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/* 05 Jun 93*/
/*
* mycall.c
*
* 05 Jun 93 Terry Lambert Split out of newsyscall.c
*
* Copyright (c) 1993 Terrence R. Lambert.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Terrence R. Lambert.
* 4. The name Terrence R. Lambert may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/param.h>
#include <sys/systm.h>
/* XXX this should be in a header. */
extern int mycall __P((struct proc *p, void *uap));
/*
* This is the actual code for the system call... it can't be static because
* it is exported to another part of the module... the only place it needs
* to be referenced is the sysent we are interested in.
*
* To write your own system call using this as a template, you could strip
* out this code and use the rest as a prototype module, changing only the
* function names and the number of arguments to the call in the module
* specific "sysent".
*
* You would have to use the "-R" option of "ld" to ensure a linkable file
* if you were to do this, since you would need to combine multiple ".o"
* files into a single ".o" file for use by "modload".
*/
int
mycall( p, uap)
struct proc *p;
void *uap;
{
/*
* Our new system call simply prints a message; it takes no
* arguments.
*/
printf( "\nI am a loaded system call.\n");
printf( "I was loaded using the syscall module loader interface.\n");
printf( "I don't do anything except call the kernel's printf().\n");
printf( "I will print this message each time I am called!\n");
return( 0); /* success (or error code from errno.h)*/
}
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