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[unleashed/tickless.git] / usr / src / lib / libnwam / README

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NAME
        libnwam - Network Auto-Magic (NWAM) configuration and event
        management library

DESCRIPTION

The libnwam library is provided so that the various consumers of
Network Auto-Magic (NWAM) configuration information - i.e. the NWAM
GUI, the nwamcfg CLI and the NWAM daemon - have a consistent interface
for retrieving and updating NWAM-related configuration data, abstracted
from the actual manner in which the data is persistently stored. It
provides functionality to interact with the key components of NWAM
configuration, as described below.  Additionally the library provides
functionality for system events to flow from the NWAM daemon to a
client (like the GUI panel applet).

Each of these configuration components is referred to as an 'entity'.

Network Configuration Units (NCUs): units that specify either link or
interface (IP) configuration. An NCP consists of a set of NCUs, one for
each datalink (physical, tunnel, aggregation etc), and one for each IP
interface.

Network Configuration Profiles (NCPs): A network configuration profile (NCP)
comprises of a set of NCUs specifying configuration preferences to be applied
when that profile is active.

Locations: A location consists of additional configuration preferences
to be applied when basic IP configuration is complete.  Information
such as name service specification, proxies, etc. can be specified.

External Network Modifiers (ENMs): units that specify an external service
or executable that modifies the network configuration.  Properties of an
ENM include an FMRI or Start and Stop exec strings, an optional environment
which will be activated when the ENM is started, an activation type specifying
when the ENM should be started (e.g. on user input, dependent on an NCU--
either requiring or excluding a particular NCU, or always-on).  Each ENM
also has a read-only state property, which indicates whether or not the
ENM has been activated by nwam.

Known WiFi Networks (known WLANs): units that specify configuration
data associated with known WiFi access points that the user visits.  If
a WLAN found by scanning is one of the known WLANs, NWAM will automatically
connect.  Priorities associated with known WLANs can also be manipulated
allowing users to prioritize particular WLANs.

Events

The event interface allows a client of NWAM (usu. the GUI) to subscribe
to a stream of system events such as link and interface up/down,
wireless scans, and times when NWAM needs the user to be queried.

Events types are in libnwam.h as NWAM_EVENTS_* and the actual bodies of
the events are in nwam_events_msg_t.  The semantics of the events have
been simplified so that none require response.  They are all
notification.

NWAM_EVENTS_SOURCE_{DEAD,BACK} provide notification that the nwam
daemon has died or has reappeared.  These are synthetic events in that
they come from the library and not from nwamd.

NWAM_EVENTS_NO_MAGIC provides notification that nwam couldn't make a
determination of what to do without user guidance.  This event provides
information that can be used to ask the user if he wants to pick a
wireless lan although in some cases nwam might have no idea what is
intended.

NWAM_EVENTS_IF_{STATE,REMOVED} provide information about changes in
interface state or the removal of an interface.

NWAM_EVENTS_LINK_{STATE, REMOVED} provides information about changes in
link state or the removal of a link.

NWAM_EVENTS_SCAN_REPORT is used to communicate information about
wireless networks encountered.

Persistent configuration state of entities is stored in project-private
/etc/nwam configuration files, and the details of storage are hidden
from libnwam consumers.

Access to entities is attained via an entity-specific handle. These
handles can be obtained via calls to nwam_<entity>_create() or
nwam_<entity>_read(), and freed (in memory) via calls to nwam_<entity>_free().
nwam_<entity>_create() will create an in-memory representation of the
entity, but that entity will not be stored until nwam_<entity>_commit() is
called.  Persistently stored entitites are retrieved via nwam_<entity>_read(),
can be modified in-memory, and later persistently committed to storage
via nwam_<entity>_commit().  Entities can also be copied with
nwam_<entity>_copy().

All changes made after binding a handle to an entity, and prior to calling 
nwam_<entity>_commit() are carried out on the in-memory representation of that
entity. nwam_<entity>_commit() updates persistent storage in an all-or-none
transactional manner, applying the (possibly changed) in-memory representation
to persistent storage atomically.

To destroy an entity in persistent storage, nwam_<entity>_destroy() is
used. This is distinct from nwam_<entity>_free(), which simply frees 
the in-memory representation - destroy both removes the object from
persistent storage, and frees it in memory.

To summarize, the pattern of interactions with an entity is
 - nwam_<entity>_read(), nwam_<entity>_create() or nwam_<entity>_copy()
 - possibly modify entity properties
 - nwam_<entity>_commit() or nwam_<entity>_destroy()
 - nwam_<entity>_handle_free()

Unless otherwise stated functions in libnwam are MT-safe.  The
atomicity of _commit() and _read() operations is guaranteed - i.e.
_commit() is guaranteed to deliver all property changes to persistent
storage, while _read() is guaranteed to read a consistent view of the
entity (i.e. _read() cannot collide with another entity _commit()ting
changes). However, it is possible that a _read() will retrieve an
outdated view of an entity, if after the _read() completes, another
entity _commit()s changes. In other words, lost updates are possible.
These are permitted given the nature of the entities changing NWAM
configuration (the CLI and GUI) - it seems intuitive that the most
recent update best captures user intent.

Entity validation on an in-memory representation can be explicitly requested
via a call to nwam_<entity>_validate(), and individual property values
can be validated via nwam_<entity>_validate_prop().

Storage and retrieval of properties is done via nwam_<entity>_set_prop_value()
and nwam_<entity>_get_prop_value().  These functions require an nwam_value_t as
a parameter,  which is created via the nwam_value_create_<type>() family
of functions.  Data can be retrieved from the nwam_value_t via the
nwam_value_get_<type>() family of functions.  Once a property has been
set, the associated nwam_value_t can be immediately freed.  For retrieval,
the nwam_value_t should be freed when the value(s) are no longer needed.
A property can also be delete with nwam_<entity>_delete_prop().

Implicit validation occurs as part of the nwam_<entity>_set_prop_value()
and nwam_<entity>_commit() functions.

INTERFACES

For error handling:

const char *nwam_strerror(nwam_error_t error);

For values:

Values can be any of the following types:

        NWAM_VALUE_TYPE_BOOLEAN
        NWAM_VALUE_TYPE_UINT64
        NWAM_VALUE_TYPE_INT64
        NWAM_VALUE_TYPE_STRING

and are possibly multi-valued. An nwam_value_t must be created in order
to set property values in libnwam, this is done via the follwing functions:

nwam_error_t nwam_value_create_boolean(boolean_t, nwam_value_t *);
nwam_error_t nwam_value_create_boolean_array(boolean_t *, uint_t,
    nwam_value_t *);
nwam_error_t nwam_value_create_uint64(uint64_t, nwam_value_t *);
nwam_error_t nwam_value_create_uint64_array(uint64_t *, uint_t, nwam_value_t *);
nwam_error_t nwam_value_create_int64(int64_t, nwam_value_t *);
nwam_error_t nwam_value_create_int64_array(int64_t *, uint_t, nwam_value_t *);
nwam_error_t nwam_value_create_string(char *, nwam_value_t *);
nwam_error_t nwam_value_create_string_array(char **, uint_t, nwam_value_t *);

Values are returned from the _get_prop_value() functions, and the data
contained in them can be retrieved via the following functions:

nwam_error_t nwam_value_get_boolean(nwam_value_t, boolean_t *);
nwam_error_t nwam_value_get_boolean_array(nwam_value_t, boolean_t **, uint_t *);
nwam_error_t nwam_value_get_uint64(nwam_value_t, uint64_t *);
nwam_error_t nwam_value_get_uint64_array(nwam_value_t, uint64_t **, uint_t *);
nwam_error_t nwam_value_get_int64(nwam_value_t, int64_t *);
nwam_error_t nwam_value_get_int64_array(nwam_value_t, int64_t **, uint_t *);
nwam_error_t nwam_value_get_string(nwam_value_t, char **);
nwam_error_t nwam_value_get_string_array(nwam_value_t, char ***, uint_t *);

Type and number of value can be retrieved via:

nwam_error_t nwam_value_get_type(nwam_value_t, nwam_value_type_t *);
nwam_error_t nwam_value_get_numvalues(nwam_value_t, uint_t *);

and a value is freed using:

void nwam_value_free(nwam_value_t);

For property setting,  a typical set of events is to create the value,
call the appropriate set_prop_value() function, then free the value (values
can be safely freed prior to commit).  For retrieval, the type and
number of values usually need to be tested before calling the appropriate
retrieval function.  In this case, the value should not be freed until
the associated data is no longer needed.

NCUs,  locations and ENMs can all specify conditional activation conditions.
Interfaces are provided to convert a conditional activation predicate into
a string,  or from a string to a parsed set of variables that comprise the
condition.  Additionally a function is provided to rate the specificity of
the activation condition, used to compare location conditions to choose
the most specific condition to activate in the case where the activation
conditions of multiple locations are specified.

nwam_error_t nwam_condition_to_condition_string(nwam_condition_object_type_t,
    nwam_condition_t, const char *, char **);
nwam_error_t nwam_condition_string_to_condition(const char *,
    nwam_condition_object_type_t *, nwam_condition_t *, char **);
nwam_error_t nwam_condition_rate(nwam_condition_object_type_t,
    nwam_condition_t, uint64_t *);

For NCP entities:

nwam_error_t nwam_ncp_create(const char *name, uint64_t flags,
    nwam_ncp_handle_t *ncp);
nwam_error_t nwam_ncp_read(const char *name, uint64_t flags,
    nwam_ncp_handle_t *ncp);
nwam_error_t nwam_ncp_copy(nwam_ncp_handle_t ncp, const char *newname,
    nwam_ncp_handle_t *newncp);
nwam_error_t nwam_ncp_walk_ncus(nwam_ncp_handle_t ncp,
    int(*cb)(nwam_ncu_handle_t, void *), void *data, uint64_t flags, int *ret);
nwam_error_t nwam_ncp_get_name(nwam_ncp_handle_t ncp, char **name);
nwam_error_t nwam_ncp_activate(nwam_ncp_handle_t ncp);
nwam_error_t nwam_ncp_deactivate(nwam_ncp_handle_t ncp);
nwam_error_t nwam_ncp_destroy(nwam_ncp_handle_t ncp, uint64_t flags);
void nwam_ncp_free(nwam_ncp_handle_t ncp);

Since the NCP simply consists of the NCUs that comprise it, there is
no NCP-specific commit() function - we simply read the NCP, walk the
constituent NCUs, reading, changing or committing them in turn.  The
walk can be modified via the flags option to only select specific NCU types
and classes.

Each NCP has a set of NCUs associated with it, each of which is created/modifed
using the functions below.

For NCU entities:

nwam_error_t nwam_ncu_create(nwam_ncp_handle_t ncp, const char *name,
    nwam_ncu_type_t type, nwam_ncu_class_t class, nwam_ncu_handle_t *ncu);
nwam_error_t nwam_ncu_read(nwam_ncp_handle_t ncp, const char *name,
    nwam_ncu_type_t type, uint64_t flags, nwam_ncu_handle_t *ncu);
nwam_error_t nwam_ncu_copy(nwam_ncu_handle_t ncu, const char *newname,
    nwam_ncu_handle_t *newncu);
nwam_error_t nwam_ncu_commit(nwam_ncu_handle_t ncu, uint64_t flags);
nwam_error_t nwam_ncu_destroy(nwam_ncu_handle_t ncu, uint64_t flags);
nwam_error_t nwam_ncu_free(nwam_ncu_handle_t ncu);
nwam_error_t nwam_ncu_validate(nwam_ncu_handle_t ncu, const char **errprop);
nwam_error_t nwam_ncu_get_prop_value(nwam_ncu_handle_t ncu, const char *prop,
    nwam_value_t *value);
nwam_error_t nwam_ncu_get_prop_description(const char *prop,
    const char **description);
nwam_error_t nwam_ncu_delete_prop(nwam_ncu_handle_t ncu, const char *prop);
nwam_error_t nwam_ncu_set_prop_value(nwam_ncu_handle_t ncu, const char *prop,
    nwam_value_t value);
nwam_error_t nwam_ncu_get_name(nwam_ncu_handle_t ncu, char **name);
nwam_error_t nwam_ncu_set_name(nwam_ncu_handle_t ncu, const char *name);
nwam_error_t nwam_ncu_get_read_only(nwam_ncu_handle_t ncu, boolean_t *readp);
nwam_error_t nwam_ncu_validate_prop(nwam_ncu_handle_t ncu, const char *prop,
    nwam_value_t value);
nwam_error_t nwam_ncu_walk_props(nwam_ncu_handle_t ncu,
    int (*func)(void *, const char *, nwam_value_t), void *data,
    uint64_t flags, int *ret);
nwam_error_t nwam_ncu_prop_get_type(const char *prop,
    nwam_value_type_t *value_type);
nwam_error_t nwam_ncu_get_ncp(nwam_ncu_handle_t ncu, nwam_ncp_handle_t *ncp);

NCUs are manipulated via an nwam_ncu_handle_t.
 
Each NCU has a set of properties associated with it. Each property can
have mutiple values associated with it, which are set or retrieved via an
nwam_value_t.  The approach is similar to that used for Locations,   with
the difference that read/commit/destroy must specify an NCP.  Only two
NCPs are supported at present, the automatic and user NCPs. Modification
of the former is restricted to nwamd itself,  and attempts to modify
the automatic NCP's consituent NCUs will result in an NWAM_ENTITY_READ_ONLY
error.

For Location entities:

nwam_error_t nwam_loc_create(const char *name, nwam_loc_handle_t *loc);
nwam_error_t nwam_loc_read(const char *name, uint64_t flags,
    nwam_loc_handle_t *loc);
nwam_error_t nwam_loc_copy(nwam_loc_handle_t loc, const char *newname,
    nwam_loc_handle_t *newloc);
nwam_error_t nwam_walk_locs(int (*cb)(nwam_loc_handle_t loc, void *arg),
    void *arg, uint64_t flags, int *cbretp);
nwam_error_t nwam_loc_commit(nwam_loc_handle_t loc, uint64_t flags);
nwam_error_t nwam_loc_destroy(nwam_loc_handle_t loc, uint64_t flags);
void nwam_loc_free(nwam_loc_handle_t loc);
nwam_error_t nwam_loc_validate(nwam_loc_handle_t loc, const char *errprop);
nwam_error_t nwam_loc_walk_props(nwam_loc_handle_t loc,
    int (*cb)(const char *, nwam_value_t **, void *),
    void *arg, uint64_t flags, int *cbret);
nwam_error_t nwam_loc_validate_prop(nwam_loc_handle_t loc,
    const char *prop, nwam_value_t value);
nwam_error_t nwam_loc_prop_get_type(const char *prop,
    nwam_value_type_t *value_type);
nwam_error_t nwam_loc_get_prop_value(nwam_loc_handle_t loc, const char *prop,
    nwam_value_t *value);
nwam_error_t nwam_loc_get_prop_description(const char *prop,
    const char **description);
nwam_error_t nwam_loc_delete_prop(nwam_loc_handle_t loc, const char *prop);
nwam_error_t nwam_loc_set_prop_value(nwam_loc_handle_t loc, const char *prop,
    nwam_value_t value);
nwam_error_t nwam_loc_get_name(nwam_loc_handle_t loc, char **name);
nwam_error_t nwam_loc_set_name(nwam_loc_handle_t loc, const char *name);
nwam_error_t nwam_loc_activate(nwam_loc_handle_t loc);
nwam_error_t nwam_loc_deactivate(nwam_loc_handle_t loc);

Locations are manipulated via an nwam_loc_handle_t.

A loc handle maps to an in-memory representation of a location; operations via
this interface manipulate the in-memory data.  In-memory data is read from
persistant storage via the nwam_loc_read() or nwam_walk_locs() functions, and
written out to persistent storage via the nwam_loc_commit() function.  A loc
may be permanently removed from persistent storage with the nwam_loc_destroy()
function.  Interactions with persistent storage will be nonblocking by default;
this behavior can be changed by passing the NWAM_FLAG_BLOCKING in the flags
parameter.

A typical sequence would be to allocate a loc handle, either by creating a
new loc (nwam_loc_create()) or by reading one from persistent storage (nwam_
loc_read() or nwam_walk_locs()).  The various set/get/walk/validate/(de)activate
functions may then be used to manipulate the loc; any changes made may then be
committed to persistent storage via nwam_loc_commit().  A call to nwam_loc_
free() is required to release in-memory resources associated with the handle.

The flags parameter in the walk functions allows filtering of the locs that
will be examined, depending on the state of each loc.  Passing in
NWAM_FLAG_STATE_ALL will examine all locs; specific state flags are defined
in <libnwam.h>.

Like NCUs, each loc has a set of properties associated with it. Loc properties
are stored in nwam_value_t structures; see the Values section for how to store/
retrieve using these.

For ENM entities:

nwam_error_t nwam_enm_create(const char *name, const char *fmri,
    nwam_enm_handle_t *enm);
nwam_error_t nwam_enm_read(const char *name, uint64_t flags,
    nwam_enm_handle_t *enm);
nwam_error_t nwam_enm_copy(nwam_enm_handle_t enm, const char *newname,
    nwam_enm_handle_t *newenm);
nwam_error_t nwam_walk_enms(int (*cb)(nwam_enm_handle_t enm, void *arg),
    void *arg, uint64_t flags, int *cbretp);
nwam_error_t nwam_enm_commit(nwam_enm_handle_t enm, uint64_t flags);
nwam_error_t nwam_enm_destroy(nwam_enm_handle_t enm, uint64_t flags);
void nwam_enm_free(nwam_enm_handle_t enm);
nwam_error_t nwam_enm_validate(nwam_enm_handle_t enm, const char *errprop);
nwam_error_t nwam_enm_walk_props(nwam_enm_handle_t enm,
    int (*cb)(const char *, nwam_value_t **, void *),
    void *arg, uint64_t flags, int *cbret);
nwam_error_t nwam_enm_validate_prop(nwam_enm_handle_t enm,
    const char *prop, nwam_value_t value);
nwam_error_t nwam_enm_prop_get_type(const char *prop,
    nwam_value_type_t *value_type);
nwam_error_t nwam_enm_get_prop_value(nwam_enm_handle_t enm, const char *prop,
    nwam_value_t *value);
nwam_error_t nwam_enm_get_prop_description(const char *prop,
    const char **description);
nwam_error_t nwam_enm_delete_prop(nwam_enm_handle_t enm, const char *prop);
nwam_error_t nwam_enm_set_prop_value(nwam_enm_handle_t enm, const char *prop,
    nwam_value_t value);
nwam_error_t nwam_enm_get_name(nwam_enm_handle_t enm, char **name);
nwam_error_t nwam_enm_set_name(nwam_enm_handle_t enm, const char *name);
nwam_error_t nwam_enm_activate(nwam_enm_handle_t enm);
nwam_error_t nwam_enm_deactivate(nwam_enm_handle_t enm);

ENMs are manipulated via an nwam_enm_handle_t, in a similar manner to
NCUs and locations.

The flags parameter in the walk functions allows filtering of the ENMs that
will be examined, depending on the state of each ENM.  Passing in
NWAM_FLAG_STATE_ALL will examine all ENMs; specific state flags are defined
in <libnwam.h>.

Like NCUs, each ENM has a set of properties associated with it. ENM properties
are all single valued, though the interface is aligned with the NCU interface,
which allows for multi-valued properties.  ENM properties are stored in
nwam_value_t structures; see the Values section for how to store/retrieve
using these.

For known WLAN entities:

nwam_error_t nwam_known_wlan_create(const char *name,
    nwam_known_wlan_handle_t *kwhp);
nwam_error_t nwam_known_wlan_read(const char *name, uint64_t flags,
    nwam_known_wlan_handle_t *kwhp);
nwam_error_t nwam_known_wlan_copy(nwam_known_wlan_handle_t kwh,
    const char *newname, nwam_known_wlan_handle_t *newkwh);
nwam_error_t nwam_walk_known_wlans(int (*cb)(nwam_known_wlan_handle_t, void *),
    void *arg, uint64_t flags, int *cbretp);
nwam_error_t nwam_known_wlan_commit(nwam_known_wlan_handle_t kwh,
    uint64_t flags);
nwam_error_t nwam_known_wlan_destroy(nwam_known_wlan_handle_t kwh,
    uint64_t flags);
void nwam_known_wlan_free(nwam_known_wlan_handle_t kwh);
nwam_error_t nwam_known_wlan_validate(nwam_known_wlan_handle_t kwh,
    const char *errprop);
nwam_error_t nwam_known_wlan_walk_props(nwam_known_wlan_handle_t kwh, 
    int (*cb)(const char *, nwam_value_t **, void *),
    void *arg, uint64_t flags, int *cbret);
nwam_error_t nwam_known_wlan_validate_prop(nwam_known_wlan_handle_t kwh,
    const char *prop, nwam_value_t value);
nwam_error_t nwam_known_wlan_prop_get_type(const char *prop,
    nwam_value_type_t *value_type);
nwam_error_t nwam_known_wlan_get_prop_value(nwam_known_wlan_handle_t kwh,
    const char *prop, nwam_value_t *value);
nwam_error_t nwam_known_wlan_get_prop_description(const char *prop,
    const char **description);
nwam_error_t nwam_known_wlan_delete_prop(nwam_known_wlan_handle_t kwh,
    const char *prop);
nwam_error_t nwam_known_wlan_set_prop_value(nwam_known_wlan_handle_t kwh,
    const char *prop, nwam_value_t value);
nwam_error_t nwam_known_wlan_get_name(nwam_known_wlan_handle_t kwh,
    char **name);
nwam_error_t nwam_known_wlan_set_name(nwam_known_wlan_handle_t kwh,
    const char *name);
nwam_error_t nwam_known_wlan_add_to_known_wlan(const char *essid,
    const char *bssid);
nwam_error_t nwam_known_wlan_remove_from_known_wlan(const char *essid,
    const char *bssid);

Known WLANs are manipulated via an nwam_known_wlan_handle_t, in a similar
manner to NCUs, locations and ENMs.

Like ENMs, each known WLAN has a set of properties associated with it.
Known WLAN properties are stored in nwam_value_t structures; see the Values
section for how to store/retrieve using these.

For WLANs, we define a set of functions to ask nwamd to initiate a scan,
select a WLAN (and possibly add it to the known WLAN list) or set a WLAN
key:


extern nwam_error_t nwam_wlan_scan(const char *linkname);
extern nwam_error_t nwam_wlan_get_scan_results(const char *linkname,
    uint_t *num_resultsp, nwam_wlan_t **wlansp);
extern nwam_error_t nwam_wlan_select(const char *linkname,
    const char *essid, const char *bssid, boolean_t add_to_known_wlans);
extern nwam_error_t nwam_wlan_set_key(const char *linkname, const char *essid,
    const char *bssid, uint32_t security_mode, uint_t keyslot, const char *key);

For Events:

typedef struct nwam_event {
        uint32_t type;

        union {
                struct {
                        nwam_object_type_t object_type;
                        char name[NWAM_MAX_NAME_LEN];
                        nwam_action_t action;
                } object_action;


                ... and so on for each message ...

        } data;

} *nwam_event_t;

type comes from the set of constants NWAM_EVENT_TYPE_*.

Registration and cancellation of registration are done via
_init and _fini functions:

extern nwam_error_t nwam_events_init(void);
extern void nwam_events_fini(void);

Events can then be recieved by calling nwam_event_wait():

extern nwam_error_t nwam_event_wait(nwam_event_t *);

The event can then be processed, and free via nwam_event_free();

RETURN VALUES

All functions return an nwam_error_t if they return an error. Possible
errors are:

        NWAM_SUCCESS                    No error occured
        NWAM_LIST_END                   End of list
        NWAM_INVALID_HANDLE             Entity handle is invalid
        NWAM_HANDLE_UNBOUND             Handle not bound to entity
        NWAM_INVALID_ARG                Argument is invalid
        NWAM_PERMISSION_DENIED          Insufficient privileges for action
        NWAM_NO_MEMORY                  Out of memory
        NWAM_ENTITY_EXISTS              Entity already exists
        NWAM_ENTITY_IN_USE              Another user is interacting with entity
        NWAM_ENTITY_COMMITTED           Entity already committed
        NWAM_ENTITY_NOT_FOUND           Entity not found
        NWAM_ENTITY_TYPE_MISMATCH       Entity value-type mismatch
        NWAM_ENTITY_INVALID             Validation of entity failed
        NWAM_ENTITY_INVALID_MEMBER      Entity member invalid
        NWAM_ENTITY_INVALID_VALUE       Validation of entity value failed
        NWAM_ENTITY_NO_VALUE            No value associated with entity   
        NWAM_ENTITY_MULTIPLE_VALUES,    Multiple values for entity
        NWAM_ENTITY_READ_ONLY,          Entity is marked read only
        NWAM_WALK_HALTED,               Callback function returned nonzero
        NWAM_ERROR_BIND,                Could not bind to backend
        NWAM_ERROR_BACKEND_INIT,        Could not initialize backend
        NWAM_ERROR_INTERNAL             Internal error

FILES
        /lib/libnwam.so.1       shared object

ATTRIBUTES


SEE ALSO
        nwamd(1M), nwamcfg(1M), nwamadm(1M)