1.\" Copyright (c) 1980, 1991 Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)syscall.2 6.3 (Berkeley) 3/10/91 33.\" 34.Dd March 10, 1991 35.Dt SYSCALL 2 36.Os BSD 4 37.Sh NAME 38.Nm syscall 39.Nd indirect system call 40.Sh SYNOPSIS 41.Fd #include <unistd.h> 42.Fd #include <sys/syscall.h> 43.Ft int 44.Fn syscall "int number" "..." 45.Sh DESCRIPTION 46.Fn Syscall 47performs the system call whose assembly language 48interface has the specified 49.Fa number 50with the specified arguments. 51Symbolic constants for system calls can be found in the header file 52.Ao Pa syscall.h Ac . 53.Pp 54.Sh RETURN VALUES 55The r0 value of the system call is returned. 56When the C-bit is set, 57.Fn syscall 58returns -1 and sets the 59external variable 60.Va errno 61(see 62.Xr intro 2 ) . 63.Sh BUGS 64There is no way to simulate system calls 65such as 66.Xr pipe 2 . 67.Sh HISTORY 68The 69.Nm 70function call appeared in 71.Bx 4.0 . 72