POOL_GET_PROPERTY(3POOL) Pool Configuration Manipulation Library Functions

NAME


pool_get_property, pool_put_property, pool_rm_property,
pool_walk_properties - resource pool element property manipulation

SYNOPSIS


cc [ flag... ] file... -lpool [ library... ]
#include <pool.h>

pool_value_class_t pool_get_property(pool_conf_t *conf,
const pool_elem_t *elem, const char *name,
pool_value_t *property);


int pool_put_property(pool_conf_t *conf, pool_elem_t *elem,
const char *name, const pool_value_t *value);


int pool_rm_property(pool_conf_t *conf, pool_elem_t *elem,
const char *name);


int pool_walk_properties(pool_conf_t *conf, pool_elem_t *elem,
void *arg, int (*callback)(pool_conf_t *, pool_elem_t *,
const char *, pool_value_t *, void *));


DESCRIPTION


The various pool types are converted to the common pool element type
(pool_elem_t) before property manipulation. A pool_value_t is an opaque
type that contains a property value of one of the following types:

POC_UINT
unsigned 64-bit integer


POC_INT
signed 64-bit integer


POC_DOUBLE
signed double-precision floating point value


POC_BOOL
boolean value: 0 is false, non-zero is true


POC_STRING
null-terminated string of characters


The conf argument for each function refers to the target configuration to
which the operation applies.


The pool_get_property() function attempts to retrieve the value of the
named property from the element. If the property is not found or an error
occurs, the value POC_INVAL is returned to indicate error. Otherwise the
type of the value retrieved is returned.


The pool_put_property() function attempts to set the named property on
the element to the specified value. Attempting to set a property that
does not currently exist on the element will cause the property with the
given name and value to be created on the element and will not cause an
error. An attempt to overwrite an existing property with a new property
of a different type is an error.


The pool_rm_property() function attempts to remove the named property
from the element. If the property does not exist or is not removable, -1
is returned and pool_error(3POOL) reports an error of POE_PUTPROP.


The pool_walk_properties() function invokes callback on all properties
defined for the given element. The callback is called with the element
itself, the name of the property, the value of the property, and the
caller-provided opaque argument.


A number of special properties are reserved for internal use and cannot
be set or removed. Attempting to do so will fail. These properties are
documented on the libpool(3LIB) manual page.

RETURN VALUES


Upon successful completion, pool_get_property() returns the type of the
property. Otherwise it returns POC_INVAL and pool_error() returns the
pool-specific error value.


Upon successful completion, pool_put_property(), pool_rm_property(), and
pool_walk_properties() return 0. Otherwise they return -1 and
pool_error() returns the pool-specific error value.

ERRORS


The pool_get_property() function will fail if:

POE_BADPARAM
The supplied configuration's status is not POF_VALID, the
supplied conf does not contain the supplied elem, or the
property is restricted and cannot be accessed by the
library.


POE_SYSTEM
A system error has occurred. Check the system error code
for more details.


The pool_put_property() function will fail if:

POE_BADPARAM
The supplied configuration's status is not POF_VALID,
the supplied conf does not contain the supplied elem,
the property name is not in the correct format, or
the property already exists and the supplied type
does not match the existing type.


POE_SYSTEM
A system error has occurred. Check the system error
code for more details.


POE_PUTPROP
The property name is reserved by libpool and not
available for use.


POE_INVALID_CONF
The configuration is invalid.


The pool_rm_property() function will fail if:

POE_BADPARAM
The supplied configuration's status is not POF_VALID, the
supplied conf does not contain the supplied elem, or the
property is reserved by libpool and cannot be removed.


POE_SYSTEM
A system error has occurred. Check the system error code
for more details.


POE_PUTPROP
The property name is reserved by libpool and not
available for use.


The pool_walk_properties() function will fail if:

POE_BADPARAM
The supplied configuration's status is not POF_VALID.


POE_SYSTEM
A system error has occurred. Check the system error code
for more details.


ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|CSI | Enabled |
+--------------------+-----------------+
|Interface Stability | Unstable |
+--------------------+-----------------+
|MT-Level | Safe |
+--------------------+-----------------+

SEE ALSO


libpool(3LIB), pool_error(3POOL), attributes(7)

May 16, 2020 POOL_GET_PROPERTY(3POOL)