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Sockets, Channels, File Descriptors?

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The Question is:

I have vendor software that is returning the UNIX I/O file descriptor to a
 terminal port. I need to provide the VMS QIO call to change the baud rate of
 the channel since the POSIX tcsetattr function is not implemented. The problem
 is that the QIO requires
 the VMS channel number, not the file descriptor. I've searched all of the C
 manuals for converting file descriptor to channel but it seems the only
 conversion is the special socket descriptor to channel . I tried that in case
 socket descriptors were similar enough to file descriptors but found that it
 didn't work. I also pursured the conversions from file descriptors to file
 pointers with no luck. Is there any way to convert a file descriptor to VMS

The Answer is :

  There is normally no need to perform this translation, as you can open
  a second and new channel to the terminal device (from a process with
  SHARE privilege enabled).  Make certain that you deassign any channel
  that was opened via use of SHARE privilege prior to deassigning the
  original I/O channel.

answer written or last revised on ( 6-NOV-2000 )

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