CONTROL
- Introduction to CTRL
- CONTROL Classes
- Types of Control Functions
- CONTROL graphics
- CONTROL Functions
  - Funtions A
  - Funtions B
  - Funtions C
  - Funtions D
  - Functions E
    - exit()
      Terminates a manager and passes the exit code to the operating system.
    - errorDialog()
      Displays an error dialog.
    - ecdhGetPublicKey()
      The function stores the public key of the key pair for the ECDH key exchange.
    - errorText()
      Returns the text for the error code. This function should not be used anymore but remains included for reasons of compatibility. Instead of this function, use the functions getCatStr() or getErrorText(). These functions allow the definition of own error messages dependent on specific error codes. The error codes are saved in the file _errors.cat in the directory <wincc_oa_path>/msg/<lang>, respectively in the same file in the project directory.
    - ecdhDeriveSharedSecret()
      Generates a shared secret based on the key pair for an ECDH key exchange.
    - enumValues()
      The function returns the values of an enumeration as mapping.
    - execJsFunction()
      The function allows to call a JavaScript function from within the WebView EWO JavaScript code directly from CTRL.
    - eventPort()
      Returns the port number of the Event manager.
    - enableSound()
      Switches the sound of a wave file during runtime (see Configuration file).
    - execScriptRestricted()
      This function, like execScript(), allows for execution of a script during runtime. Use this function to run void main-functions which have no return value. Contrasting to execScript() the functions that can be used inside the executed script are limited to provide better security against insertion of malicious code.
    - ecdhReleaseKeyPair()
      The function releases a private/public key pair for an ECDH key exchange.
    - emSendMail() - obsolete
      This function allows sending mails.
    - execJsFunctionDyn()
      The function allows to call a JavaScript function from within the WebView EWO JavaScript code directly from CTRL.
    - evalScript()
      Allows to execute a script during runtime and to write the return value of the script in retVal.
    - enableMenuItem() - obsolete
      Supports disabling of menus (obsolete from version 3.5 up).
    - execScript()
      Allows to execute a script during runtime. Use this function for void main-functions (without return value).
    - emRetrieveMail()
      The function connects to a POP3 server and checks wether there are mails. If there are, the function retrieves the mails and deletes the mail at the server.
    - enumKeys()
      The function returns the list of keys that are available within the enumeration.
    - exp()
      Exponential function
    - eventHost()
      Returns the host name the event manager is running on.
    - evalScriptRestricted()
      Allows to execute a script during runtime and to write the return value of the script in target. Compared to the unrestricted function evalScript() only a more limited set of functions is allowed to provide better security.
    - ecdhGenerateKeyPair()
      The function generates a random private/public key pair for an ECDH key exchange.
  - Functions F
  - Functions G
  - Functions H
  - Functions I
  - Functions J
  - Functions K
  - Functions L
  - Functions M
  - Functions N
  - Functions O
  - Functions P
  - Functions Q
  - Functions R
  - Functions S
  - Functions T
  - Functions U
  - Functions V
  - Functions W
  - Functions X
  - Functions Y
  - Functions Z
- CTRL Debugger
  With the CTRL Debugger you can debug the programming language Control.

eventHost()

Returns the host name the event manager is running on.

Synopsis

dyn_string eventHost();

Parameters

None

Return value

dyn_string (in a single system the host the Event Manager is running on and an empty string). In a redundant system the function returns the left and the right computer.

in a redundant System:

[1] = Left Event

[2] = Right Event

In a non-redundant system:

[1] = event

[2] = "" (empty string)

Description

Returns the host name. In a single system, the function returns the name of the host the Event Manager is running on as well as an empty string. In a redundant system, the function returns the left and right computers (the System Management- Diagnostics-System overview displays the left and the right computer if your system is redundant).

Example

main()
{
   dyn_string host;
   host = eventHost();
   DebugN(host);
}

Assignment

Miscellaneous functions

Availability

CTRL