xref: /netbsd-src/lib/libc/sys/syscall.2 (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
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32.\"     from: @(#)syscall.2	6.3 (Berkeley) 3/10/91
33.\"	$Id: syscall.2,v 1.3 1993/11/25 00:39:55 jtc Exp $
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35.Dd March 10, 1991
36.Dt SYSCALL 2
37.Os BSD 4
38.Sh NAME
39.Nm syscall
40.Nd indirect system call
41.Sh SYNOPSIS
42.Fd #include <unistd.h>
43.Fd #include <sys/syscall.h>
44.Ft int
45.Fn syscall "int number" "..."
46.Sh DESCRIPTION
47.Fn Syscall
48performs the system call whose assembly language
49interface has the specified
50.Fa number
51with the specified arguments.
52Symbolic constants for system calls can be found in the header file
53.Ao Pa syscall.h Ac .
54.Pp
55.Sh RETURN VALUES
56The r0 value of the system call is returned.
57When the C-bit is set,
58.Fn syscall
59returns -1 and sets the
60external variable
61.Va errno
62(see
63.Xr intro 2 ) .
64.Sh BUGS
65There is no way to simulate system calls
66such as
67.Xr pipe 2 .
68.Sh HISTORY
69The
70.Fn syscall
71function call appeared in
72.Bx 4.0 .
73