.TH MPXCALL 2.SH NAMEmpxcall \- multiplexor and channel interface.SH SYNOPSIS.B mpxcall(arg1, arg2, arg3, cmd).SH DESCRIPTION.I Mpxcallsupplies a primitive interface to the kernelused by the routines listed below.Each routine that uses.I mpxcallpasses an integer.I cmdas the fourth argument.These are defined in.I /usr/include/mx.h..I Mpxcallalways returns an integer which is to be interpretedin 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 DIAGNOSTICSThe value \-1 is returned on error.