contract(4) File Formats contract(4)NAMEcontract - the contract file system
SYNOPSIS
/system/contract
DESCRIPTION
The /system/contract file system acts as the primary interface to the
contract subsystem. There is a subdirectory of /system/contract for
each available contract type.
/system/contract can be mounted on any mount point, in addition to the
standard /system/contract mount point, and can be mounted several
places at once. Such additional mounts are allowed in order to facili‐
tate the confinement of processes to subtrees of the file system using
chroot(1M) and yet allow such processes to continue to use contract
commands and interfaces.
A combination of standard system calls (for example, open(2), close(2),
and poll(2)) and calls to libcontract(3LIB) access /system/contract
files.
Consumers of the contract file system must be large file aware. See
largefile(5) and lfcompile64(5).
DIRECTORY STRUCTURE
At the top level, the /system/contract directory contains subdirecto‐
ries named with each available contract type, and one special direc‐
tory, all. Each of these directories is world-readable and world-
searchable.
STRUCTURE OF /system/contract/type
Each /system/contract/type directory contains a fixed number of files.
It also contains a variable number of subdirectories corresponding to
existing contracts of type type and named with the decimal representa‐
tion of the contracts' IDs.
The following files are in a /system/contract/type directory:
template Opening this file returns a file descriptor for a new type
contract template.
You can use the following libcontract(3LIB) calls on a tem‐
plate file descriptor:
>
ct_tmpl_activate(3contract)ct_tmpl_clear(3contract)ct_tmpl_create(3contract)
See TERMS for additional template functions.
latest Opening this file returns a file descriptor for the status
file of the last type contract written by the opening LWP.
See STRUCTURE OF /system/contract/type/id. If the opening
LWP has not created a type contract, opening latest fails
with ESRCH.
bundle Opening this file returns a file descriptor for an event
endpoint which receives events from all type contracts on
the system. No privileges are required to open a type bun‐
dle event endpoint. Events sent by contracts owned and
written by users other than the reader's effective user id
are invisible, that is, they are silently skipped, unless
the reader has {PRIV_CONTRACT_OBSERVER} in its effective
set. See EVENTS.
pbundle Opening this file returns a file descriptor for an event
endpoint which receives events from all type contracts held
by the opening process. See EVENTS.
STRUCTURE OF /system/contract/all
The /system/contract/all directory contains a numerically named file
for each contract in the system. Each file is a symbolic link to the
type-specific directory for that contract, that is /system/con‐
tract/all/id points to /system/contract/type/id.
STRUCTURE OF /system/contract/type/id
Each /system/contract/type/id directory contains the following files:
ctl Opening this file returns a file descriptor for contract id's
control file. The open fails if the opening process does not
hold contract id and the contract has not been inherited by
the process contract of which the opening process is a mem‐
ber. See process(4).
The following libcontract(3LIB) calls can be made on a ctl
file descriptor if the contract is owned by the caller:
ct_ctl_abandon(3contract)ct_ctl_newct(3contract)ct_ctl_ack(3contract)ct_ctl_qack(3contract)
The following libcontract(3LIB) call can be made on a ctl
file descriptor if the contract doesn't have an owner:
ct_ctl_adopt(3contract)
status Opening this file returns a file descriptor for contract id's
status file. The following libcontract(3LIB) calls can be
made on a status file descriptor:
ct_status_read(3contract)
See STATUS.
events Opening this file returns a file descriptor for an event end‐
point which receives events from contract id. See EVENTS.
Only a process which has the same effective user ID as the
process owning the contract, the same effective user ID as
the contract's author, or has {PRIV_CONTRACT_OBSERVER} in its
effective set can open the event endpoint for a contract.
TERMS
The following terms are defined for all contracts:
cookie Specifies a 64-bit quantity that the contract
author can use to identify the contract. Use
ct_tmpl_set_cookie(3CONTRACT) to set this
term.
informative event set Selects which events are delivered as informa‐
tive events. Use ct_tmpl_set_informative(3CON‐
TRACT) to set this term.
critical event set Selects which events are delivered as critical
events. Use ct_tmpl_set_critical(3CONTRACT) to
set this term.
STATUS
A status object returned by ct_status_read(3CONTRACT) contains the fol‐
lowing pieces of information:
contract ID
The numeric ID of the contract. Use ct_status_get_id(3CONTRACT) to
obtain this information.
contract type
The type of the contract, specifed as a string. Obtained using
ct_status_get_type(3CONTRACT). The contract type is the same as its
subdirectory name under /system/contract.
creator's zone ID
The zone ID of the process which created the contract. Obtained
using ct_status_get_zoneid(3CONTRACT).
ownership state
The state of the contract, specified as CTS_OWNED, CTS_INHERITED,
CTS_ORPHAN, or CTS_DEAD. Use ct_status_get_state(3CONTRACT) to
obtain this information.
contract holder
If the contract's state is CTS_OWNED, the ID of the process which
owns the contract. If the contract's state is CTS_INHERITED, the ID
of the contract which is acting as regent. If the contract's state
is CTS_ORPHAN or CTS_DEAD, this is undefined. Use ct_sta‐
tus_get_holder(3CONTRACT) to obtain this information.
number of critical events
The number of unacknowledged critical events pending on the con‐
tract's event queue. Use ct_status_get_nevents(3CONTRACT) to obtain
this information.
negotiation time
The time remaining before the current synchronous negotiation times
out. Use ct_status_get_ntime(3CONTRACT) to obtain this information.
negotiation quantum time
The time remaining before the current negotiation quantum runs out.
Use ct_status_get_qtime(3CONTRACT) to obtain this information.
negotiation event ID
The ID of the event which initiated the negotiation timeout. Use
ct_status_get_nevid(3CONTRACT) to obtain this information.
cookie (term)
The contract's cookie term. Use ct_status_get_cookie(3CONTRACT) to
obtain this information.
Informative event set (term)
The contract's informative event set. Use ct_status_get_informa‐
tive(3CONTRACT) to obtain this information.
Critical event set (term)
The contract's critical event set. Use ct_status_get_critical(3CON‐
TRACT) to obtain this information.
EVENTS
All three event endpoints, /system/contract/type/bundle, /system/con‐
tract/type/pbundle, and /system/contract/type/id/events, are accessed
in the same manner.
The following libcontract(3LIB) interfaces are used with an event end‐
point file descriptor:
ct_event_read(3contract)ct_event_read_critical(3contract)ct_event_reset(3contract)ct_event_next(3contract)
To facilitate processes watching multiple event endpoints, it is possi‐
ble to poll(2) on event endpoints. When it is possible to receive on an
endpoint file descriptor, POLLIN is set for that descriptor.
An event object returned by ct_event_read(3CONTRACT) contains the fol‐
lowing information:
contract ID The ID of the contract that generated the
event. Use ct_event_read(3CONTRACT) to
obtain this information.
event ID The ID of the contract event.Use
ct_event_get_evid(3CONTRACT).
flags A bit vector possibly including CT_ACK and
CTE_INFO. Use ct_event_get_flags(3CONTRACT)
to obtain this information.
event type The type of event, equal to one of the con‐
stants specified in the contract type's
manual page or CT_EV_NEGEND. Use
ct_event_get_type(3CONTRACT) to obtain this
information.
EVENT TYPES
The following event types are defined:
CT_EV_NEGEND Some time after an exit negotiation is initiated, the
CT_EV_NEGEND event is sent. This indicates that the
negotiation ended. This might be because the operation
was cancelled, or because the operation was successful.
If successful, and the owner requested that a new con‐
tract be written, this contains the ID of that con‐
tract.
CT_EV_NEGEND cannot be included in a contract's infor‐
mative or critical event set. It is always delivered
and always critical. If CT_EV_NEGEND indicates that the
operation was successful, no further events are sent.
The contract's owner should use ct_ctl_abandon(3CON‐
TRACT) to abandon the contract.
A CT_EV_NEGEND event contains:
negotiation ID The ID of the negotiation which
ended. Use ct_event_get_nevid(3CON‐
TRACT) to obain this information.
new contract ID The ID of the newly created con‐
tract. This value is 0 if no con‐
tract was created, or the ID of the
existing contract if the operation
was not completed. Use
ct_event_get_newct(3CONTRACT) to
obtain this information.
FILES
/system/contract
List of all contract types
/system/contract/all
Directory of all contract IDs
/system/contract/all/id
Symbolic link to the type-specific directory of contract id
/system/contract/type
Specific type directory
/system/contract/type/templete
Template for the contract type
/system/contract/type/bundle
Listening point for all contracts of that type
/system/contract/type/pbundle
Listening point for all contracts of that type for the opening
process
/system/contract/type /latest
Status of most recent type contract created by the opening LWP
/system/contract/type/ID
Directory for contract id
/system/contract/type/ID/events
Listening point for contract id's events
/system/contract/type/ID/ctl
Control file for contract ID
/system/contract/type/ID/status
Status info for contract ID
SEE ALSOctrun(1), ctstat(1), ctwatch(1), chroot(1M), close(2), ioctl(2),
open(2), poll(2), ct_ctl_abandon(3CONTRACT), ct_event_read(3CONTRACT),
ct_event_get_evid(3CONTRACT), ct_event_get_flags(3CONTRACT),
ct_event_get_nevid(3CONTRACT), ct_event_get_newct(3CONTRACT),
ct_event_get_type(3CONTRACT), ct_status_read(3CONTRACT)ct_sta‐
tus_get_cookie(3CONTRACT), ct_status_get_critical(3CONTRACT), ct_sta‐
tus_get_holder(3CONTRACT), ct_status_get_id(3CONTRACT), ct_sta‐
tus_get_informative(3CONTRACT), ct_status_get_nevid(3CONTRACT), ct_sta‐
tus_get_nevents(3CONTRACT), ct_status_get_ntime(3CONTRACT), ct_sta‐
tus_get_qtime(3CONTRACT), ct_status_get_state(3CONTRACT), ct_sta‐
tus_get_type(3CONTRACT), ct_tmpl_set_cookie(3CONTRACT),
ct_tmpl_set_critical(3CONTRACT), ct_tmpl_set_informative(3CONTRACT),
libcontract(3LIB), process(4), largefile(5), lfcompile(5), privi‐
leges(5)SunOS 5.11 11 Jul 2005 contract(4)
