ref: 5edeca01b0622463a65c126ebcc29314013fd928
dir: /man/2/drawmux/
.TH DRAWMUX 2 .SH NAME drawmux \- multiplex stream of draw requests .SH SYNOPSIS .EX include "drawmux.m"; drawmux := load Drawmux Drawmux->PATH; init: fn(): (string, ref Draw->Display); newviewer: fn(fd: ref Sys->FD); .EE .SH DESCRIPTION .B Drawmux puts itself between the invoking application and .B /dev/draw (see .IR draw (3)), so that the contents of the current display can be replicated elsewhere. .PP .B Init returns a new .B Display (see .IR draw-display (2)) representing a connection to a virtual display device. Subsequent .B Draw requests to that display (see .IR draw-intro (2)) are forwarded to the underlying .IR draw (3) device to appear on the physical display, but can also replicated elsewhere, typically in a window on a remote display. .PP .B Newviewer prepares the virtual display end of a .B Drawmux connection for each new viewer of the display created by a previous call to .BR init . The file descriptor .I fd is a connection to the viewer. The remote viewer must first write 24 bytes on that connection, containing two decimal numbers (each 11 digits and a space), giving the identifier of a public screen on the viewer's display, on which .B newviewer will replicate the .B Drawmux display, and the log (base 2) of the number of bits per pixel for windows created on that screen. The remote viewer must then use .B Sys->export (see .IR sys-export (2)) to export its .BR /dev/draw , which .B newviewer expects to find as the root of the exported hierarchy. Subsequent draw operations on the .B Drawmux display will be replicated on the public screen exported by the viewer. Shutting down the connection shuts down the multiplexor for that viewer. .SH SEE ALSO .IR wm-dmview (1), .IR draw-intro (2), .IR draw (3)