Title: Presentation Last modified by: user Created Date: 2/16/1998 4:24:06 PM Document presentation format: On-screen Show (4:3) Other titles: Times New Roman Arial ...
Interprocess Communication: (3.4-3.6) CPE 261403 - Operating Systems Producer Consumer Model Producer Consumer Model Why IPC? Information Sharing Computation ...
Interprocess Communication ... Using fcntl() system call. Locking file areas ... fl_end; } Struct file_lock *file_lock_table; Linux tracks down deadlocks and ...
Every time a process exits from a system call its signal and blocked fields are ... a location in memory whose value can be tested and set (atomic) by more than one ...
Each diner either. wants to eat or 'think' (sleep) The Dining Philosophers Problem ... A diner can only move into the. EATING state if both neighbours are. HUNGRY ...
A sending process needs to communicate data to a receiving process ... Less efficient for large, frequent communications ... blocking communication mechanism ...
Interprocess Communication. and. Middleware. Sockets and Ports. Source: G. Coulouris ... The operating system includes common network protocols (TCP/IP, ...
exchange messages via send/receive. Implementation of ... send (P, message) send a ... send and receive messages through mailbox, destroy a mailbox. ...
Idempotent operation. History. Some of the above problems still exist even if one uses TCP. ... When operations have been made idempotent. At-most-once ...
Named pipe. Almost like file: name and permissions (but created by mknod) ... An improvement on pipe. Based on client-server model ... Very similar to pipe ...
Re-executing is only possible for idempotent operation ... If server operation is not idempotent a record of past results (called history) can be kept. ...
Reasons for Interprocess communication. Information sharing ... Interprocess Communication. There are two basic schemes for interprocess communication: ...
9/9/09. 1. Interprocess Communication. Remote invocations. Message passing. Streams. Multicast ... executed by a local worker process, which is invoked by the ...
Processes (Actors or Agents) can enter and leave at any time. Agent Mobility ... pattern = nickname of an actor. A brokering service model. 09-23-04. UIUIC - OSL. 26 ...
Typical applications today consist of many cooperating processes either on the ... FDDI, ATM all these use datagram style. Why? 10/31/09. B.R. 12. Functions : creation ...
What is a process? ... sets process's memory to contain code & data from executable ... we say 'process' is running, and no longer think of 'program' ...
Signals - Virtual Machine Model. System call interface {read(), write(), sigaltstack ... Fixed size resource table: ipc_perm structure plus type specific data ...
Provides both datagram and stream communication primitives/interfaces building ... Blocking data is streamed and kept in server queue: empty server queue causes ...
A Race Condition. Because of the timing and which process starts first ... Two (or more) processes are blocked waiting for an event that will never occur ...
int connect(int socket, struct sockaddr *destAddress, unsigned int addressLen) ... int send(int socket, const void *msg, unsigned int msgLen, int flags) ...
... passing, and sockets) that make it relatively easy for processes to communciate ... have a hierarchy, with one process effectively controlling or driving another ...
Functional: profession= professor , specialty= computer science) 23 ... Drawbacks (Weird) N points of failure. How to distinguish a dead participant from a refuse ...
forever; 6/21/09. B.Ramamurthy. 27. Solution for P/C using Semaphores ... forever; Ans: Consumer will busy-wait at the while statement. 6/21/09. B.Ramamurthy ...
The command 'ls | grep foo' creates two processes that communicate via a pipe ... The grep process reads on the read-end. An arbitrary number of pipes can be created: ...
Messages are directed and received from mailboxes (also referred to as ports) ... Buffered messages Mailboxes and Sockets. Sockets: Address Domain Port ...
... create a socket bound to an Internet address of the local host and a local port ... A client connects its socket to any free local port (at connect time) ...
Chapter 7 - Interprocess Communication Patterns. Why study IPC? Not typical programming style, but ... One interesting tidbit: readers & writers problem. ...
Both processes are started at the same time and consumer uses some old ... These 'functions' enclose the critical section. Ceng 334 - Operating Systems. 2.3-11 ...
Means of network IO. ... network address, port number etc. Communication style: stream , datagram, raw or ... Premature closing results in broken pipe ...
NOBLE: A Non-Blocking Inter-Process Communication Library. H kan ... Create a non-blocking inter-process communication interface that have these properties: ...
To understand the properties of processes and threads, and why threads are ... CPU between two processes: swapping CPU context, modifying registers of ...
the motivation for creating threads. the similarities and differences between processes and threads. ... Programmer specifies applications contain threads of execution ...
message passing - processes send and receive messages. Across address spaces ... IPC Message Passing. send ( ) operation. Synchronous. Returns after data is sent ...
Message Queues give you another way to send information from one task to another. ... One real bad characteristic: Msg Queues are based on a system buffer resource. ...
Race Conditions: two or more processes are reading and writing on shared data ... Mutual exclusion : making sure that if one process is ... Unlocked (0) ...