NVLIST_LOOKUP_BOOLEAN(3NVPAIR) Name-value Pair Library Functions

NAME


nvlist_lookup_boolean, nvlist_lookup_boolean_value,
nvlist_lookup_byte, nvlist_lookup_int8, nvlist_lookup_uint8,
nvlist_lookup_int16, nvlist_lookup_uint16, nvlist_lookup_int32,
nvlist_lookup_uint32, nvlist_lookup_int64, nvlist_lookup_uint64,
nvlist_lookup_double, nvlist_lookup_string, nvlist_lookup_nvlist,
nvlist_lookup_boolean_array, nvlist_lookup_byte_array,
nvlist_lookup_int8_array, nvlist_lookup_uint8_array,
nvlist_lookup_int16_array, nvlist_lookup_uint16_array,
nvlist_lookup_int32_array, nvlist_lookup_uint32_array,
nvlist_lookup_int64_array, nvlist_lookup_uint64_array,
nvlist_lookup_nvlist_array, nvlist_lookup_string_array,
nvlist_lookup_pairs - match name and type indicated by the interface
name and retrieve data value

SYNOPSIS


cc [ flag... ] file... -lnvpair [ library... ]
#include <libnvpair.h>

int nvlist_lookup_boolean(nvlist_t *nvl, const char *name);


int nvlist_lookup_boolean_value(nvlist_t *nvl,
const char *name, boolean_t *val);


int nvlist_lookup_byte(nvlist_t *nvl, const char *name,
uchar_t *val);


int nvlist_lookup_int8(nvlist_t *nvl, const char *name,
int8_t *val);


int nvlist_lookup_uint8(nvlist_t *nvl, const char *name,
uint8_t *val);


int nvlist_lookup_int16(nvlist_t *nvl, const char *name,
int16_t *val);


int nvlist_lookup_uint16(nvlist_t *nvl, const char *name,
uint16_t *val);


int nvlist_lookup_int32(nvlist_t *nvl, const char *name,
int32_t *val);


int nvlist_lookup_uint32(nvlist_t *nvl, const char *name,
uint32_t *val);


int nvlist_lookup_int64(nvlist_t *nvl, const char *name,
int64_t *val);


int nvlist_lookup_uint64(nvlist_t *nvl, const char *name,
uint64_t *val);


int nvlist_lookup_double(nvlist_t *nvl, const char *name,
double *val);


int nvlist_lookup_string(nvlist_t *nvl, const char *name,
char **val);


int nvlist_lookup_nvlist(nvlist_t *nvl, const char *name,
nvlist_t **val);


int nvlist_lookup_boolean_array(nvlist_t *nvl, const char *name,
boolean_t **val, uint_t *nelem);


int nvlist_lookup_byte_array(nvlist_t *nvl, const char *name,
uchar_t **val, uint_t *nelem);


int nvlist_lookup_int8_array(nvlist_t *nvl, const char *name,
int8_t **val, uint_t *nelem);


int nvlist_lookup_uint8_array(nvlist_t *nvl, const char *name,
uint8_t **val, uint_t *nelem);


int nvlist_lookup_int16_array(nvlist_t *nvl, const char *name,
int16_t **val, uint_t *nelem);


int nvlist_lookup_uint16_array(nvlist_t *nvl, const char *name,
uint16_t **val, uint_t *nelem);


int nvlist_lookup_int32_array(nvlist_t *nvl, const char *name,
int32_t **val, uint_t *nelem);


int nvlist_lookup_uint32_array(nvlist_t *nvl, const char *name,
uint32_t **val, uint_t *nelem);


int nvlist_lookup_int64_array(nvlist_t *nvl, const char *name,
int64_t **val, uint_t *nelem);


int nvlist_lookup_uint64_array(nvlist_t *nvl, const char *name,
uint64_t **val, uint_t *nelem);


int nvlist_lookup_string_array(nvlist_t *nvl, const char *name,
char ***val, uint_t *nelem);


int nvlist_lookup_nvlist_array(nvlist_t *nvl, const char *name,
nvlist_t ***val, uint_t *nelem);


int nvlist_lookup_pairs(nvlist_t *nvl, int flag...);


PARAMETERS


nvl
The nvlist_t to be processed.


name
Name of the name-value pair to search.


nelem
Address to store the number of elements in value.


val
Address to store the starting address of the value.


flag
Specify bit fields defining lookup behavior:

NV_FLAG_NOENTOK
The retrieval function will not fail if
no matching name-value pair is found.


DESCRIPTION


These functions find the nvpair (name-value pair) that matches the
name and type as indicated by the interface name. If one is found,
nelem and val are modified to contain the number of elements in value
and the starting address of data, respectively.


These functions work for nvlists (lists of name-value pairs)
allocated with NV_UNIQUE_NAME or NV_UNIQUE_NAME_TYPE specified in
nvlist_alloc(3NVPAIR). If this is not the case, the function returns
ENOTSUP because the list potentially contains multiple nvpairs with
the same name and type.


Multiple threads can simultaneously read the same nvlist_t but only
one thread can actively change a given nvlist_t at a time. The caller
is responsible for the synchronization.


All memory required for storing the array elements, including string
value, are managed by the library. References to such data remain
valid until nvlist_free() is called on nvl.


The nvlist_lookup_pairs() function retrieves a set of nvpairs. The
arguments are a null-terminated list of pairs (data type
DATA_TYPE_BOOLEAN), triples (non-array data types) or quads (array
data types). The interpretation of the arguments depends on the value
of type (see nvpair_type(3NVPAIR)) as follows:

name
Name of the name-value pair to search.


type
Data type (see nvpair_type(3NVPAIR)).


val
Address to store the starting address of the value. When
using data type DATA_TYPE_BOOLEAN, the val argument is
omitted.


nelem
Address to store the number of elements in value. Non-array
data types have only one argument and nelem is omitted.


The order of the arguments is name, type, [val], [nelem].


When using NV_FLAG_NOENTOK and no matching name-value pair is found,
the memory pointed to by val and nelem is left untouched.

RETURN VALUES


These functions return 0 on success and an error value on failure.

ERRORS


These functions will fail if:

EINVAL
There is an invalid argument.


ENOENT
No matching name-value pair is found.


ENOTSUP
An encode/decode method is not supported.


ATTRIBUTES


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


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Committed |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO


libnvpair(3LIB), nvlist_alloc(3NVPAIR), nvpair_type(3NVPAIR),
attributes(7)

September 12, 2020
NVLIST_LOOKUP_BOOLEAN(3NVPAIR)

tribblix@gmail.com :: GitHub :: Privacy