misc/54738: rump_server failed to bind

[edgar%pettijohn-web.com@localhost]

>Number:         54738
>Category:       misc
>Synopsis:       rump_server failed to bind
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    misc-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 05 02:10:00 +0000 2019
>Originator:     Edgar Pettijohn III
>Release:        9.99.19
>Organization:
>Environment:
NetBSD laptop.my.domain 9.99.19 NetBSD 9.99.19 (GENERIC) #0: Wed Dec  4 07:49:39 UTC 2019  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64

>Description:
Following along with https://www.netbsd.org/docs/rump/sptut.html specifically the Networking section I get the following:

laptop$ export RUMP_SERVER=unix://tmp/netsrv
laptop$ rump_server -lrumpnet -lrumpnet_net -lrumpnet_netinet -lrumpvfs -lrumpdev -lrumpdev_bpf -lrumpnet_virtif ${RUMP_SERVER}
[   1.0000000] pool redzone disabled for 'kmem-4096'
[   1.0000090] pool redzone disabled for 'buf64k'
rump_sp: failed to bind to URL unix://tmp/netsrv
rump server init failed: No such file or directory

>How-To-Repeat:
laptop$ export RUMP_SERVER=unix://tmp/netsrv
laptop$ rump_server -lrumpnet -lrumpnet_net -lrumpnet_netinet -lrumpvfs -lrumpdev -lrumpdev_bpf -lrumpnet_virtif ${RUMP_SERVER}
[   1.0000000] pool redzone disabled for 'kmem-4096'
[   1.0000090] pool redzone disabled for 'buf64k'
rump_sp: failed to bind to URL unix://tmp/netsrv
rump server init failed: No such file or directory

>Fix: