System Calls

System Calls for Process Management

• load
• execute
• end, abort
• create process (for example, fork on Unix-like systems, or
• tCreateProcess in the Windows NT Native API)
• terminate process
• get/set process attributes
• wait for time, wait event, signal event
• allocate, free memory

System Calls for File Management

• create file, delete file
• open, close
• read, write, reposition
• get/set file attributes

System Calls for Directory Management

• mkdir
• rmdir
• link
• mount

Miscellaneous System Calls

• chdir
• chmod
• kill
• time

The Windows Win32 API

The key here is that, unlike POSIX, Microsoft has decoupled system calls and library routines. While POSIX system calls number about 100, Win32 has thousands of API calls.

Charles Petzold: "The original hello world program in the Windows 1.0 SDK was a bit of a scandal. HELLO.C was about 150 lines long, and the HELLO.RC resource script had another 20 or so more lines... Veteran programmers often curled up in horror or laughter when encountering the Windows hello-world program."[18]

External Links

• System call
  (Some of the above material is drawn from this article.)
• POSIX
• Windows API