Khoa KTMT1

Chng V-I: Lin lc gia cc Tin Trnh

C CH ?

VN

?

TRAOITHNGTINGIACCTINTRNH

GII

PHP ?

Khoa KTMT2

Nhu Cu Lin Lc

Q

Lp

Chia s thng tin

R Phi hp tng tc x l

QL

p

JOB

Khoa KTMT3

Tn hiu M t

SIGINT Ngi dng nhn phm DEL ngt x l tin trnh

SIGQUIT Yu cu thot x l SIGILL Tin trnh x l mt ch th bt hp l SIGKILL Yu cu kt thc mt tin trnh SIGFPT Li floating point xy ra ( chia cho 0) SIGPIPE Tin trnh ghi d liu vo pipe m khng c

reader SIGSEGV Tin trnh truy xut n mt a ch bt hp l SIGCLD Tin trnh con kt thc SIGUSR1 Tn hiu 1 do ngi dng nh ngha SIGUSR2 Tn hiu 2 do ngi dng nh ngha

Cc C Ch Lin Lc

Signal : Khng truyn c d liu

Cc tn hiu c gi i bi?khi nhn th x l ra sao?

Khoa KTMT4

Cc C Ch Lin Lc

Pipe

Truyn d liu khng cu trc

Khoa KTMT5

Cc C Ch Lin Lc

Shared Memory

Mu thun truy xut => nhu cu ng b ho

Khoa KTMT6

Cc C Ch Lin Lc

Message

Lin lc trn mi trng phn tn

Lin kt tim n

Send(message) : gi mt thng ip

Receive(message) : nhn mt thng ip

Lin kt tng minh

Send(destination, message) : gi mt thng ip n destination

Receive(source,message) : nhn mt thng ip t source

Khoa KTMT7

Cc C Ch Lin Lc

Socket: l mt thit b truyn thng hai chiu nh tp tin

Mi Socket l mt thnh phn trong mt mi ni gia cc my

trong mng

Cc thuc tnh ca socket:

Domaine: nh ngha dng thc a ch v cc nghi thc s dng. C

nhiu domaines, v d UNIX, INTERNET, XEROX_NS, ...

Type: nh ngha cc c im lin lc

a) tin cy

b) bo ton th t d liu

c) Lp li d liu

d) Ch ni kt

e) Bo ton gii hn thng ip

f) Kh nng gi thng ip khn

Khoa KTMT8

Cc C Ch Lin Lc

thc hin lin lc bng socket, cn tin hnh cc thao tc :

To lp hay m mt socket

Gn kt mt socket vi mt a ch

Lin lc : c hai kiu lin lc ty thuc vo ch ni kt:

Lin lc trong ch khng lin kt - UDP

Lin lc trong ch ni kt - TCP

Hy mt socket

VD: Giao tip trong TCP

Lin kt tim n

Khoa KTMT9

Race condition

hits = hits + 1

read hits

hits =hits + 1read hits

P1 P2

hits = 1, 2 ?

hits = 0

time

Kt qu cui cng khng d on c !

P1 v P2 chia s bin chung hits

Khoa KTMT10

Vng tranh chp (Min gng - critical section)

hits = hits + 1

read hits

hits = hits + 1read hits

P1 P2

CSCS

CS l on chng trnh c kh nng gy ra hin

tng race condition

Khoa KTMT11

Gii php tng qut

Bo m tnh c quyn truy xut min gng ti

mt thi im

hits = hits + 1

P1 P2

hits = 2

hits = 0

time

hits = hits + 1

Khoa KTMT12

M hnh m bo c quyn truy xut

Kim tra v dnh quyn vo CS

CS;

T b quyn s dng CS

Khoa KTMT13

Hn h

Lm th no bo m trnh t thc hin Job1 - Job2

?

P1 P2

Job1;Job2;

Khoa KTMT14

Gii php

Hai tin trnh cn trao i thng tin v din tin x

l

P1 P2

Job1;Job2;

Khoa KTMT15

M hnh t chc phi hp hot ng gia hai

tin trnh

P1 P2

Job1; Ch ;Bo

hiu ; Job2;