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    CallAck

    2026-11-06
    POST

    https://zim-api.zego.im/

    This API sends a delivered receipt for an offline call invitation on behalf of a user.

    After the user accepts the invitation and enters the call, other users in the call will receive a notification of the call user status change through the following ZIM SDK callback:

    iOSAndroidmacOSWindows
    callUserStateChangedonCallUserStateChangedcallUserStateChangedonCallUserStateChanged
    WebFlutterReact NativeUnity3D
    onCallUserStateChangedonCallUserStateChangedonCallUserStateChangedOnCallUserStateChanged
    QPS Limit
    20 requests/s

    Request

    Query Parameters

      Action stringrequired

      Possible values: [CallAck]

      API prototype parameter

      https://zim-api.zego.im/?Action=CallAck

      AppId uint32required

      💡Public parameter. Application ID, assigned by ZEGOCLOUD. Get it from the ZEGOCLOUD Admin Console.

      SignatureNonce stringrequired

      💡Public parameter. A 16-character hexadecimal random string (hex encoding of 8-byte random number). Refer to Signature example for how to generate.

      Timestamp int64required

      💡Public parameter. Current Unix timestamp, in seconds. Refer to Signature example for how to generate, with a maximum error of 10 minutes.

      SignatureVersion stringrequired

      Possible values: [3.0]

      Default value: 3.0

      💡Public parameter. Signature version.

      Signature stringrequired

      💡Public parameter. Signature, used to verify the legitimacy of the request. Refer to Signing the requests for how to generate an API request signature.

    Body

    required
      FromUserId stringrequired

      Possible values: <= 32 characters

      The user ID of the operator (the recipient of the call invitation). The user must be registered and must be a callee in this call.

      CallId stringrequired

      Possible values: <= 32 characters

      The call ID returned by the API that created the call.

    Responses​

    OK
    Schema
      Code integer

      Return code. 0 indicates success.

      The following table lists only the return codes related to this API's business logic. For the complete list, see Return codes.

      Return codeDescriptionSuggested actions
      660000002Invalid parameters.Check the parameters.
      660300005Rate limit exceeded.Try again later.
      660900004The call could not be retrieved or has ended.Check CallId and the call status.
      660900008The user is not a member of this call.Check whether FromUserId is a callee in the call.
      Message string

      Response status information.

      RequestId string

      Unique request identifier.

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