Subject: Re: how to use syscalls
To: Robin Kumar <>
From: Manuel Bouyer <>
List: tech-kern
Date: 06/25/2000 21:36:17
On Sun, Jun 25, 2000 at 11:48:29AM -0700, Robin Kumar wrote:
> I was trying to add a system call to NetBSD 1.4.1.
> What i have done is added the entries in
> syscalls.master and some other syscall files. I have
> added code for syscall in xyz.c.It is has been
> compiled 
> also, but the problem is i do not know how can i
> use it from a user process.	
> 	What has to be done to call it from a C
> programme.Please answer in detail as i donot know
> anything about it.I want to mention one more thing
> that
> i do not have /usr/src/lib rather i have
> /usr/src/sys/lib.

Ok, you've done the kernel part now you need to add your syscall to libc.
Grab from
and untar it (I suspect you've only the kernel sources installed).
Then you'll have the libc sources in /usr/src/lib/libc. Add you syscall here,
and recompile/reinstall libc.

>    Is ther any other way like in Linux,one can use
> standard macros in C programme to call a system call.

I don't know much about linux, but I suspect in NetBSD this is all
hidden in libc.

Manuel Bouyer <>