.TH MPXCALL 2
.SH NAME
mpxcall \- multiplexor and channel interface
.SH SYNOPSIS
.B mpxcall(arg1, arg2, arg3, cmd)
.SH DESCRIPTION
.I Mpxcall
supplies a primitive interface to the kernel
used by the routines listed below.
Each routine that uses
.I mpxcall
passes an integer
.I cmd
as the fourth argument.
These are defined in
.I /usr/include/mx.h.
.I Mpxcall
always returns an integer which is to be interpreted
in accordance with the definition of
.I cmd.
.SH "SEE ALSO"
group(2), join(2), extract(2), connect(2), chan(2), attach(2), detach(2)
.SH DIAGNOSTICS
The value \-1 is returned on error.