COM_GETIRQ()
 Determines the interrupt request for a port
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 Syntax

     COM_GETIRQ(<nComPort>) --> nIRQ

 Argument

     <nComPort>  Designates the port (1 to 4) to which the IRQ currently
     in use is delivered.

 Returns

     COM_GETIRQ() returns the IRQ currently in use for the designated port.
     When there are incorrect parameters, the function returns a value of -1.

 Description

     COM_GETIRQ() determines which IRQ is served by the CA-Clipper Tools
     functions for a particular port.  This value corresponds to an internal
     CA-Clipper Tools software setting.  You cannot determine which IRQ is
     using a particular port.

 Examples

     .  Determine the interrupt request for IRQ to COM2:

        ? COM_GETIRQ(2)      // 3

     .  Specify an inaccurate port number:

        ? COM_GETIRQ(5)      // -1