System programming Notes and Examples ppt

System Notes and Examples

Mostly notes:

• What is a filter?
• Command Syntax.
• Make files.
• Include files, libraries, shared and dynamic libraries.
   
• System calls.
• What is a file?
• File I/O; Files and Directories.
• File Locking.
• Memory Mapped I/O.
• Process segments.
• File descriptors and open files (diagram in gif or pdf - See note below).
• Memory layout of C process (diagram in gif or pdf - See note below).
• Pipe, fork and exec and related process control topics, such as wait and job control.
• How a Bourne type shell does pipelines and lists (diagram in gif or pdf - See note below).
• FIFO - named pipes.
• Exit status as seen on a shell command.
• Executing shell commands from a C program.
• Signals including signal handlers and sigaction.
• Concurrency and operating systems.
• Threads:
  • Thread generalities and POSIX threads.
  • Kinds of threads (diagram in gif or pdf - See note below).
  • A simple POSIX threads example: pthreads.c. Use this makefile.
• A mini glossary.

Note: The gif files are faster and more convenient for viewing, but the pdf files gives better results if you wish to print the documents.Mostly examples:

• Determining some system limits.
• Determining maximum file name length.
• Seconds since epoch (1970 Jan 1).
• Big holes in files.
• Reading back through the stack.
• jobcntl.c is a program which job controls job (source job.c). Change the SRCDIR definition in jobctnl.c to suit. Make sure you have a console window open so you can read the trace messages. (On SUN's CDE use the workspace menu to open a console window; the window should have name ``console'' not ``terminal''.)
• sigmask.c shows how to mask a signal. All the the signal demos use reliable signalling, not signal( ).
• sigtmpfile.c shows how to remove a temporary file prior to an interupt, and also shows a library function that does something similar and is easier to use. Nevertheless, the function is not always what you want.
• sigmenu.c shows how a siglongjmp can be used with signals to abort from within some code. An editor might want to do something similar.
• ^D and EOF handling by terminal driver.
• ttyraw.c shows how to set the terminal into raw mode and have a read timer.