Menu
I'm trying to figure out how to get a list of and documentation for the system calls available in the XNU kernel in OSX. I've googled around quite a bit, but haven't been able to find anything of use. As I understand the calling conventions match BSD, is that correct?
Thanks
812
A system call is a way for programs to interact with the operating system. A computer program makes a system call when it makes a request to the operating system's kernel. System call provides the services of the operating system to the user programs via Application Program Interface(API).
The kernel doesn't monitor the process to detect a system call. Instead, the process generates an interrupt which transfers control to the kernel, because that's what software-generated interrupts do according to the instruction set reference manual.
System calls are the most critical interface of all user space software. They are the means of invoking kernel's functionality. Without them, software would not be able to communicate with the user, access the file system or establish network connections.
A system call is a programmatic way a program requests a service from the kernel, and strace is a powerful tool that allows you to trace the thin layer between user processes and the Linux kernel. To understand how an operating system works, you first need to understand how system calls work.
The "official" list is at Darwin page at Apple. Specifically, see the file syscalls.master in the XNU distribution. (If something you expect is missing, try a newer XNU version.)
The BSD part of the system calls comes from BSD, but there're mach calls which follow quite different conventions.
You'll definitely want to read Amit Singh's OS X kernel book, see the book's website. It's rewritten for 10.4 and mainly for PPC, but still is the greatest detailed info you can get on the kernel.
112
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
