40 lines
1,022 B
C
40 lines
1,022 B
C
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/*************************************************************************
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*
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* tape390.h
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* enables user programs to display messages on the tape device
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*
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* S390 and zSeries version
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* Copyright (C) 2001 IBM Corporation
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* Author(s): Despina Papadopoulou <despina_p@de.ibm.com>
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*
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*************************************************************************/
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#ifndef _TAPE390_H
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#define _TAPE390_H
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#define TAPE390_DISPLAY _IOW('d', 1, struct display_struct)
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/*
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* The TAPE390_DISPLAY ioctl calls the Load Display command
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* which transfers 17 bytes of data from the channel to the subsystem:
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* - 1 format control byte, and
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* - two 8-byte messages
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*
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* Format control byte:
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* 0-2: New Message Overlay
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* 3: Alternate Messages
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* 4: Blink Message
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* 5: Display Low/High Message
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* 6: Reserved
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* 7: Automatic Load Request
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*
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*/
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typedef struct display_struct {
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char cntrl;
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char message1[8];
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char message2[8];
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} display_struct;
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#endif
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