It's in the %SYS namespace

Where can I find the Config.Database class?

Config.DatabasesConfig.Database class

https://openexchange.intersystems.com/package/IO-Redirect

s tmpFile = ##class(%FileCharacterStream).%New()
s myf = tmpFile.Filename = ##class(%File).TempFilename("txt")
open myf:("NW") USE myf ZWRITE ^||fruit
CLOSE myf
s tLine = ""
d tmpFile.Rewind()
while ('tmpFile.AtEnd) {
set tLine = tLine_tmpFile.ReadLine()
}
d ##class(%File).Delete(myf)
w tLine