tecmint.com/category/linux-distros/centos/http://www.tecmint.com/category/linux-distros/fedora/http://www.tecmint.com/category/linux-commands/http://www.tecmint.com/category/linux-distros/http://www.tecmint.com/category/linux-distros/http://www.tecmint.com/category/linux-distros/redhat/http://www.tecmint.com/10-useful-free-linux-ebooks-for-newbies-and-administrators/http://www.tecmint.com/15-basic-ls-command-examples-in-linux/http://www.tecmint.com/15-basic-ls-command-examples-in-linux/http://www.tecmint.com/13-basic-cat-command-examples-in-linux/http://www.tecmint.com/install-htop-linux-process-monitoring-for-rhel-centos-fedora/http://www.tecmint.com/install-iotop-monitor-linux-disk-io-in-rhel-centos-and-fedora/http://www.tecmint.com/wp-content/uploads/2012/08/Linux-Top-Commands.pnghttp://www.tecmint.com/author/admin/http://www.tecmint.com/category/linux-distros/centos/http://www.tecmint.com/category/linux-distros/fedora/http://www.tecmint.com/category/linux-commands/http://www.tecmint.com/category/linux-distros/http://www.tecmint.com/category/linux-distros/redhat/http://www.tecmint.com/10-useful-free-linux-ebooks-for-newbies-and-administrators/http://www.tecmint.com/15-basic-ls-command-examples-in-linux/http://www.tecmint.com/15-basic-ls-command-examples-in-linux/http://www.tecmint.com/13-basic-cat-command-examples-in-linux/http://www.tecmint.com/install-htop-linux-process-monitoring-for-rhel-centos-fedora/http://www.tecmint.com/install-iotop-monitor-linux-disk-io-in-rhel-centos-and-fedora/


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Linux .op Command

&) Sorting +it, 0 Uppercase Letter AB1)Press S,ift\1 to Sort field -ia field letter' for example press AaA letter to sort process +it, PI@Process I@1)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Command.jpg


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Sorting Process I@Bs +it, .op

.!pe an! *e! to return to main top +indo+ +it, sorted PI@ order as s,o+n in elo+ screen)Press ADA to Duit exit t,e +indo+)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Sort.jpg


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Sorting Process I@Bs

) @ispla! Specific User ProcessUse top command +it, AuA option +ill displa! specific User process details)

top 0u tecmint
http://www.tecmint.com/wp-content/uploads/2012/08/Sort-with-PID.jpg


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.op +it, Specific User Processes

8) Jig,lig,t $unning Process in .opPress AVA option in running top command +ill displa! running process in color +,ic, ma! ,elp!ou to identified running process easil!)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-User-Process.jpg


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.op Process +it, Colorful

4) S,o+s "solute Pat, of ProcessesPress AcA option in running top command' it +ill displa! asolute pat, of running process)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Colorful.png


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.op +it, Specific Process Pat,

3) C,ange @ela! or Set AScreen $efres, Inter-alB in .op

?! default screen refres, inter-al is )( seconds' same can e c,ange pressing AdA option inrunning top command and c,ange it as desired as s,o+n elo+)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-command-with-Path.jpg


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.op Set $efres, .ime

7) #ill running process +it, argument A*B

ou can *ill a process after finding PI@ of process ! pressing A*A option in running topcommand +it,out exiting from top +indo+ as s,o+n elo+)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Set-Refresh-Time.jpg


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.op #ill Process I@

;) Sort ! CPU Utilisation

Press S,ift\P1 to sort processes as per CPU utiliVation) See screens,ot elo+)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Kill-Process.jpg


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.op Jig, CPU UtiliVation

=) $enice a Process

ou can use ArA option to c,ange t,e priorit! of t,e process also called $enice)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-With-CPU-Utilization.jpg


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.op $enice Process

%() Sa-e .op Command $esults

Press S,ift\>1 to sa-e t,e running top command results under /root/)toprc)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Renice-Process.jpg


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.op Command Sa-e $esults

%%) Wetting .op Command Jelp

Press A,A option to otain t,e top command ,elp)
http://www.tecmint.com/wp-content/uploads/2012/08/Top-Save-Results.jpg


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.op Command Jelp

%&) Exit .op Command "fter Specific repetition

.op output *eep refres,ing until !ou press ADA) >it, elo+ command top command +illautomaticall! exit after %( numer of repetition)

top 0n %(

.,ere are numer of arguments to *no+ more aout top command !ou ma! refer man pageof top command) Please s,are it if !ou find t,is article useful t,roug, our comment ox elo+)

P.INS

pid)))

Specif! t,e list of processes t,at *ill s,ould signal) Eac, pid can e one of fi-e t,ings:

n
http://www.tecmint.com/wp-content/uploads/2012/08/Top-command-help.jpg


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+,ere n is larger t,an () .,e process +it, pid n +ill e signaled)

(

"ll processes in t,e current process group are signaled)

0%

"ll processes +it, pid larger t,an % +ill e signaled)

0n

+,ere n is larger t,an %) "ll processes in process group n are signaled) >,en an argument oft,e form 0n^ is gi-en' and it is meant to denote a process group' eit,er t,e signal must especified first' or t,e argument must e preceded ! a 00^ option' ot,er+ise it +ill e ta*en ast,e signal to send)

commandname

"ll processes in-o*ed using t,at name +ill e signaled)

0s signal

Specif! t,e signal to send) .,e signal ma! e gi-en as a signal name or numer)

0l

Print a list of signal names) .,ese are found in /usr/include/linux/signal),

0a

@o not restrict t,e commandname0to0pid con-ersion to processes +it, t,e same uid as t,epresent process)

0p

Specif! t,at *ill s,ould onl! print t,e process id pid1 of t,e named processes' and not send an!signals)

7 Linux fdis* Command Examples to Manage Jard @is* Partition

! ?"L"#$ISJN"N M"$I"PP"N on SEP.EM?E$ %8' &(%(


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n Linux distriutions' fdis* is t,e est tool tomanage dis* partitions) fdis* is a text ased utilit!)

Using fdis* !ou can create a ne+ partition' delete an existing partition' or c,ange existingpartition)

Using fids* !ou are allo+ed to create a maximum of four primar! partition' and an! numer oflogical partitions' ased on t,e siVe of t,e dis*)

#eep in mind t,at an! single partition reDuires a minimum siVe of 8(M?)

In t,is article' let us re-ie+ ,o+ to use fdis* command using practical examples)

>arning: @onBt delete' modif!' or add partition' if !ou donBt *no+ +,at !ou are doing) ou +illlose !our data

%) ie+ "ll Existing @is* Partitions Using fdis* 0l?efore !ou create a ne+ partition' or modif! an existing partition' !ou mig,t +ant to -ie+ alla-ailale partition in t,e s!stem)

Use fdis* 0l to -ie+ all a-ailale partitions as s,o+n elo+)

fdis* 0l


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@is* /de-/sda: ;()( W?' ;((&33%;43 !tes

&44 ,eads' 3 sectors/trac*' =7&= c!linders

Units c!linders of %3(34 ] 4%& ;&&4&;( !tes

@is* identifier: (xf3edf3ed

@e-ice ?oot Start End ?loc*s Id S!stem

/de-/sda% % %=4= %47433 c >=4 5".& L?"1

/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 ] %=3( &33% 43;74& ; Linux

/de-/sda3 &33& &=(8 %=4%;33 ; Linux

/de-/sda7 &=(4 %87 %=4%;33 ; Linux

/de-/sda; %8; &38 ==77% ;& Linux s+ap / Solaris

/de-/sda= &34 4&; %3&%74;3 >=4 5".&

.,e ao-e +ill list partitions from all t,e connected ,ard dis*s) >,en !ou ,a-e more t,an onedis* on t,e s!stem' t,e partitions list are ordered ! t,e de-iceBs /de- name) 5or example'/de-/sda' /de-/sd' /de-/sdc and so on)

&) ie+ Partitions of a Specific Jard @is* using fdis* 0l /de-/sd_a`

.o -ie+ all partitions of t,e /de-/sda ,ard dis*' do t,e follo+ing)

fdis* 0l /de-/sda

ie+ all fdis* Commands Using fdis* Command m

Use fdis* command m' to -ie+ all a-ailale fdis* commands as s,o+n elo+)

fdis* /de-/sda

.,e numer of c!linders for t,is dis* is set to =7&=)


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.,ere is not,ing +rong +it, t,at' ut t,is is larger t,an %(&8'

and could in certain setups cause prolems +it,:

%1 soft+are t,at runs at oot time e)g)' old -ersions of LIL1

&1 ooting and partitioning soft+are from ot,er Ss

e)g)' @S 5@IS#' S/& 5@IS#1

Command m for ,elp1: m

Command action

a toggle a ootale flag

edit sd dis*lael c toggle t,e dos compatiilit! flag

d delete a partition

l list *no+n partition t!pes

m print t,is menu

n add a ne+ partition

o create a ne+ empt! @S partition tale

p print t,e partition tale

D Duit +it,out sa-ing c,anges

s create a ne+ empt! Sun dis*lael

t c,ange a partition^s s!stem id

u c,ange displa!/entr! units

- -erif! t,e partition tale

+ +rite tale to dis* and exit

x extra functionalit! experts onl!1

) @elete a Jard @is* Partition Using fdis* Command d


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Let us assume t,at !ou li*e to comine se-eral partitions for example' /de-/sda3' /de-/sda7and /de-/sda;1 into a single dis* partition) .o do t,is' !ou s,ould first delete all t,ose indi-idualpartitions' as s,o+n elo+)

fdis* /de-/sda






e)g)' @S 5@IS#' S/& 5@IS#1

Command m for ,elp1: p

@is* /de-/sda: ;()( W?' ;((&33%;43 !tes





/de-/sda% % %=4= %47433 c >=4 5".& L?"1

/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S

/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 ] %=3( &33% 43;74& ; Linux

/de-/sda3 &33& &=(8 %=4%;33 ; Linux

/de-/sda7 &=(4 %87 %=4%;33 ; Linux


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/de-/sda; %8; &38 ==77% ;& Linux s+ap / Solaris

/de-/sda= &34 4&; %3&%74;3 >=4 5".&

Command m for ,elp1: d

Partition numer %0=1: ;

Command m for ,elp1: d

Partition numer %0;1: 7

Command m for ,elp1: dPartition numer %071: 3

Command m for ,elp1: +

.,e partition tale ,as een altered

Calling ioctl1 to re0read partition tale)

>"$NINW: $e0reading t,e partition tale failed +it, error %3: @e-ice or resource us!)

.,e *ernel still uses t,e old tale) .,e ne+ tale +ill e used at

t,e next reoot or after !ou run partproe;1 or *partx;1

S!ncing dis*s)

8) Create a Ne+ @is* Partition +it, Specific SiVe Using fdis* Command n

nce !ouB-e deleted all t,e existing partitions' !ou can create a ne+ partition using all a-ailalespace as s,o+n elo+)

fdis* /de-/sda



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e)g)' @S 5@IS#' S/& 5@IS#1

Command m for ,elp1: n

5irst c!linder &33&04&;' default &33&1:

Using default -alue &33&

Last c!linder' \c!linders or \siVe_#'M'W` &33&0&38' default &381:Using default -alue &38

In t,e ao-e example' fdis* n command is used to create ne+ partition +it, t,e specific siVe)>,ile creating a ne+ partition' it expects follo+ing t+o inputs)

Starting c!linder numer of t,e partition to e create 5irst c!linder1)

SiVe of t,e partition or1 t,e last c!linder numer Last c!linder' \c!linders or \siVe 1)

Please *eep in mind t,at !ou s,ould issue t,e fdis* +rite command +1 after an! modifications)

Command m for ,elp1: +






S!ncing dis*s)

"fter t,e partition is created' format it using t,e m*fs commandas s,o+n elo+)

m*fs)ext /de-/sda7
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4) ie+ t,e SiVe of an existing Partition Using fdis* 0s

"s s,o+n elo+' fdis* 0s displa!s t,e siVe of t,e partition in loc*s)

fdis* 0s /de-/sda7

8;8433

.,e ao-e output corresponds to aout 8=((M?)

3) .oggle t,e ?oot 5lag of a Partition Using fdis* Command a

5dis* command displa!s t,e oot flag of eac, partition) >,en !ou +ant to disale or enale t,eoot flag on t,e corresponding partition' do t,e follo+ing)

If !ou donBt *no+ +,! are !ou are doing t,is' !ouBll mess0up !our s!stem)

fdis* /de-/sda






e)g)' @S 5@IS#' S/& 5@IS#1


@is* /de-/sda: ;()( W?' ;((&33%;43 !tes





/de-/sda% % %=4= %47433 c >=4 5".& L?"1


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/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S

/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 ] %=3( &33% 43;74& ; Linux

/de-/sda3 &34 4&; %3&%74;3 >=4 5".&

/de-/sda7 &33& &38 8;8433 ; Linux

Partition tale entries are not in dis* order

Command m for ,elp1: aPartition numer %071: 4


@is* /de-/sda: ;()( W?' ;((&33%;43 !tes





/de-/sda% % %=4= %47433 c >=4 5".& L?"1

/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S

/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 %=3( &33% 43;74& ; Linux

/de-/sda3 &34 4&; %3&%74;3 >=4 5".&


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/de-/sda7 &33& &38 8;8433 ; Linux


Command m for ,elp1:

"s seen ao-e' t,e oot flag is disaled on t,e partition /de-/sda4)

7) 5ix Partition .ale rder Using fdis* Expert Command f

>,en !ou delete a logical partition' and recreate it again' !ou mig,t see t,e Fpartition out oforderH issue) i)e FPartition tale entries are not in dis* orderH error message)

5or example' +,en !ou delete t,ree logical partitions sda3' sda7 and sda;1' and create a ne+

partition' !ou mig,t expect t,e ne+ partition name to e sda3) ?ut' t,e s!stem mig,tB-e createdt,e ne+ partition as sda7) .,is is ecause' after t,e partitions are deleted' sda= partition ,aseen mo-ed as sda3 and t,e free space is mo-ed to t,e end)

.o fix t,is partition order issue' and assign sda3 to t,e ne+l! created partition' execute t,eexpert command f as s,o+n elo+)

2 fdis* /de-/sda






e)g)' @S 5@IS#' S/& 5@IS#1


@is* /de-/sda: ;()( W?' ;((&33%;43 !tes



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/de-/sda% % %=4= %47433 c >=4 5".& L?"1

/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S

/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 ] %=3( &33% 43;74& ; Linux

/de-/sda3 &34 4&; %3&%74;3 >=4 5".&/de-/sda7 &33& &38 8;8433 ; Linux


Command m for ,elp1: x

Expert command m for ,elp1: f

@one)

Expert command m for ,elp1: +






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S!ncing dis*s)

nce t,e partition tale order is fixed' !ouBll not get t,e FPartition tale entries are not in dis*orderH error message an!more)

fdis* 0l

@is* /de-/sda: ;()( W?' ;((&33%;43 !tes





/de-/sda% % %=4= %47433 c >=4 5".& L?"1

/de-/sda& %=3( 4&; &37(((( f >=4 Ext^d L?"1

/de-/sda 4&;8 34&; %((((83&\ 7 JP5S/N.5S

/de-/sda8 34&= =7&= &47%&(&\ c >=4 5".& L?"1

/de-/sda4 ] %=3( &33% 43;74& ; Linux

/de-/sda3 &33& &38 8;8433 ; Linux

/de-/sda7 &34 4&; %3&%74;3 >=4 5".&

Jo+.o: Linux List @is* Partitions Command

! NIX C$"5. on 5E?$U"$ &8' &(%& 4 CMMEN.SL"S. UP@".E@ C.?E$ ' &(%&

in LINUX
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Jo+ do I list all ,ard dis* partitions under Linux operating s!stems6

Usuall!' !our ,ard dis* dri-e di-ided into one or more logical dis*s called partitions) .,is di-isionis descried in t,e partition tale found in sector ( of t,e ,ard dis*)

.utorial details

@ifficult!Eas! rss1

$oot pri-ileges es

$eDuirements None

Estimated completiontime

N/"

.,e de-ice is usuall! /de-/sda' /de-/sd or so) " de-ice name refers to t,e entire dis* and t,ede-ice name +ill e as follo+s:

/de-/,d] 0 I@E dis*s) /de-/,da +ill e first I@E ,ard dis*' /de-/,d +ill e second I@E ,ard dis*'and so on)

/de-/sd] 0 SCSI or S"." dis*s) /de-/sda +ill e first S"."/SCSI ,ard dis*' /de-/sd +ill esecond S"."/SCSI ,ard dis*' and so on)

>"$NINW .,ese examples ma! cras, !our computer if N. executed +it, proper care)?E EX.$EMEL C"$E5UL >I.J .JE 5LL>INW CMM"N@S) NE .PINW MIS."#E"N@ "LL U$ @"." IS LS.)

lsl* Command

.o list all loc* de-ices' run: lsl*Sample outputs:

N"ME M":MIN $M SITE $ .PE MUN.PIN.
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sda ;:( % 44;W ( dis*

sda% ;:% % (7M ( part /oot

sda& ;:& % &4(W ( part /+eroot

sda ;: % 3W ( part 9S>"P

sda8 ;:8 % %# ( part

h sda4 ;:4 % (%)7W ( part /

sr( %%:( % %(&8M ( rom

List Partitions Under Linux

pen a terminal +indo+ select "pplications b "ccessories b .erminal1) S+itc, to t,e root user! t!ping su 0 and entering t,e root pass+ord' +,en prompted) r use sudo command:

2 su 0 fdis* 0l$2 sudo fdis* 0lSample outputs:

@is* /de-/sda: &4%)% W?' &4%(4=488(38 !tes

&44 ,eads' 3 sectors/trac*' (4&& c!linders


Sector siVe logical/p,!sical1: 4%& !tes / 4%& !tes

I/ siVe minimum/optimal1: 4%& !tes / 4%& !tes

@is* identifier: (x(((;fcd


/de-/sda% ] % %8 %(888; ; Linux

Partition % does not end on c!linder oundar!)

/de-/sda& %8 %(3; %(8;473(( ; Linux

/de-/sda %(3; %%=; %(8;473 ;& Linux s+ap / Solaris

/de-/sda8 %%=; (4& %=%338; 4 Extended

/de-/sda4 %%=; (4& %=%3&3&8 ; Linux


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.,e 0l options s,o+s t,e partition tales for t,e specified de-ices and t,en exit) If no de-ices aregi-en' t,ose mentioned in /proc/partitions if t,at exists1 are used) ou can specif! de-ice nameas follo+s in t,is example list partitions for /de-/sda1: fdis* 0l

sfdis* Command.,e sfdis* command act as a partition tale manipulator for Linux) ou can use t,is tool to listpartitions too: sfdis* 0l /de-/sda sfdis* 0lu /de-/sda sfdis* 0ls /de-/sdaSample outputs:

7%33=73(

@is* /de-/sda: ;=&& c!linders' &44 ,eads' 3 sectors/trac*

Units c!linders of ;&&4&;( !tes' loc*s of %(&8 !tes' counting from (

@e-ice ?oot Start End c!ls loc*s Id S!stem

/de-/sda% ] (\ %(80 %(40 ;;343 ; Linux

/de-/sda& %(8\ &40 %%0 %(8;473 ;& Linux s+ap / Solaris

/de-/sda &4\ ;=&&0 ;3;;0 3=7;%4(8 ; Linux

/de-/sda8 ( 0 ( ( ( Empt!

>,ere'

0l : List t,e partitions of a de-ice)

0s : List t,e siVe of a partition)

0u or 0uS or 0u? or 0uC or 0uM : "ccept or report in units of sectors loc*s' c!linders'mega!tes' respecpi-el!1) .,e default is c!linders' at least +,en t,e geometr! is *no+n)

Listing Linux a Partition SiVe Larger .,an &.?

.,e fdis* or sfdis* command+ill not list an! partition siVe larger t,an &.?) .o sol-e t,isprolem !ou need to use WNU parted command +it, WP. partitions) It supports Intel E5I/WP.partition tales) Partition .ale WP.1 is a standard for t,e la!out of t,e partition tale on ap,!sical ,ard dis*) It is a part of t,e Extensile 5irm+are Interface E5I1 standard proposed !Intel as a replacement for t,e outdated PC ?IS' one of t,e fe+ remaining relics of t,e originalI?M PC) E5I uses WP. +,ere ?IS uses a Master ?oot $ecord M?$1) In t,is example listpartitions on /de-/sd using t,e parted command:
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parted /de-/sdSample outputs:

WNU Parted &)

Using /de-/sd

>elcome to WNU Parted .!pe ^,elp^ to -ie+ a list of commands)

parted1

Set unit t!pe to .? or W? ! t!ping ^unit .?^ or ^unit W?^ at t,e parted1 prompt:parted1 unit .?$parted1 unit W?.o list partitions t!pe print command at t,e parted1 prompt:parted1 print

Sample outputs:

Model: "." S.(((34%"S scsi1

@is* /de-/sd: ((%W?

Sector siVe logical/p,!sical1: 4%&?/4%&?

Partition .ale: gpt

Numer Start End SiVe 5ile s!stem Name 5lags

% ()((W? ((%W? ((%W? ext8 primar!

parted1

.o exit from parted session t!pe ^Duit^ at t,e parted1 prompt:parted1 Duit

Jo+ @o I List "ll Partitions La!out n "ll ?loc* @e-ices6

Pass t,e 0l $ 00list option to t,e parted command to lists partition la!out on all loc* de-ices: parted 0lSample outputs:


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5ig)(%: S,o+ Linux @is* Partitions >it, WNU parted Command

lssci command

Use t,e lsscsi command to s,o+ SCSI de-ices or ,osts1 and t,eir attriutes: lsscsiSample outputs:

9(:(:(:( dis* "." .SJI?" M#4(3%WS M5(( /de-/sda

9%:(:(:( cd/d-d M".SJI." ?@0$E U&&" %)%( /de-/sr(

9&:(:(:( dis* "." S.=4((8&("SW (((8 /de-/sd

Jo+.o: Use grep Command In Linux / UNIX Examples

! NIX C$"5. on "UWUS. &' &((7 &33 CMMEN.S L"S. UP@".E@ UL (' &(%

in ?"SJ SJELL'LINUX' UNIX
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Jo+ do I use grep command on Linux' "pple S X' and Unix0li*e operating s!stems6 Can !ougi-e me a simple examples of t,e grep command6

.,e grep command is used to searc, text or searc,es t,e gi-en file for lines containing a matc,to t,e gi-en strings or +ords) ?! default' grep displa!s t,e matc,ing lines) Use grep to searc,

for lines of text t,at matc, one or man! regular expressions' and outputs onl! t,e matc,inglines) grep is considered as one of t,e most useful commands on Unix and ot,er Linuxoperating s!stems)

.utorial details

@ifficult! Eas! rss 1

$oot pri-ileges No

$eDuirements grep

Estimated completiontime

%(minutes

@id !ou *no+6

.,e name' grep' deri-es from t,e command used to perform a similar operation' using t,eUnix/Linux text editor ed:g/re/p

.,e grep command s!ntax

.,e s!ntax is as follo+s:

grep ^+ord^ filename

grep ^+ord^ file% file& file

grep ^string% string&^ filename

cat ot,erfile G grep ^somet,ing^

command G grep ^somet,ing^command option% G grep ^data^

grep 00color ^data^ fileName

Jo+ do I use grep command to searc, a file6
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Searc, /etc/pass+d file for oo user' enter:2 grep oo /etc/pass+dSample outputs:

foo:x:%(((:%(((:foo''':/,ome/foo:/in/*s,

ou can force grep to ignore +ord case i)e matc, oo' ?oo' ? and all ot,er comination +it,t,e 0i option:2 grep 0i oo /etc/pass+d

Use grep recursi-el!

ou can searc, recursi-el! i)e) read all files under eac, director! for a string %=&)%3;)%)42 grep 0r %=&)%3;)%)4 /etc/$2 grep 0$ %=&)%3;)%)4 /etc/Sample outputs:

/etc/ppp/options: ms0+ins %=&)%3;)%)4(

/etc/ppp/options: ms0+ins %=&)%3;)%)4%

/etc/Net+or*Manager/s!stem0connections/>ired connection%:addresses%%=&)%3;)%)4Y&8Y%=&)%3;)%)&Y

ou +ill see result for %=&)%3;)%)4 on a separate line preceded ! t,e name of t,e file suc,as /etc/ppp/options1 in +,ic, it +as found) .,e inclusion of t,e file names in t,e output data cane suppressed ! using t,e 0, option as follo+s:2 grep 0, 0$ %=&)%3;)%)4 /etc/$2 grep 0,$ %=&)%3;)%)4 /etc/Sample outputs:

ms0+ins %=&)%3;)%)4(

ms0+ins %=&)%3;)%)4%

addresses%%=&)%3;)%)4Y&8Y%=&)%3;)%)&Y

Use grep to searc, +ords onl!

>,en !ou searc, for oo' grep +ill matc, foooo' oo%&' arfoo4 and more) ou can forcet,e grep command to select onl! t,ose lines containing matc,es t,at form +,ole +ords i)e)matc, onl! oo +ord:2 grep 0+ oo file

Use grep to searc, & different +ords


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Use t,e egrep command as follo+s:2 egrep 0+ ^+ord%G+ord&^ /pat,/to/file

Count line +,en +ords ,as een matc,ed

.,e grep can report t,e numer of times t,at t,e pattern ,as een matc,ed for eac, file using0

c count1 option:2 grep 0c ^+ord^ /pat,/to/filePass t,e 0n option to precede eac, line of output +it, t,e numer of t,e line in t,e text file from+,ic, it +as otained:2 grep 0n ^root^ /etc/pass+dSample outputs:

%:root:x:(:(:root:/root:/in/as,

%(8&:rootdoor:x:(:(:rootdoor:/,ome/rootdoor:/in/cs,

%=:initrootapp:x:(:(:initrootapp:/,ome/initroot:/in/*s,

Wrep in-ert matc,

ou can use 0- option to print in-erts t,e matc,Y t,at is' it matc,es onl! t,ose lines t,at do notcontain t,e gi-en +ord) 5or example print all line t,at do not contain t,e +ord ar:2 grep 0- ar /pat,/to/file

UNIX / Linux pipes and grep command

grep command often used +it, s,ell pipes) In t,is example' s,o+ t,e name of t,e ,ard dis*de-ices:

dmesg G egrep ^sG,1d9a0V^@ispla! cpu model name: cat /proc/cpuinfo G grep 0i ^Model^Jo+e-er' ao-e command can e also used as follo+s +it,out s,ell pipe: grep 0i ^Model^ /proc/cpuinfoSample outputs:

model : (

model name : Intel$1 Core.M1 i7 CPU ;&( < %)7WJV

model : (model name : Intel$1 Core.M1 i7 CPU ;&( < %)7WJV

Jo+ do I list ust t,e names of matc,ing files6

Use t,e 0l option to list file name +,ose contents mention main1:2 grep 0l ^main^ ])c5inall!' !ou can force grep to displa! output in colors' enter:
http://bash.cyberciti.biz/guide/Pipeshttp://bash.cyberciti.biz/guide/Pipeshttp://bash.cyberciti.biz/guide/Pipes


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2 grep 00color -i-e* /etc/pass+dSample outputs:

%( Useful du @is* Usage1 Commands to 5ind @is* Usage of 5iles and @irectories

?! $a-i Sai-eUnder: CentS' 5edora' Linux Commands'$edJatn: anuar! &%' &(%

@o+nload our 5ree e?oo*s N> 0 %( 5ree Linux e?oo*s for "dministrators.,e Linux FduH @is* Usage1 is a standard Unix/Linux command' used to c,ec* t,e informationof dis* usage of files and directories on a mac,ine) .,e du command ,as man! parameteroptions t,at can e used to get t,e results in man! formats) .,e du command also displa!s t,efiles and director! siVes in a recursi-el! manner)

C,ec* @is* Usage of 5iles and 5olders In Linux

.,is article explains %( useful FduH commands +it, t,eir examples' t,at mig,t ,elps !ou to findout t,e siVes of files and directories in Linux) .,e information pro-ided in t,is article are ta*enfrom t,e man pages of du command)

$ead "lso:

%& FdfH Command to C,ec* Linux S!stem @is* Space
http://www.tecmint.com/author/admin/http://www.tecmint.com/category/linux-distros/centos/http://www.tecmint.com/category/linux-distros/fedora/http://www.tecmint.com/category/linux-commands/http://www.tecmint.com/category/linux-distros/redhat/http://www.tecmint.com/category/linux-distros/redhat/http://www.tecmint.com/10-useful-free-linux-ebooks-for-newbies-and-administrators/http://www.tecmint.com/how-to-check-disk-space-in-linux/http://www.cyberciti.biz/faq/howto-use-grep-command-in-linux-unix/grep_command_examples/http://www.tecmint.com/author/admin/http://www.tecmint.com/category/linux-distros/centos/http://www.tecmint.com/category/linux-distros/fedora/http://www.tecmint.com/category/linux-commands/http://www.tecmint.com/category/linux-distros/redhat/http://www.tecmint.com/10-useful-free-linux-ebooks-for-newbies-and-administrators/http://www.tecmint.com/how-to-check-disk-space-in-linux/


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%) .o find out t,e dis* usage summar! of a /,ome/tecmint director! tree and eac, of its sudirectories) Enter t,e command as:

9root


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378M /,ome/tecmint

8) Using F0aH flag +it, FduH command displa!s t,e dis* usage of all t,e files and directories)

9root


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8)(# /,ome/tecmint/)moVilla/extensions

% /,ome/tecmint/)moVilla

8)(# /,ome/tecmint/)as,rc

37M /,ome/tecmint/Uuntu0%&)%(/uuntu0%&)%(0ser-er0i;3)iso

37M /,ome/tecmint/Uuntu0%&)%(

378M /,ome/tecmint

3) 5ind out t,e dis* usage of a director! tree +it, its sutress in #ilo!te lco*s) Use t,e F0*Hdispla!s siVe in %(&8 !tes units1)

9root


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;) .,e F0cH flag pro-ides a grand total usage dis* space at t,e last line) If !our director!ta*en378M? space' t,en t,e last last t+o line of t,e output +ould e)

9root


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8)(# /,ome/tecmint/)as,rc

&8# /,ome/tecmint/P,pfiles0org)tar)V&

8)(# /,ome/tecmint/geoipupdate)s,

8)(# /,ome/tecmint/)Vs,rc

%&(# /,ome/tecmint/goaccess0()8)&)tar)gV)%

37M /,ome/tecmint/Uuntu0%&)%(/uuntu0%&)%(0ser-er0i;3)iso

37M /,ome/tecmint/Uuntu0%&)%(

378M /,ome/tecmint

%() @ispla! t,e dis* usage ased on modification of time' use t,e flag FtimeH as s,o+n elo+)

9root


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8)(# &(%&0%(0%& &&:& /,ome/tecmint/)Vs,rc

%&(# &(%0(%0%= %;:& /,ome/tecmint/goaccess0()8)&)tar)gV)%

37M &(%0(%0%= %;:4% /,ome/tecmint/Uuntu0%&)%(/uuntu0%&)%(0ser-er0i;3)iso

37M &(%0(%0%= %;:4% /,ome/tecmint/Uuntu0%&)%(

378M &(%0(%0%= %;:4& /,ome/tecmint

%& Useful FdfH Commands to C,ec* @is* Space in Linux

?! $a-i Sai-eUnder: Clear S' 5edora' Linux Commands'$edJatn: anuar! %4' &(%

@o+nload our 5ree e?oo*s N> 0 %( 5ree Linux e?oo*s for "dministrators

n t,e internet !ou +ill find plent! of tools for c,ec*ing dis* space utiliVation in Linux) Jo+e-er'Linux ,as a strong uilt in utilit! called AdfA) .,e AdfA command stand for Fdis* files!stemF' it is

used to get full summar! of a-ailale and used dis* space usage of file s!stem on Linux s!stem)

Using A0,A parameter +it, df 0,1 +ill s,o+s t,e file s!stem dis* space statistics in F,umanreadaleH format' means it gi-es t,e details in !tes' mega !tes and giga!te)

Useful df Command Examples

.,is article explain a +a! to get t,e full information of Linux dis* space usage +it, t,e ,elp ofAdfA command +it, t,eir practical examples) So' !ou could etter understand t,e usage of df

command in Linux)

%) C,ec* 5ile S!stem @is* Space Usage

.,e FdfH command displa!s t,e information of de-ice name' total loc*s' total dis* space' useddis* space' a-ailale dis* space and mount points on a file s!stem)

9root


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5iles!stem %#0loc*s Used "-ailale UseQ Mounted on

/de-/cciss/c(d(p& 7;3%%=& &%;4;8( 4%%(4;; &Q /

/de-/cciss/c(d(p4 &87=7;( &&&78& %&8=7& =4Q /,ome

/de-/cciss/c(d(p &=744;; &44(7=& &7%=;8 =%Q /data

/de-/cciss/c(d(p% &=443% &%4% &4;77( ;Q /oot

tmpfs &47873 ( &47873 (Q /de-/s,m

&) @ispla! Information of all 5ile S!stem @is* Space Usage

.,e same as ao-e' ut it also displa!s information of dumm! file s!stems along +it, all t,e files!stem dis* usage and t,eir memor! utiliVation)

9root


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.,e df command pro-ides an option to displa! siVes in Juman $eadale formats ! using A0,Bprints t,e results in ,uman readale format e)g)' %# &M W11)

9root


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3) @ispla! Information of 5ile S!stem in M?

.o displa! information of all file s!stem usage in M? Mega ?!te1 use t,e option as A0mA)

9root


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/de-/cciss/c(d(p4 38(7%& 7=;3% 43(4(== %Q /,ome

/de-/cciss/c(d(p 73;488( %;;&8% 3&=7%== %=Q /data

/de-/cciss/c(d(p% 73(8 8( 73&38 %Q /oot

tmpfs 383= % 383; %Q /de-/s,m

=) @ispla! 5ile S!stem .!pe

If !ou notice all t,e ao-e commands output' !ou +ill see t,ere is no file s!stem t!pe mentionedin t,e results) .o c,ec* t,e file s!stem t!pe of !our s!stem use t,e option A.A) It +ill displa! files!stem t!pe along +it, ot,er information)

9root


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If !ou +ant to displa! file s!stem t!pe t,at doesnBt elongs to ext t!pe use t,e option as A0xA)5or example' t,e follo+ing command +ill onl! displa! ot,er file s!stems t!pes ot,er t,anext)

9root


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0x' 00exclude0t!pe.PE limit listing to file s!stems not of t!pe .PE

0- ignored1

00,elp displa! t,is ,elp and exit

00-ersion output -ersion information and exit

SITE ma! e or ma! e an integer optionall! follo+ed !1 one of follo+ing:

*? %(((' # %(&8' M? %(((]%(((' M %(&8]%(&8' and so on for W' .' P' E' T' )

$eport ugs to ug0coreutils


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bsed ^s/unix/linux/^ file)txt

linux is great os) unix is opensource) unix is free os)

learn operating s!stem)

linuxlinux +,ic, one !ou c,oose)

Jere t,e s specifies t,e sustitution operation) .,e / are delimiters) .,e unix is t,e searc,pattern and t,e linux is t,e replacement string)

?! default' t,e sed command replaces t,e first occurrence of t,e pattern in eac, line and it+on^t replace t,e second' t,ird)))occurrence in t,e line)

&) $eplacing t,e nt, occurrence of a pattern in a line)

Use t,e /%' /& etc flags to replace t,e first' second occurrence of a pattern in a line) .,e elo+command replaces t,e second occurrence of t,e +ord unix +it, linux in a line)

bsed ^s/unix/linux/&^ file)txt

unix is great os) linux is opensource) unix is free os)


unixlinux +,ic, one !ou c,oose)

) $eplacing all t,e occurrence of t,e pattern in a line)

.,e sustitute flag /g gloal replacement1 specifies t,e sed command to replace all t,eoccurrences of t,e string in t,e line)

bsed ^s/unix/linux/g^ file)txt

linux is great os) linux is opensource) linux is free os)



8) $eplacing from nt, occurrence to all occurrences in a line)


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Use t,e comination of /%' /& etc and /g to replace all t,e patterns from t,e nt, occurrence of apattern in a line) .,e follo+ing sed command replaces t,e t,ird' fourt,' fift,))) unix +ord +it,linux +ord in a line)

bsed ^s/unix/linux/g^ file)txt

unix is great os) unix is opensource) linux is free os)


unixlinux +,ic, one !ou c,oose)

4) C,anging t,e slas, /1 delimiter

ou can use an! delimiter ot,er t,an t,e slas,) "s an example if !ou +ant to c,ange t,e +eurl to anot,er url as

bsed ^s/,ttp:K/K//+++/^ file)txt

In t,is case t,e url consists t,e delimiter c,aracter +,ic, +e used) In t,at case !ou ,a-e toescape t,e slas, +it, ac*slas, c,aracter' ot,er+ise t,e sustitution +on^t +or*)

Using too man! ac*slas,es ma*es t,e sed command loo* a+*+ard) In t,is case +e canc,ange t,e delimiter to anot,er c,aracter as s,o+n in t,e elo+ example)

bsed ^s,ttp://+++^ file)txt

bsed ^sG,ttp://G+++G^ file)txt

3) Using as t,e matc,ed string

.,ere mig,t e cases +,ere !ou +ant to searc, for t,e pattern and replace t,at pattern !adding some extra c,aracters to it) In suc, cases comes in ,and!) .,e represents t,ematc,ed string)

bsed ^s/unix/_`/^ file)txt


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_unix` is great os) unix is opensource) unix is free os)


_unix`linux +,ic, one !ou c,oose)

bsed ^s/unix/_`/^ file)txt

_unixunix` is great os) unix is opensource) unix is free os)


_unixunix`linux +,ic, one !ou c,oose)

7) Using K%'K& and so on to K=

.,e first pair of parent,esis specified in t,e pattern represents t,e K%' t,e second represents t,eK& and so on) .,e K%'K& can e used in t,e replacement string to ma*e c,anges to t,e sourcestring) "s an example' if !ou +ant to replace t,e +ord unix in a line +it, t+ice as t,e +ord li*eunixunix use t,e sed command as elo+)

bsed ^s/KunixK1/K%K%/^ file)txt

unixunix is great os) unix is opensource) unix is free os)


unixunixlinux +,ic, one !ou c,oose)

.,e parent,esis needs to e escaped +it, t,e ac*slas, c,aracter) "not,er example is if !ou+ant to s+itc, t,e +ords unixlinux as linuxunix' t,e sed command is

bsed ^s/KunixK1KlinuxK1/K&K%/^ file)txt

unix is great os) unix is opensource) unix is free os)


linuxunix +,ic, one !ou c,oose)

"not,er example is s+itc,ing t,e first t,ree c,aracters in a line


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bsed ^s/[K)K1K)K1K)K1/KK&K%/^ file)txt

inux is great os) unix is opensource) unix is free os)

aelrn operating s!stem)

inuxlinux +,ic, one !ou c,oose)

;) @uplicating t,e replaced line +it, /p flag

.,e /p print flag prints t,e replaced line t+ice on t,e terminal) If a line does not ,a-e t,e searc,pattern and is not replaced' t,en t,e /p prints t,at line onl! once)

bsed ^s/unix/linux/p^ file)txt






=) Printing onl! t,e replaced lines

Use t,e 0n option along +it, t,e /p print flag to displa! onl! t,e replaced lines) Jere t,e 0noption suppresses t,e duplicate ro+s generated ! t,e /p flag and prints t,e replaced lines onl!one time)

bsed 0n ^s/unix/linux/p^ file)txt



If !ou use 0n alone +it,out /p' t,en t,e sed does not print an!t,ing)


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%() $unning multiple sed commands)

ou can run multiple sed commands ! piping t,e output of one sed command as input toanot,er sed command)

bsed ^s/unix/linux/^ file)txtG sed ^s/os/s!stem/^

linux is great s!stem) unix is opensource) unix is free os)


linuxlinux +,ic, one !ou c,os!steme)

Sed pro-ides 0e option to run multiple sed commands in a single sed command) .,e ao-e

output can e ac,ie-ed in a single sed command as s,o+n elo+)

bsed 0e ^s/unix/linux/^ 0e ^s/os/s!stem/^ file)txt

linux is great s!stem) unix is opensource) unix is free os)


linuxlinux +,ic, one !ou c,os!steme)

%%) $eplacing string on a specific line numer)

ou can restrict t,e sed command to replace t,e string on a specific line numer) "n example is

bsed ^ s/unix/linux/^ file)txt

unix is great os) unix is opensource) unix is free os)



.,e ao-e sed command replaces t,e string onl! on t,e t,ird line)

%&) $eplacing string on a range of lines)


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ou can specif! a range of line numers to t,e sed command for replacing a string)

bsed ^%' s/unix/linux/^ file)txt




Jere t,e sed command replaces t,e lines +it, range from % to ) "not,er example is

bsed ^&'2 s/unix/linux/^ file)txt

dba important linux commands

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