rctlblk_set_value(3C) Standard C Library Functions rctlblk_set_value(3C)NAME
rctlblk_set_value, rctlblk_get_firing_time, rctlblk_get_global_action,
rctlblk_get_global_flags, rctlblk_get_local_action, rctl‐
blk_get_local_flags, rctlblk_get_privilege, rctlblk_get_recipient_pid,
rctlblk_get_value, rctlblk_get_enforced_value, rctl‐
blk_set_local_action, rctlblk_set_local_flags, rctlblk_set_privilege,
rctlblk_set_recipient_pid, rctlblk_size - manipulate resource control
blocks
SYNOPSIS
#include <rctl.h>
hrtime_t rctlblk_get_firing_time(rctlblk_t *rblk);
int rctlblk_get_global_action(rctlblk_t *rblk);
int rctlblk_get_global_flags(rctlblk_t *rblk);
int rctlblk_get_local_action(rctlblk_t *rblk, int *signalp);
int rctlblk_get_local_flags(rctlblk_t *rblk);
rctl_priv_t rctlblk_get_privilege(rctlblk_t *rblk);
id_t rctlblk_get_recipient_pid(rctlblk_t *rblk);
rctl_qty_t rctlblk_get_value(rctlblk_t *rblk);
rctl_qty_t rctlblk_get_enforced_value(rctlblk_t *rblk);
void rctlblk_set_local_action(rctlblk_t *rblk, rctl_action_t action,
int signal);
void rctlblk_set_local_flags(rctlblk_t *rblk, int flags);
void rctlblk_set_privilege(rctlblk_t *rblk, rctl_priv_t privilege);
void rctlblk_set_value(rctlblk_t *rblk, rctl_qty_t value);
void rctlblk_set_recipient_pid(id_tpid);
size_t rctlblk_size(void);
DESCRIPTION
The resource control block routines allow the establishment or
retrieval of values from a resource control block used to transfer
information using the getrctl(2) and setrctl(2) functions. Each of the
routines accesses or sets the resource control block member correspond‐
ing to its name. Certain of these members are read-only and do not
possess set routines.
The firing time of a resource control block is 0 if the resource con‐
trol action-value has not been exceeded for its lifetime on the
process. Otherwise the firing time is the value of gethrtime(3C) at
the moment the action on the resource control value was taken.
The global actions and flags are the action and flags set by rct‐
ladm(1M). These values cannot be set with setrctl(2). Valid global
actions are listed in the table below. Global flags are generally a
published property of the control and are not modifiable.
RCTL_GLOBAL_DENY_ALWAYS
The action taken when a control value is exceeded on this control
will always include denial of the resource.
RCTL_GLOBAL_DENY_NEVER
The action taken when a control value is exceeded on this control
will always exclude denial of the resource; the resource will
always be granted, although other actions can also be taken.
RCTL_GLOBAL_SIGNAL_NEVER
No signal actions are permitted on this control.
RCTL_GLOBAL_CPU_TIME
The valid signals available as local actions include the SIGXCPU
signal.
RCTL_GLOBAL_FILE_SIZE
The valid signals available as local actions include the SIGXFSZ
signal.
RCTL_GLOBAL_INFINITE
This resource control supports the concept of an unlimited value;
generally true only of accumulation-oriented resources, such as CPU
time.
RCTL_GLOBAL_LOWERABLE
Non-privileged callers are able to lower the value of privileged
resource control values on this control.
RCTL_GLOBAL_NOACTION
No global action will be taken when a resource control value is
exceeded on this control.
RCTL_GLOBAL_NOBASIC
No values with the RCPRIV_BASIC privilege are permitted on this
control.
RCTL_GLOBAL_SYSLOG
A standard message will be logged by the syslog(3C) facility when
any resource control value on a sequence associated with this con‐
trol is exceeded.
RCTL_GLOBAL_UNOBSERVABLE
The resource control (generally on a task- or project-related con‐
trol) does not support observational control values. An
RCPRIV_BASIC privileged control value placed by a process on the
task or process will generate an action only if the value is
exceeded by that process.
RCTL_GLOBAL_BYTES
This resource control represents a number of bytes.
RCTL_GLOBAL_SECONDS
This resource control represents a quantity of time in seconds.
RCTL_GLOBAL_COUNT
This resource control represents an integer count.
The local action and flags are those on the current resource control
value represented by this resource control block. Valid actions and
flags are listed in the table below. In the case of RCTL_LOCAL_SIGNAL,
the second argument to rctlblk_set_local_action() contains the signal
to be sent. Similarly, the signal to be sent is copied into the integer
location specified by the second argument to rctl‐
blk_get_local_action(). A restricted set of signals is made available
for normal use by the resource control facility: SIGBART, SIGXRES,
SIGHUP, SIGSTOP, SIGTERM, and SIGKILL. Other signals are permitted due
to global properties of a specific control. Calls to setrctl() with
illegal signals will fail.
RCTL_LOCAL_DENY
When this resource control value is encountered, the request for
the resource will be denied. Set on all values if
RCTL_GLOBAL_DENY_ALWAYS is set for this control; cleared on all
values if RCTL_GLOBAL_DENY_NEVER is set for this control.
RCTL_LOCAL_MAXIMAL
This resource control value represents a request for the maximum
amount of resource for this control. If RCTL_GLOBAL_INFINITE is set
for this resource control, RCTL_LOCAL_MAXIMAL indicates an unlim‐
ited resource control value, one that will never be exceeded.
RCTL_LOCAL_NOACTION
No local action will be taken when this resource control value is
exceeded.
RCTL_LOCAL_SIGNAL
The specified signal, sent by rctlblk_set_local_action(), will be
sent to the process that placed this resource control value in the
value sequence. This behavior is also true for signal actions on
project and task resource controls. The specified signal is sent
only to the recipient process, not all processes within the project
or task.
The rctlblk_get_recipient_pid() function returns the value of the
process ID that placed the resource control value for basic rctls. For
privileged or system rctls, rctlblk_get_recipient_pid() returns -1.
The rctlblk_set_recipient_pid() function sets the recipient pid for a
basic rctl. When setrctl(2) is called with the flag RCTL_USE_RECIPI‐
ENT_PID, this pid is used. Otherwise, the PID of the calling process is
used. Only privileged users can set the recipient PID to one other than
the PID of the calling process. Process-scoped rctls must have a
recipient PID that matches the PID of the calling process.
The rctlblk_get_privilege() function returns the privilege of the
resource control block. Valid privileges are RCPRIV_BASIC, RCPRIV_PRIV‐
ILEGED, and RCPRIV_SYSTEM. System resource controls are read-only.
Privileged resource controls require the {PRIV_SYS_RESOURCE} privilege
to write, unless the RCTL_GLOBAL_LOWERABLE global flag is set, in which
case unprivileged applications can lower the value of a privileged con‐
trol.
The rctlblk_get_value() and rctlblk_set_value() functions return or
establish the enforced value associated with the resource control. In
cases where the process, task, or project associated with the control
possesses fewer capabilities than allowable by the current value, the
value returned by rctlblk_get_enforced_value() will differ from that
returned by rctlblk_get_value(). This capability difference arises with
processes using an address space model smaller than the maximum address
space model supported by the system.
The rctlblk_size() function returns the size of a resource control
block for use in memory allocation. The rctlblk_t * type is an opaque
pointer whose size is not connected with that of the resource control
block itself. Use of rctlblk_size() is illustrated in the example
below.
RETURN VALUES
The various set routines have no return values. Incorrectly composed
resource control blocks will generate errors when used with setrctl(2)
or getrctl(2).
ERRORS
No error values are returned. Incorrectly constructed resource control
blocks will be rejected by the system calls.
EXAMPLES
Example 1: Display the contents of a fetched resource control block.
The following example displays the contents of a fetched resource con‐
trol block.
#include <rctl.h>
#include <stdio.h>
#include <stdlib.h>
rctlblk_t *rblk;
int rsignal;
int raction;
if ((rblk = malloc(rctlblk_size())) == NULL) {
(void) perror("rblk malloc");
exit(1);
}
if (getrctl("process.max-cpu-time", NULL, rblk, RCTL_FIRST) == -1) {
(void) perror("getrctl");
exit(1);
}
main()
{
raction = rctlblk_get_local_action(rblk, &rsignal),
(void) printf("Resource control for %s\n",
"process.max-cpu-time");
(void) printf("Process ID: %d\n",
rctlblk_get_recipient_pid(rblk));
(void) printf("Privilege: %x\n"
rctlblk_get_privilege(rblk));
(void) printf("Global flags: %x\n"
rctlblk_get_global_flags(rblk));
(void) printf("Global actions: %x\n"
rctlblk_get_global_action(rblk));
(void) printf("Local flags: %x\n"
rctlblk_get_local_flags(rblk));
(void) printf("Local action: %x (%d)\n"
raction, raction == RCTL_LOCAL_SIGNAL ? rsignal : 0);
(void) printf("Value: %llu\n",
rctlblk_get_value(rblk));
(void) printf("Enforced value: %llu\n",
rctlblk_get_enforced_value(rblk));
}
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Evolving │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOrctladm(1M), getrctl(2), setrctl(2), gethrtime(3C), attributes(5)SunOS 5.10 22 Mar 2004 rctlblk_set_value(3C)
