# File Open

Opens a specified text file.

Action available for the following operating systems:

![](/files/-MAlQBZuuTnc6hyzKSVQ)

### Parameters

* **File ID** *\<numeric> -* The identification to the file that the user wants to open. This File ID will be used along the project to interact with the opened file. It works like an handler to the file.
* **File Name** *\<string> -* The name of the opened file. The user should indicate the full path of the file.

*Details*

* **Opening Mode** *\<unquoted string> -* Indicate the opening mode that user wants to set to this opened file. The possible values for this parameter are: Read, Write, Append (Write) or dynamic. If the user wants to write data in the end of the file, user should choose option Append (Write).
* **Encoding** *\<numeric> - I*ndicates the file encoding to use. It can be one of:
  1. Unicode UTF-16 LE (each character uses 2 bytes)
  2. ANSI/BINARY (each character uses 1 byte)
  3. Unicode UTF-8 (each character uses 1 byte to 4 bytes)

{% hint style="info" %}
In Unicode UTF-16 LE, if the file does not exist, the BOM (Byte Order Mark) 0xFEFF will be added to the beginning of the file. If the file already exists the first 2 bytes must be 0xFEFF.
{% endhint %}

{% hint style="info" %}
In Unicode UTF-8, if the file does not exist, no BOM (Byte Order Mark) will be added. If the file already exists the first 3 bytes may optionally be 0xEFBBBF.
{% endhint %}


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