I don't know the datatype, the help says:
Quote: "ENTRY$
This command will return the string currently held by the windows system. This string is maintained by the windows message pump and ensures you do not miss characters typed at speed in your application. You can clear this string using the CLEAR ENTRY BUFFER command. The entry buffer command automatically handles the collection of text typed in by the end user. By proving the extra parameter in the command ENTRY$(1) the system will automatically delete characters if the backspace key is pressed.
Syntax
Return String=ENTRY$()
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