> For the complete documentation index, see [llms.txt](https://sandbox-docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sandbox-docs.verifone.com/adk-5.0-programmers-guide/readme/files/dir_1e776ad494434554ed2e1a73460819d8/dir_dc5dfd6157a1d65d3f69cd65a617f88c/libevt_8h.md).

# libevt.h

[Data Structures](#nested-classes) | [Macros](#define-members) | [Typedefs](#typedef-members) | [Enumerations](#enum-members) | [Functions](#func-members) | [Variables](#var-members)

`#include <stdint.h>`

Include dependency graph for libevt.h:

![](/files/azzgzGu3VtSBW1gXTCCL)

[Go to the source code of this file.](/adk-5.0-programmers-guide/libevt_8h_source.md)

|                 |                        |
| --------------- | ---------------------- |
| Data Structures |                        |
| struct          | [Event](#struct_event) |

|         |                                                |
| ------- | ---------------------------------------------- |
| Macros  |                                                |
| #define | [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) |

|                           |                                                                                                                     |
| ------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| Typedefs                  |                                                                                                                     |
| typedef unsigned long int | [WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6)                                                                  |
|                           | <p>Waiting handle type. <a href="#a7ba4b46d2481427f399dda29a67aaab6">More...</a><br></p>                            |
| typedef uint64\_t         | [UID](#a83aa1253e238763a389f784ff78d569e)                                                                           |
|                           | <p>Unique ID of <a href="#struct_event">Event</a>. <a href="#a83aa1253e238763a389f784ff78d569e">More...</a><br></p> |

|              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Enumerations |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| enum         | <p><a href="#a47782499daa82ca02ceec0dde367c162">OSEvents</a> {<br>  <a href="#a47782499daa82ca02ceec0dde367c162a46e70b83f1a2498c9325b00cb2cf4e3e">OS\_NOP</a> = 0, <a href="#a47782499daa82ca02ceec0dde367c162a55c5d33fac553b62a4a2988c2b53af96">OS\_EVT\_TIMER</a>, <a href="#a47782499daa82ca02ceec0dde367c162aec9658ee40107e166a1dac5d8efc29a1">OS\_EVT\_DOCK</a>, <a href="#a47782499daa82ca02ceec0dde367c162a37f3b245fe203131c78859388aa7d6ec">OS\_EVT\_UNDOCK</a>,<br>  <a href="#a47782499daa82ca02ceec0dde367c162ae25c516903050b08d5cd015e625bf3af">OS\_EVT\_SHUTDOWN</a><br>}</p> |
| enum         | [WaitPolicy](#a7d8e96aac2c9ffc0945f804832b93305) { [WAIT\_ANY](#a7d8e96aac2c9ffc0945f804832b93305a2a6b8a36eb30e1a3e433912876977446), [WAIT\_ALL](#a7d8e96aac2c9ffc0945f804832b93305a5ee1ddeefe68a1f2a66eb8fa6440f0ba) }                                                                                                                                                                                                                                                                                                                                                                    |
| enum         | [EvtSide](#a45a13daa32f946f8dd819ee734fbf236) { [SIDE\_RAISER](#a45a13daa32f946f8dd819ee734fbf236ad699859f8546fbfb9ca1eab82e1a3586) = 0, [SIDE\_WAITER](#a45a13daa32f946f8dd819ee734fbf236af860bd783aa79d81ad43ab8c164da7a8), [SIDE\_BOTH](#a45a13daa32f946f8dd819ee734fbf236a367c08987c7a0052de86e72ffc318d97) }                                                                                                                                                                                                                                                                          |
| enum         | [EvtOptions](#aaeb183a7a4790d18f96fa3755b1cbc42) { [EVT\_OPT\_DEFAULT](#aaeb183a7a4790d18f96fa3755b1cbc42aef88812f61bd57953fff8fa42b9a6fd0) = 0, [EVT\_OPT\_COPY\_NEW\_ONLY\_EVENTS\_IN\_GET\_BY\_HANDLE\_FUNC](#aaeb183a7a4790d18f96fa3755b1cbc42a3256b804f3c9350097da691390b88f76) = 0x1 << 0 }                                                                                                                                                                                                                                                                                          |

|                                                                                                   |                                                                                                                                                                                               |
| ------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Functions                                                                                         |                                                                                                                                                                                               |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) [UID](#a83aa1253e238763a389f784ff78d569e)          | [evt\_make\_uid](#a886f0a69446395a4013dc45380f4128f) (uint16\_t componentID, uint16\_t eventID)                                                                                               |
|                                                                                                   | <p>Creates UID based on componentID and eventID. <a href="#a886f0a69446395a4013dc45380f4128f">More...</a><br></p>                                                                             |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) [UID](#a83aa1253e238763a389f784ff78d569e)          | [evt\_make\_uid\_os](#afb47263c3337482a275b6cecf497204b) (uint16\_t componentID, [OSEvents](#a47782499daa82ca02ceec0dde367c162) osEvent)                                                      |
|                                                                                                   | <p>Creates UID based on componentID and OS <a href="#struct_event">Event</a>. <a href="#afb47263c3337482a275b6cecf497204b">More...</a><br></p>                                                |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) uint16\_t                                          | [evt\_get\_component\_id](#a2063afa16979be3952b393dd81bfd5f8) ([UID](#a83aa1253e238763a389f784ff78d569e))                                                                                     |
|                                                                                                   | <p>Returns componentID part of UID. <a href="#a2063afa16979be3952b393dd81bfd5f8">More...</a><br></p>                                                                                          |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) long                                               | [evt\_start\_timer](#af7e23c1a0a2e9a3caa6faf55c3aae1d4) (uint32\_t timeout)                                                                                                                   |
|                                                                                                   | <p>Starts a new timer. <a href="#af7e23c1a0a2e9a3caa6faf55c3aae1d4">More...</a><br></p>                                                                                                       |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) void                                               | [evt\_stop\_timer](#a6f6a659420a37bb9e1d1b07edfe419a2) (long handle)                                                                                                                          |
|                                                                                                   | <p>Deletes a timer. <a href="#a6f6a659420a37bb9e1d1b07edfe419a2">More...</a><br></p>                                                                                                          |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_init](#a799ffc9044180e2968690455cfb5d8cf) ([EvtSide](#a45a13daa32f946f8dd819ee734fbf236) side, uint16\_t componentID, uint8\_t capacity)                                                |
|                                                                                                   | <p>Initialize EVT library. <a href="#a799ffc9044180e2968690455cfb5d8cf">More...</a><br></p>                                                                                                   |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_destroy](#af8fba20f70dc5d4274484f3d3eaf0fc2) ()                                                                                                                                         |
|                                                                                                   | <p>De-initialize EVT library. <a href="#af8fba20f70dc5d4274484f3d3eaf0fc2">More...</a><br></p>                                                                                                |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_wait](#adb08919483f2094f1927d67dad595278) ([Event](#struct_event) \*event, int timeout)                                                                                                 |
|                                                                                                   | <p>Wait for a single event. <a href="#adb08919483f2094f1927d67dad595278">More...</a><br></p>                                                                                                  |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_wait\_group](#ab26c08b8228d47a7b83144e5ec6d9c4e) ([Event](#struct_event) \*events, uint32\_t count, int timeout, [WaitPolicy](#a7d8e96aac2c9ffc0945f804832b93305) policy)               |
|                                                                                                   | <p>Wait for a group of events. <a href="#ab26c08b8228d47a7b83144e5ec6d9c4e">More...</a><br></p>                                                                                               |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_raise](#a2855073610dc2b9210a25468926cfecc) ([Event](#struct_event) \*event)                                                                                                             |
|                                                                                                   | <p>Raise an event. <a href="#a2855073610dc2b9210a25468926cfecc">More...</a><br></p>                                                                                                           |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) [WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) | [evt\_init\_waiter](#a76bffba58228fdcd95671e17bf8ad041) ([Event](#struct_event) \*events, uint32\_t count)                                                                                    |
|                                                                                                   | <p>Initialize asynchronous waiter for a group of events. <a href="#a76bffba58228fdcd95671e17bf8ad041">More...</a><br></p>                                                                     |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_get\_by\_handle](#a9fbabdeb66cb9541e4a4c146b7e1658a) ([WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) waiter, [Event](#struct_event) \*events, uint32\_t count)                      |
|                                                                                                   | <p>Get events so far collected by asynchronous waiter. <a href="#a9fbabdeb66cb9541e4a4c146b7e1658a">More...</a><br></p>                                                                       |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_peek\_by\_handle](#a793d32176ee75ec31b31f1fb1cd6abbc) ([WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) waiter, [Event](#struct_event) \*events, uint32\_t count)                     |
|                                                                                                   | <p>Peek events so far collected by asynchronous waiter. <a href="#a793d32176ee75ec31b31f1fb1cd6abbc">More...</a><br></p>                                                                      |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_wait\_by\_handle](#a57f2c3182b0ea176490a1735324de25e) ([WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) handle, int timeout, [WaitPolicy](#a7d8e96aac2c9ffc0945f804832b93305) policy) |
|                                                                                                   | <p>Blocks thread execution until waiter receive an event or timeout occurs. <a href="#a57f2c3182b0ea176490a1735324de25e">More...</a><br></p>                                                  |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_destroy\_waiter](#a09b61b8da3127a2c067df17d29be4f1f) ([WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) waiter)                                                                        |
|                                                                                                   | <p>Stops and destroys the asynchronous waiter. <a href="#a09b61b8da3127a2c067df17d29be4f1f">More...</a><br></p>                                                                               |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) void                                               | [evt\_set\_options](#a5e8063c63d656262cf58b6336b270502) (int options)                                                                                                                         |
|                                                                                                   | <p>Set options changing behavior of ADK-EVT engine. <a href="#a5e8063c63d656262cf58b6336b270502">More...</a><br></p>                                                                          |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [evt\_get\_options](#aee16ce74c4a65f2ac2952bfd2f06dd27) ()                                                                                                                                    |
|                                                                                                   | <p>Get options. <a href="#aee16ce74c4a65f2ac2952bfd2f06dd27">More...</a><br></p>                                                                                                              |
| const [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) char \*                                      | [evt\_getVersion](#a1a7daf80470e0ad3b570ec8fc680821d) ()                                                                                                                                      |
|                                                                                                   | <p>get version of a library <a href="#a1a7daf80470e0ad3b570ec8fc680821d">More...</a><br></p>                                                                                                  |
| [EVT\_API](#a7e6311173510f4660ef3c2d2f234f429) int                                                | [get\_dock\_sts](#adc9d1c34c7762b01b3b9830f1f70c6ed) ()                                                                                                                                       |
|                                                                                                   | <p>Returns unit dock status. <a href="#adc9d1c34c7762b01b3b9830f1f70c6ed">More...</a><br></p>                                                                                                 |

|                                                          |                                                                                                                                                          |
| -------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Variables                                                |                                                                                                                                                          |
| const long                                               | [EVT\_ANY\_HANDLE](#a63090fb17900201d2517be5e555b7d87) = -1                                                                                              |
|                                                          | <p>Timer <a href="#struct_event">Event</a> mask that allow to receive all timer events. <a href="#a63090fb17900201d2517be5e555b7d87">More...</a><br></p> |
| const [WaiterHandle](#a7ba4b46d2481427f399dda29a67aaab6) | [EVT\_INVALID\_HANDLE](#a468c3786a00e38b1d61d083fa0b4ce96) = 0                                                                                           |
|                                                          | <p>Invalid WaiterHandle value. <a href="#a468c3786a00e38b1d61d083fa0b4ce96">More...</a><br></p>                                                          |
| const int                                                | [EVT\_INFINITE\_WAIT](#a35fc755ca0569e2acb759e0d683a2fb5) = -1                                                                                           |
|                                                          | <p>Timeout value for infinite wait. <a href="#a35fc755ca0569e2acb759e0d683a2fb5">More...</a><br></p>                                                     |
| const uint32\_t                                          | [EVT\_DATA\_SIZE](#adb6493cdff512931871b2239b71215c2) = 64                                                                                               |
|                                                          | <p>Size of <a href="#struct_event">Event</a> additional data. <a href="#adb6493cdff512931871b2239b71215c2">More...</a><br></p>                           |
| const uint32\_t                                          | [EVT\_MAX\_COUNT](#ac34c5452c5be1c370c9c3bf70044d4e0) = 256                                                                                              |
|                                                          | <p>Maximal event count to wait for. <a href="#ac34c5452c5be1c370c9c3bf70044d4e0">More...</a><br></p>                                                     |

***

### DataStructure Documentation <a href="#data-structure-documentation" id="data-structure-documentation"></a>

### Event <a href="#struct_event" id="struct_event"></a>

struct Event

ADK [Event](#struct_event) structure.

|                                           |                                                                      |                                                                                |
| ----------------------------------------- | -------------------------------------------------------------------- | ------------------------------------------------------------------------------ |
| Data Fields                               |                                                                      |                                                                                |
| long                                      | handle                                                               | OS [Event](#struct_event) handle or EVT\_ANY\_HANDLE.                          |
| [UID](#a83aa1253e238763a389f784ff78d569e) | id                                                                   | [Event](#struct_event) ID. Must be specified by both raise and wait sides.     |
| char                                      | raised\_data\[[EVT\_DATA\_SIZE](#adb6493cdff512931871b2239b71215c2)] | Additional data for received [Event](#struct_event).                           |
| uint8\_t                                  | raised\_flag                                                         | Raising flag. Indicates that [Event](#struct_event) was successfully received. |
| long                                      | raised\_handle                                                       | OS [Event](#struct_event) return Handle.                                       |
| uint64\_t                                 | raised\_timestamp                                                    | Timestamp of raised event. Unix time in seconds.                               |
| uint16\_t                                 | raised\_version                                                      | [Event](#struct_event) version. Data is componentID/eventID specific.          |

### MacroDefinition Documentation <a href="#macro-definition-documentation" id="macro-definition-documentation"></a>

### EVT\_API <a href="#a7e6311173510f4660ef3c2d2f234f429" id="a7e6311173510f4660ef3c2d2f234f429"></a>

\#define EVT\_API

### TypedefDocumentation <a href="#typedef-documentation" id="typedef-documentation"></a>

### UID <a href="#a83aa1253e238763a389f784ff78d569e" id="a83aa1253e238763a389f784ff78d569e"></a>

typedef uint64\_t \[UID]\(#a83aa1253e238763a389f784ff78d569e)

Unique ID of [Event](#struct_event).

### WaiterHandle <a href="#a7ba4b46d2481427f399dda29a67aaab6" id="a7ba4b46d2481427f399dda29a67aaab6"></a>

typedef unsigned long int \[WaiterHandle]\(#a7ba4b46d2481427f399dda29a67aaab6)

Waiting handle type.

### EnumerationType Documentation <a href="#enumeration-type-documentation" id="enumeration-type-documentation"></a>

### EvtOptions <a href="#aaeb183a7a4790d18f96fa3755b1cbc42" id="aaeb183a7a4790d18f96fa3755b1cbc42"></a>

enum \[EvtOptions]\(#aaeb183a7a4790d18f96fa3755b1cbc42)

EVT engine options

|                                                              |   |
| ------------------------------------------------------------ | - |
| Enumerator                                                   |   |
| EVT\_OPT\_DEFAULT                                            |   |
| EVT\_OPT\_COPY\_NEW\_ONLY\_EVENTS\_IN\_GET\_BY\_HANDLE\_FUNC |   |

### EvtSide <a href="#a45a13daa32f946f8dd819ee734fbf236" id="a45a13daa32f946f8dd819ee734fbf236"></a>

enum \[EvtSide]\(#a45a13daa32f946f8dd819ee734fbf236)

|              |   |
| ------------ | - |
| Enumerator   |   |
| SIDE\_RAISER |   |
| SIDE\_WAITER |   |
| SIDE\_BOTH   |   |

### OSEvents <a href="#a47782499daa82ca02ceec0dde367c162" id="a47782499daa82ca02ceec0dde367c162"></a>

enum \[OSEvents]\(#a47782499daa82ca02ceec0dde367c162)

|                   |   |
| ----------------- | - |
| Enumerator        |   |
| OS\_NOP           |   |
| OS\_EVT\_TIMER    |   |
| OS\_EVT\_DOCK     |   |
| OS\_EVT\_UNDOCK   |   |
| OS\_EVT\_SHUTDOWN |   |

### WaitPolicy <a href="#a7d8e96aac2c9ffc0945f804832b93305" id="a7d8e96aac2c9ffc0945f804832b93305"></a>

enum \[WaitPolicy]\(#a7d8e96aac2c9ffc0945f804832b93305)

Waiting policies for event groups.

|            |                                                        |
| ---------- | ------------------------------------------------------ |
| Enumerator |                                                        |
| WAIT\_ANY  |                                                        |
| WAIT\_ALL  | Stop waiting if at least 1 event from group is raised. |

### FunctionDocumentation <a href="#function-documentation" id="function-documentation"></a>

### evt\_destroy() <a href="#af8fba20f70dc5d4274484f3d3eaf0fc2" id="af8fba20f70dc5d4274484f3d3eaf0fc2"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_destroy

De-initialize EVT library.

Destroys caching structures, do cleanup. Make sure all waiters are stopped before this call. Must be called from the same thread that called [evt\_init()](#a799ffc9044180e2968690455cfb5d8cf). [evt\_init()](#a799ffc9044180e2968690455cfb5d8cf)/evt\_destroy() lifecycle calls must be serialized by the caller; concurrent calls cause undefined behavior.

#### Returns

Negative: error with errno value. 0: Library successfully de-initialized.

### evt\_destroy\_waiter() <a href="#a09b61b8da3127a2c067df17d29be4f1f" id="a09b61b8da3127a2c067df17d29be4f1f"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_destroy\_waiter

Stops and destroys the asynchronous waiter.

Send waiter thread an exit signal then join the thread. Must not be called while [evt\_wait\_by\_handle()](#a57f2c3182b0ea176490a1735324de25e), [evt\_get\_by\_handle()](#a9fbabdeb66cb9541e4a4c146b7e1658a) or [evt\_peek\_by\_handle()](#a793d32176ee75ec31b31f1fb1cd6abbc) runs concurrently on the same handle: the caller must make sure such calls have returned first, otherwise behavior is undefined.

**Parameters**

**waiter** A handle created by evt\_init\_waiter(). Passing here already destroyed handle cause an undefined behavior.

#### Returns

Negative: error with errno value. 0: on success.

### evt\_get\_by\_handle() <a href="#a9fbabdeb66cb9541e4a4c146b7e1658a" id="a9fbabdeb66cb9541e4a4c146b7e1658a"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_get\_by\_handle

Get events so far collected by asynchronous waiter.

Function returns immediately. Returns either all or only 'new' events (collected from the last call), depends from EVT\_OPT\_COPY\_NEW\_ONLY\_EVENTS\_IN\_GET\_BY\_HANDLE\_FUNC compatibility option.

**Parameters**

**waiter** A handle created by evt\_init\_waiter(). Passing here a destroyed handle cause an undefined behavior. **events** Array of Events to fill. **count** Number of events represented in 'events' param. (Must be equal or more as passed to evt\_init\_waiter()).

#### Returns

Negative: error with errno value. 0: success but there is no raised event (since last call). Positive: returns number of raised events. Events are copied to 'events' member.

### evt\_get\_component\_id() <a href="#a2063afa16979be3952b393dd81bfd5f8" id="a2063afa16979be3952b393dd81bfd5f8"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) uint16\_t evt\_get\_component\_id

Returns componentID part of UID.

**Parameters**

**UID**

#### Returns

componentID

### evt\_get\_options() <a href="#aee16ce74c4a65f2ac2952bfd2f06dd27" id="aee16ce74c4a65f2ac2952bfd2f06dd27"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_get\_options

Get options.

#### Returns

the options set

### evt\_getVersion() <a href="#a1a7daf80470e0ad3b570ec8fc680821d" id="a1a7daf80470e0ad3b570ec8fc680821d"></a>

const \[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) char\\\* evt\_getVersion

get version of a library

#### Returns

string with version

### evt\_init() <a href="#a799ffc9044180e2968690455cfb5d8cf" id="a799ffc9044180e2968690455cfb5d8cf"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_init

Initialize EVT library.

Creates caching structures, sets ignore to SIGPIPE signal (V/OS - raiser side).

**Parameters**

**side** Side to be initialized. **componentID** System wide component ID. **capacity** Estimated number of unique events to be processed.

#### Returns

Negative: error with errno value. 0: Library successfully initialized.

### evt\_init\_waiter() <a href="#a76bffba58228fdcd95671e17bf8ad041" id="a76bffba58228fdcd95671e17bf8ad041"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) \[WaiterHandle]\(#a7ba4b46d2481427f399dda29a67aaab6) evt\_init\_waiter

Initialize asynchronous waiter for a group of events.

**Parameters**

**events** Array of Events to wait for. Caller is responsible to provide only unique ID. **count** Number of events represented in 'events' param.

#### Returns

EVT\_INVALID\_HANDLE on failure or valid WaiterHandle otherwise.

### evt\_make\_uid() <a href="#a886f0a69446395a4013dc45380f4128f" id="a886f0a69446395a4013dc45380f4128f"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) \[UID]\(#a83aa1253e238763a389f784ff78d569e) evt\_make\_uid

Creates UID based on componentID and eventID.

UID Creation helper function for user events.

**Parameters**

**componentID** System wide component ID. **eventID** Component wide event ID.

#### Returns

[Event](#struct_event) UID.

### evt\_make\_uid\_os() <a href="#afb47263c3337482a275b6cecf497204b" id="afb47263c3337482a275b6cecf497204b"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) \[UID]\(#a83aa1253e238763a389f784ff78d569e) evt\_make\_uid\_os

Creates UID based on componentID and OS [Event](#struct_event).

UID Creation helper function for OS events.

**Parameters**

**componentID** System wide component ID. **osEvent** OS Event.

#### Returns

[Event](#struct_event) UID.

### evt\_peek\_by\_handle() <a href="#a793d32176ee75ec31b31f1fb1cd6abbc" id="a793d32176ee75ec31b31f1fb1cd6abbc"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_peek\_by\_handle

Peek events so far collected by asynchronous waiter.

Function returns immediately. Returns either all or only 'new' events, depends from EVT\_OPT\_COPY\_NEW\_ONLY\_EVENTS\_IN\_GET\_BY\_HANDLE\_FUNC compatibility option.

**Parameters**

**waiter** A handle created by evt\_init\_waiter(). Passing here a destroyed handle cause an undefined behavior. **events** Array of Events to fill. **count** Number of events represented in 'events' param. (Must be equal or more as passed to evt\_init\_waiter()).

#### Returns

Negative: error with errno value. 0: success but there is no raised event (since last call). Positive: returns number of raised events. Events are copied to 'events' member.

### evt\_raise() <a href="#a2855073610dc2b9210a25468926cfecc" id="a2855073610dc2b9210a25468926cfecc"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_raise

Raise an event.

Raise an event specified by 'event'. Works synchronously and returns after event is sent.

**Parameters**

**event** An Event to raise.

#### Returns

Negative: error with errno value. 0: [Event](#struct_event) successfully raised.

### evt\_set\_options() <a href="#a5e8063c63d656262cf58b6336b270502" id="a5e8063c63d656262cf58b6336b270502"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) void evt\_set\_options

Set options changing behavior of ADK-EVT engine.

**Parameters**

**options** The options are coded as bitmasks and can be combined by a logical or operation. All available options are collected in EvtOptions enum.

### evt\_start\_timer() <a href="#af7e23c1a0a2e9a3caa6faf55c3aae1d4" id="af7e23c1a0a2e9a3caa6faf55c3aae1d4"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) long evt\_start\_timer

Starts a new timer.

Schedules an event after a timeout.

**Parameters**

**timeout** Timeout in ms. Max value is 24h (86,400,000 ms)

#### Returns

Negative: error with errno value. Non negative: timer handle.

### evt\_stop\_timer() <a href="#a6f6a659420a37bb9e1d1b07edfe419a2" id="a6f6a659420a37bb9e1d1b07edfe419a2"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) void evt\_stop\_timer

Deletes a timer.

Stops a timer and free associated resources.

**Parameters**

**handle** Timer handle acquired by evt\_start\_timer().

### evt\_wait() <a href="#adb08919483f2094f1927d67dad595278" id="adb08919483f2094f1927d67dad595278"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_wait

Wait for a single event.

Stops thread execution till 'event' is received or time specified by 'timeout' is up.

**Parameters**

**event** An Event to wait for. **timeout** A valid wait timeout (timeout > 0) in ms. EVT\_INFINITE\_WAIT - for infinite wait.

#### Returns

Negative: error with errno value. 0: [Event](#struct_event) successfully received. Positive: ETIME - on timeout.

### evt\_wait\_by\_handle() <a href="#a57f2c3182b0ea176490a1735324de25e" id="a57f2c3182b0ea176490a1735324de25e"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_wait\_by\_handle

Blocks thread execution until waiter receive an event or timeout occurs.

Function returns only if event is received or timeout occurred

**Parameters**

**waiter** A handle created by evt\_init\_waiter(). Passing here a destroyed handle cause an undefined behavior. **timeout** A valid wait timeout (timeout > 0) in ms. EVT\_INFINITE\_WAIT - for infinite wait. **policy** WaitPolicy for event group.

#### Returns

ETIME: timeout occurred 0: event received

### evt\_wait\_group() <a href="#ab26c08b8228d47a7b83144e5ec6d9c4e" id="ab26c08b8228d47a7b83144e5ec6d9c4e"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int evt\_wait\_group

Wait for a group of events.

Stops thread execution till one or all (see 'policy') 'events' are received or time specified by 'timeout' is up.

**Parameters**

**events** Array of Events to wait for. Caller is responsible to provide only unique ID. **count** Number of events represented in 'events' param. **timeout** A valid wait timeout (timeout > 0) in ms. EVT\_INFINITE\_WAIT - for infinite wait. **policy** WaitPolicy for event group.

#### Returns

Negative: error with errno value. 0: [Event](#struct_event) successfully received. Positive: ETIME - on timeout.

### get\_dock\_sts() <a href="#adc9d1c34c7762b01b3b9830f1f70c6ed" id="adc9d1c34c7762b01b3b9830f1f70c6ed"></a>

\[EVT\_API]\(#a7e6311173510f4660ef3c2d2f234f429) int get\_dock\_sts

Returns unit dock status.

#### Returns

0: Unit is docked -1: Unit is undocked.

### VariableDocumentation <a href="#variable-documentation" id="variable-documentation"></a>

### EVT\_ANY\_HANDLE <a href="#a63090fb17900201d2517be5e555b7d87" id="a63090fb17900201d2517be5e555b7d87"></a>

const long EVT\_ANY\_HANDLE = -1

Timer [Event](#struct_event) mask that allow to receive all timer events.

### EVT\_DATA\_SIZE <a href="#adb6493cdff512931871b2239b71215c2" id="adb6493cdff512931871b2239b71215c2"></a>

const uint32\_t EVT\_DATA\_SIZE = 64

Size of [Event](#struct_event) additional data.

### EVT\_INFINITE\_WAIT <a href="#a35fc755ca0569e2acb759e0d683a2fb5" id="a35fc755ca0569e2acb759e0d683a2fb5"></a>

const int EVT\_INFINITE\_WAIT = -1

Timeout value for infinite wait.

### EVT\_INVALID\_HANDLE <a href="#a468c3786a00e38b1d61d083fa0b4ce96" id="a468c3786a00e38b1d61d083fa0b4ce96"></a>

const \[WaiterHandle]\(#a7ba4b46d2481427f399dda29a67aaab6) EVT\_INVALID\_HANDLE = 0

Invalid WaiterHandle value.

### EVT\_MAX\_COUNT <a href="#ac34c5452c5be1c370c9c3bf70044d4e0" id="ac34c5452c5be1c370c9c3bf70044d4e0"></a>

const uint32\_t EVT\_MAX\_COUNT = 256

Maximal event count to wait for.


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