CS(8) CS(8)
NAME
cs, csquery - connection server
SYNOPSYS
lib/cs [ -f ] [ -v ]
svc/cs/cs [ -f ] [ -v ]
csquery [ -x net ] [ -s server ] [ address ... ]
DESCRIPTION
Cs spawns a process that serves a single file /net/cs, in
the current name space, answering requests by client pro-
cesses to translate symbolic network and service names into
instructions for connecting to the given service. It is
normally accessed by calls to sys-dial(2).
Each write to /net/cs is a network address of the same form
as the addr parameter to dial: network!netaddr!service where
service and network are optional. The write returns an
error if the address cannot be translated. Otherwise, each
subsequent read returns end-of-file (if there are no further
translations), or a translation of the form:
/net/net/clone address!port
The first field is the name of the clone file for a network
interface. To make a connection, open the file, and write
the text in the second field. There is a translation for
each network and for each network address on which a sym-
bolic netaddr is found. The file offset should be set to 0
using sys-seek(2) between the write and the read.
The file /net/cs persists until it is removed or unmounted
from /net, or the cs process is killed (see kill(1)). Nor-
mally only one instance of cs is active; if it finds, when
started, that /net/cs already exists, it prints a diagnostic
and exits. The -f option forces cs to put a new /net/cs
above the existing one in the current name space; subsequent
translation requests in the same name space will be resolved
by the new instance. The -v option causes cs to print each
translation request and results (if any) on standard error.
Cs is normally started once, before other applications
including srv(8). (On Plan 9, Plan 9's native connection
service will be used by default if Inferno's cs is not
started.) There are currently two versions: lib/cs is nor-
mally used on networked hosts with Ethernet access to a file
server; /svc/cs/cs must be used on small clients that use
PPP on a (dial-up) serial port for network access.
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CS(8) CS(8)
Csquery queries the given server (default: /net/cs) for a
translation of each address and prints the results, one per
line. If no address is given, csquery prompts for
address(es) to translate which it reads from the standard
input, printing the results of each translation on the stan-
dard output. The -x option gives an alternative mount point
for cs, when there is more than one network stack (see
ip(3)).
FILES
/services/cs/db map from symbolic service names to servers
/services/dns/db Internet addresses of DNS servers
SOURCE
/appl/lib/cs.b
/appl/svc/cs
SEE ALSO
sys-dial(2), db(6)
BUGS
To have two looks like carelessness.
Page 2 Plan 9 (printed 11/17/24)