process(4) File Formats process(4)NAMEprocess - process contract type
SYNOPSIS
/system/contract/process
DESCRIPTION
Process contracts allow processes to create a fault boundary around a
set of subprocesses and observe events which occur within that bound‐
ary.
Process contracts are managed using the contract(4) file system and the
libcontract(3LIB) library. The process contract type directory is /sys‐
tem/contract/process.
CREATION
A process contract is created when an LWP that has an active process
contract template calls fork(2). Initially, the child process created
by fork() is the only resource managed by the contract. When an LWP
that does not have an active process contract template calls fork(),
the child process created by fork() is added as a resource to the
process contract of which the parent was a member.
EVENT TYPES
The following events types are defined:
CT_PR_EV_EMPTY
The last member of the process contract exited.
CT_PR_EV_FORK
A new process has been added to the process contract.
CT_PR_EV_EXIT
A member of the process contract exited.
CT_PR_EV_CORE
A process failed and dumped core. This could also occur if the
process would have dumped core had appropriate coreadm(1M) options
been enabled and core file size was unlimited.
CT_PR_EV_SIGNAL
A process received a fatal signal from a process, other than the
owner of the process contract, that is a member of a different
process contract.
CT_PR_EV_HWERR
A process was killed because of an uncorrectable hardware error.
TERMS
The following common contract terms, defined in contract(4), have
process-contract specific attributes:
informative event set
The default value for the informative event set is (CT_PR_EV_CORE |
CT_PR_EV_SIGNAL).
critical event set
The default value for the critical event set is (CT_PR_EV_EMPTY |
CT_PR_EV_HWERR).
An attempt by a user without the {PRIV_CONTRACT_EVENT} privilege in
its effective set to add an event, other than CT_PR_EV_EMPTY, to
the critical event set which is not present in the fatal set, or if
the CT_PR_PGONLY parameter is set and the same user attempts to add
any event, other than CT_PR_EV_EMPTY, to the critical event set,
fails.
The following contract terms can be read from or written to a process
contract template using the named libcontract(3LIB) interfaces. These
contract terms are in addition to those described in contract(4).
fatal event set
Defines a set of events which, when generated, causes all members
of the process contract to be killed with SIGKILL, or the intersec‐
tion of the contract and the containing process group if the
CT_PR_PGRPONLY parameter is set. Set this term with
ct_pr_tmpl_set_fatal(3CONTRACT). The fatal event set is restricted
to CT_PR_EV_CORE, CT_PR_EV_SIGNAL, and CT_PR_EV_HWERR. For
CT_PR_EV_CORE and CT_PR_EV_SIGNAL events, the scope of SIGKILL is
limited to those processes which the contract author or the event
source could have normally sent signals to.
The default value for the fatal event set is CT_PR_EV_HWERR.
If a user without the {PRIV_CONTRACT_EVENT} privilege in its effec‐
tive set removes an event from the fatal event set which is present
in the critical event set, the corresponding event is automatically
removed from the critical event set and added to the informative
event set.
parameter set
Defines miscellaneous other settings. Use
ct_pr_tmpl_set_param(3CONTRACT) to set this term.
The default parameter set is empty.
The value is a bit vector comprised of some or all of:
CT_PR_INHERIT
If set, indicates that the process contract is to be inherited
by the process contract the contract owner is a member of if
the contract owner exits before explicitly abandoning the
process contract.
If not set, the process contract is automatically abandoned
when the owner exits.
CT_PR_NOORPHAN
If set, all processes in a process contract are sent SIGKILL if
the process contract is abandoned, either explicitly or because
the holder died and CT_PR_INHERIT was not set. The scope of
SIGKILL is limited to those processes which the contract author
or the event source could have normally sent signals to.
If this is not set and the process contract is abandoned, the
process contract is orphaned, that is, continues to exist with‐
out owner.
CT_PR_PGRPONLY
If set, only those processes within the same process group and
process contract as a fatal error-generating process are
killed.
If not set, all processes within the process contract are
killed if a member process encounters an error specified in the
fatal set.
If a user without the {PRIV_CONTRACT_EVENT} privilege in its
effective set adds CT_PR_PGRPONLY to a template's parameter
set, any events other than CT_PR_EV_EMPTY are automatically
removed from the critical event set and added to the informa‐
tive event set.
CT_PR_REGENT
If set, the process contract can inherit unabandoned contracts
left by exiting member processes.
If not set, indicates that the process contract should not
inherit contracts from member processes. If a process exits
before abandoning a contract it owns and is a member of a
process contract which does not have CT_PR_REGENT set, the sys‐
tem automatically abandons the contract.
If a regent process contract has inherited contracts and is
abandoned by its owner, its inherited contracts are abandoned.
transfer contract
Specifies the ID of an empty process contract held by the caller
whose inherited process contracts are to be transferred to the
newly created contract. Use ct_pr_tmpl_set_transfer(3CONTRACT) to
set the tranfer contract. Attempts to specify a contract not held
by the calling process, or a contract which still has processes in
it, fail.
The default transfer term is 0, that is, no contract.
STATUS
In addition to the standard items, the status object read from a status
file descriptor contains the following items if CTD_FIXED is specified:
Fatal event set (term)
Parameter set (term)
Values equal to the terms used when the contract was written. Use
ct_pr_status_get_fatal(3contract)ct_pr_status_get_param(3contract)
to obtain this information. respectively.
If CTD_ALL is specified, the following items are also available:
Member list
The PIDs of processes which are members of the process contract.
Use ct_pr_status_get_members(3CONTRACT) to obtain this information.
Inherited contract list
The IDs of contracts which have been inherited by the process con‐
tract. Use ct_pr_status_get_contracts(3CONTRACT) to obtain this
information.
The following standard status items have different meanings in some
situations:
Ownership state
If the process contract has a state of CTS_OWNED or CTS_INHERITED
and is held by an entity in the global zone, but contains processes
in a non-global zone, it appears to have the state CTS_OWNED when
observed by processes in the non-global zone.
Contract holder
If the process contract has a state of CTS_OWNED or CTS_INHERITED
and is held by an entity in the global zone, but contains processes
in a non-global zone, it appears to be held by the non-global
zone's zsched when observed by processes in the non-global zone.
EVENTS
In addition to the standard items, an event generated by a process con‐
tract contains the following information:
Generating PID
The process ID of the member process which experienced the event,
or caused the contract event to be generated (in the case of
CT_PR_EV_EMPTY). Use ct_pr_event_get_pid(3CONTRACT) to obtain this
information.
If the event type is CT_PR_EV_FORK, the event contains:
Parent PID
The process ID which forked [Generating PID]. Use
ct_pr_event_get_ppid(3CONTRACT) to obtain this information.
If the event type is CT_PR_EV_EXIT, the event contains:
Exit status
The exit status of the process. Use ct_pr_event_get_exitsta‐
tus(3CONTRACT) to obtain this information.
If the event type is CT_PR_EV_CORE, the event can contain:
Process core name
The name of the per-process core file. Use ct_pr_event_get_pcore‐
file(3CONTRACT) to obtain this information.
Global core name
The name of the process's zone's global core file. Use
ct_pr_event_get_gcorefile(3CONTRACT) to obtain this information.
Zone core name
The name of the system-wide core file in the global zone. Use
ct_pr_event_get_zcorefile(3contract) to obtain this information.
See coreadm(1M) for more information about per-process, global, and
system-wide core files.
If the event type is CT_PR_EV_SIGNAL, the event contains:
Signal
The number of the signal which killed the process. Use
ct_pr_event_get_signal(3CONTRACT) to obtain this information.
It can contain:
sender
The PID of the process which sent the signal. Use
ct_pr_event_get_sender(3CONTRACT) to obtain this information.
FILES
/usr/include/sys/contract/process.h
Contains definitions of event-type macros.
SEE ALSOctrun(1), ctstat(1), ctwatch(1), coreadm(1M), close(2), fork(2),
ioctl(2), open(2), poll(2), ct_pr_event_get_exitstatus(3CONTRACT),
ct_pr_event_get_gcorefile(3CONTRACT), ct_pr_event_get_pcorefile(3CON‐
TRACT), ct_pr_event_get_pid(3CONTRACT), ct_pr_event_get_ppid(3CON‐
TRACT), ct_pr_event_get_signal(3CONTRACT), ct_pr_status_get_con‐
tracts(3CONTRACT), ct_pr_status_get_members(3CONTRACT),
ct_pr_tmpl_set_fatal(3CONTRACT), ct_pr_tmpl_set_param(3CONTRACT),
ct_pr_tmpl_set_transfer(3CONTRACT), ct_tmpl_set_cookie(3CONTRACT),
ct_tmpl_set_critical(3CONTRACT), ct_tmpl_set_informative(3CONTRACT),
libcontract(3LIB), contract(4), privileges(5)SunOS 5.10 9 Mar 2006 process(4)
