IBM TS2340 User Guide - Page 125

Special Files, Special Files for the Tape Device, Trailer Labels

Page 125 highlights

Linux Device Driver (lin_tape) Trailer Labels If this parameter is set to On, then writing records past the early warning mark on the tape is allowed. The first write operation after detecting the early warning mark fails and the errno variable is set to ENOSPC. No data is written during the operation. All subsequent write operations are allowed to continue until the physical end of the volume is reached and errno EIO is returned. If this parameter is set to Off, then writing records past the early warning mark is not allowed. Errno variable is set to ENOSPC. The installation default is On (with trailer labels). Special Files After the driver is installed and a device is configured and made available for use, access is provided through the special files. These special files, which consist of the standard Linux special files for devices, are in the /dev directory. Special Files for the Tape Device Each tape device has a set of special files providing access to the same physical drive but providing different attributes. Table 18 shows the attributes of the special files. Note: The asterisk (*) in IBMtape* represents a number assigned to a particular device, such as IBMtape0. For tape drives with attached medium changer devices, the IBMchanger* special file provides a separate path for issuing commands to the medium changer. When this special file is opened, the application can view the medium changer as a separate device. Both the tape and changer special file can be opened at the same time. Table 18. Special Files for IBM TotalStorage Tape Devices Special File Name /dev/IBMTape* /dev/IBMTape*n Rewind on Close YES NO Special Files for the Medium Changer Device After the driver is installed and a medium changer device is configured and made available for use, access to the robotic device is provided through the IBMchanger special file in the /dev directory. The asterisk (*) represents a number assigned to a particular device, such as IBMchanger0. The term IBMchanger is used for a SCSI medium changer device. The IBMchanger* special file provides a path for issuing commands to control the medium changer robotic device. The file descriptor that results from opening the IBMchanger special file does not support the following operations: v Read v Write v Open in Append mode v Commands designed for a tape device Chapter 5. Linux Tape and Medium Changer Device Driver 107

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Trailer Labels
If this parameter is set to On, then writing records past the early warning mark on
the tape is allowed. The first write operation after detecting the early warning
mark fails and the
errno
variable is set to ENOSPC. No data is written during the
operation. All subsequent write operations are allowed to continue until the
physical end of the volume is reached and
errno
EIO is returned.
If this parameter is set to Off, then writing records past the early warning mark is
not allowed.
Errno
variable is set to ENOSPC.
The installation default is On (with trailer labels).
Special Files
After the driver is installed and a device is configured and made available for use,
access is provided through the special files. These special files, which consist of the
standard Linux special files for devices, are in the
/dev
directory.
Special Files for the Tape Device
Each tape device has a set of special files providing access to the same physical
drive but providing different attributes. Table 18 shows the attributes of the special
files.
Note:
The asterisk (*) in
IBMtape*
represents a number assigned to a particular
device, such as
IBMtape0
.
For tape drives with attached medium changer devices, the
IBMchanger*
special file
provides a separate path for issuing commands to the medium changer. When this
special file is opened, the application can view the medium changer as a separate
device. Both the tape and changer special file can be opened at the same time.
Table18. Special Files for IBM TotalStorage Tape Devices
Special File Name
Rewind on Close
/dev/IBMTape*
YES
/dev/IBMTape*n
NO
Special Files for the Medium Changer Device
After the driver is installed and a medium changer device is configured and made
available for use, access to the robotic device is provided through the
IBMchanger
special file in the
/dev
directory. The asterisk (*) represents a number assigned to a
particular device, such as
IBMchanger0
. The term
IBMchanger
is used for a SCSI
medium changer device. The
IBMchanger*
special file provides a path for issuing
commands to control the medium changer robotic device.
The file descriptor that results from opening the
IBMchanger
special file does not
support the following operations:
v
Read
v
Write
v
Open in Append mode
v
Commands designed for a tape device
Linux Device Driver (lin_tape)
Chapter 5. Linux Tape and Medium Changer Device Driver
107