SYSCALL(2) SYSCALL(2)
NAME
syscall - indirect system call
SYNOPSIS
syscall(number, arg, ... ) (VAX)
syscall(number, r0, r1, arg ... ) (PDP11)
DESCRIPTION
Syscall performs the system call whose assembly language
interface has the specified number and arguments.
On a PDP11 the first two arguments correspond to registers
r0 and r1, regardless of whether the entry point really uses
them.
The r0 value of the system call is returned.
DIAGNOSTICS
When the C-bit is set, syscall returns -1 and sets the
external variable errno (see intro(2)).
BUGS
There is no way to simulate system calls such as pipe(2),
which return values in register r1.