Lecture Operating systems: Lesson 9 - Dr. Syed Mansoor Sarwar. The main topics covered in this lesson include: UNIX/Linux IPC tools and associated system calls, UNIX/Linux standard files and kernel’s mechanism for file access, use of pipe in a program and at the command line, . | Operating Systems Lecture 9 Agenda for Today Review of previous lecture UNIX Linux IPC tools and associated system calls UNIX Linux standard files and kernel s mechanism for file access Use of pipe in a program and at the command line Recap of the lecture 28 April 2022 Copyright Virtual University of Pakistan Review of Lecture 8 Interprocess communication IPC Establish link and use send recv Issues about links establishing links link capacity links per pair of processes processes per link message size uni- or bi-directional Direct communication Indirect communication 28 April 2022 Copyright Virtual University of Pakistan Review of Lecture 8 Process synchronization Buffering capacity of a link IPC in UNIX and Linux Pipe FIFO Socket etc. Per process file descriptor table pipe read write close system calls 28 April 2022 Copyright Virtual University of Pakistan UNIX Linux IPC Tools Pipe For communication between related processes on a system P1 P2 Pipe 28 April 2022 UNIX Linux System Copyright Virtual University of Pakistan UNIX Linux IPC Tools Named pipe FIFO For communication between unrelated processes on a system P1 P2 FIFO 28 April 2022 Copyright Virtual University of UNIX Linux System Pakistan UNIX Linux IPC Tools Socket For communication between unrelated processes on the same or different systems P1 P2 Network Socket Connection Socket 28Computer April 2022 1 Copyright Virtual University of Computer 2 Pakistan UNIX Linux Pipe Important system calls open read write close pipe open Open or create a file read Read from a pipe write Write data to a pipe close Close destroy a pipe pipe Create a pipe for IPC 28 April 2022 Copyright Virtual University of Pakistan open System Call include include include int open const char path int oflag mode_t mode . oflag specifies purpose of opening the file and mode specifies permission on the file if it is to be created. 28 April 2022 Copyright Virtual University of Pakistan open System Call Returns a file descriptor on success .
