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$ZIO (ObjectScript)

Contains information about the current terminal I/O device.




$ZIO contains information about the current I/O device.

For a terminal device that is a Terminal, $ZIO contains the string TRM:. If the current terminal device is connected remotely, $ZIO contains information about the remote connection.

For a terminal device connected through TELNET, $ZIO contains the following: host|port:

Argument Description
host The remote host IP address, in either IPv4 format:nnn.nnn.nnn.nnn, where nnn is a decimal number, or in IPv6 format: h:h:h:h:h:h:h:h, where h is a hexadecimal number. Further details on IPv4 and IPv6 formats can be found in Use of IPv6 Addressing.
port The remote IP port number.

These two values are separated by a vertical bar character. For example,|23. For further information, refer to the %Library.NetworkAddressOpens in a new tab class, a subclass of the data type class %Library.StringOpens in a new tab.

If the current device is not a terminal:

  • If a file, $ZIO contains the full canonical pathname of the file.

  • If not a file, $ZIO contains the null string.

The following example returns the current device information:

   SET x=$CASE($ZIO,"TRM:":"a terminal",
               "CON:":"a console",
               "":"neither terminal nor file")
   WRITE "The current device is ",x

This special variable cannot be modified using the SET command. Attempting to do so results in a <SYNTAX> error.

See Also

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