SRV9(3) (Plan 9) SRV9(3) NAME srv9 - plan 9 server registry SYNOPSIS bind -c #₪ /srv /srv/service1 /srv/service2 ... DESCRIPTION On Inferno hosted on Plan 9, srv9 serves a one-level direc- tory that gives Inferno applications direct access to Plan 9 services posted in its #s server registry, and allows Inferno applications to post services for access by Plan 9 applications. A service is represented by a file descrip- tor, usually serving the common file service protocol described in intro(5), allowing it to be mounted (see bind(1) and sys-bind(2)) in the name space of an application in the other system. To access a Plan 9 service in Inferno, open the desired ser- vice file; the resulting file descriptor is connected to the associated Plan 9 service. When that service is a shared Plan 9 file service, srv9 automatically starts Plan 9's exportfs with appropriate options to make the service acces- sible from Inferno. It can safely be shared with Plan 9 applications, but note that any path names mentioned in the attach specifier (see mount(1) and attach(5)) will be in the Plan 9 application's name space, not the Inferno application's. (Indeed, a similar caveat applies in Plan 9 itself.) To export an Inferno service to Plan 9, create a new file such as /srv/myserv using Sys->create with mode Sys->ORDWR (see sys-open(2)) and any desired permissions for the new service file. (Note that the #₪ device must have been bound in with the -c option, as shown above, to allow file cre- ation.) If the create is successful, Plan 9's service reg- istry will have a new entry myserv, and the file descriptor returned from create acts as a pipe to any Plan 9 applica- tion that opens the associated service file in Plan 9. Typ- ically on the Inferno side the file descriptor is passed to sys-export(2) or made the standard input of an Inferno file service (see intro(4)). The Plan 9 service file is automati- cally removed when the Inferno file descriptor is no longer referenced. EXAMPLES To make Plan 9's factotum available in Inferno: Page 1 Plan 9 (printed 9/8/24) SRV9(3) (Plan 9) SRV9(3) mount -Aa /srv/factotum /mnt (Note the -A option to suppress Inferno authentication.) To mount the Plan 9 file service from which a Plan 9 machine booted: mount -9 /srv/boot /n/local The -9 option to mount(1) requests Plan 9 authentication; that could also have been used instead of -A in the previous example. To make the environment variables of the current Inferno name space available to Plan 9: fd := sys->create("/srv/infenv", Sys->ORDWR, 8r600); sys->export(fd, "/env", Sys->EXPWAIT); SOURCE /emu/Plan9/devsrv9.c SEE ALSO sys-bind(2), sys-open(2), sys-export(2), import(4), 9srvfs(4) Page 2 Plan 9 (printed 9/8/24)