/************************************************************************* * * tape390.h * enables user programs to display messages on the tape device * * S390 and zSeries version * Copyright (C) 2001 IBM Corporation * Author(s): Despina Papadopoulou <despina_p@de.ibm.com> * *************************************************************************/ #ifndef _TAPE390_H #define _TAPE390_H #define TAPE390_DISPLAY _IOW('d', 1, struct display_struct) /* * The TAPE390_DISPLAY ioctl calls the Load Display command * which transfers 17 bytes of data from the channel to the subsystem: * - 1 format control byte, and * - two 8-byte messages * * Format control byte: * 0-2: New Message Overlay * 3: Alternate Messages * 4: Blink Message * 5: Display Low/High Message * 6: Reserved * 7: Automatic Load Request * */ typedef struct display_struct { char cntrl; char message1[8]; char message2[8]; } display_struct; #endif