qa.hlp (Table of Contents; Topic list)
Int 21H Function 46H
   Summary  Notes  Back
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▀ If the handle passed in CX already refers to an open file, that file is
  closed first.
 
▀ A seek, read, or write operation that moves the file pointer for one of
  the two handles also moves the file pointer associated with the other.
 
▀ This function is commonly used to redirect the standard input and output
  handles to another file or device before a child process is executed with
  Int 21H Function 4BH.
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