%N pgqid %F $MIR/src/pgqid.f
%D Inquire current device identifier
%B
      SUBROUTINE PGQID (ID)
      INTEGER  ID

 This subroutine returns the identifier of the currently
 selected device, or 0 if no device is selected.  The identifier is
 assigned when PGOPEN is called to open the device, and may be used
 as an argument to PGSLCT.  Each open device has a different
 identifier.

 [This routine was added to PGPLOT in Version 5.1.0.]

 Argument:
  ID     (output) : the identifier of the current device, or 0 if
                    no device is currently selected.
