DOS Fn 3eH: Close a File Handle

                                                         Compatibility: 2.0+ 
 Expects: AH    3eH
          BX    file handle
 Returns: AX    error code if CF is set to CY
    Info: Closes an open file.

       BX contains a file handle returned from an Open operation.  The file
          represented by that handle is closed, its buffers are flushed,
          and the directory is updated with the correct size, time, and

          Because of the potential shortage of file handles (default=8,
          max=20 with DOS < 3.3), you may want to close one or more of the
          default handles, such as handle 3 (Standard AUX).

   Notes: ■ Smartdrv may decide not to flush its cache for up to several
            seconds.  To force "commit" to disk, use Fn 0dH (reset disk)
            after closing the file.

          ■ With DOS 3.3+, you can force a "commit to disk" without closing
            the file.  See Fn 68H (commit file).

See Also: Handle-Oriented File I/O
          DOS Functions