1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 2001 Alexander Langer 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd January 24, 2015 32.Dt SYSCALL_MODULE 9 33.Os 34.Sh NAME 35.Nm SYSCALL_MODULE 36.Nd syscall kernel module declaration macro 37.Sh SYNOPSIS 38.In sys/param.h 39.In sys/kernel.h 40.In sys/proc.h 41.In sys/module.h 42.In sys/sysent.h 43.Fn SYSCALL_MODULE name "int *offset" "struct sysent *new_sysent" "modeventhand_t evh" "void *arg" 44.Sh DESCRIPTION 45The 46.Fn SYSCALL_MODULE 47macro declares a new syscall. 48.Fn SYSCALL_MODULE 49expands into a kernel module declaration with name 50.Ql sys/ Ns Fa name . 51.Pp 52The rest of the arguments expected by this macro are: 53.Bl -tag -width ".Fa new_sysent" 54.It Fa offset 55A pointer to an 56.Vt int 57which saves the offset in 58.Vt "struct sysent" 59where the syscall is allocated. 60If the location pointed to by 61.Fa offset 62holds a non 0 number it will be used if possible. 63If it holds 0 then one will be assigned. 64.It Fa new_sysent 65is a pointer to a structure that specifies the function implementing 66the syscall and the number of arguments this function needs (see 67.In sys/sysent.h ) . 68.It Fa evh 69A pointer to the kernel module event handler function with the argument 70.Fa arg . 71Please refer to 72.Xr module 9 73for more information. 74.It Fa arg 75The argument passed to the callback functions of the 76.Fa evh 77event handler when it is called. 78.El 79.Pp 80The syscall number assigned to the module can be retrieved using the 81.Xr modstat 3 82and 83.Xr modfind 3 84library functions in libc. 85The MACRO 86.Fn SYSCALL_MODULE_HELPER 87includes 88.Fn SYSCALL_MODULE 89and much of its boilerplate code. 90.Sh EXAMPLES 91A minimal example for a syscall module can be found in 92.Pa /usr/share/examples/kld/syscall/module/syscall.c . 93.Sh SEE ALSO 94.Xr module 9 95.Pp 96.Pa /usr/share/examples/kld/syscall/module/syscall.c 97.Sh AUTHORS 98This manual page was written by 99.An Alexander Langer Aq Mt alex@FreeBSD.org . 100