IBM TS2340 User Guide - Page 165

Solaris Device Driver (IBMtape) File Naming Conventions Table 28 shows the special file naming convention and the associated device attributes recognized by the IBMtape device driver. Table 28. IBM SCSI Tape/Medium Changer Special Files for Solaris Special File Name BSD Compatibility (Note 1) Rewind on Close (Note 2) Compression (Note 3) /dev/rmt/[0-255]smc (Note 4) N/A N/A N/A /dev/rmt/[0-255]stn (Note 5) No No No /dev/rmt/[0-255]stcn (Note 5) No No Yes /dev/rmt/[0-255]st (Note 5) No Yes No /dev/rmt/[0-255]stc (Note 5) No Yes Yes /dev/rmt/[0-255]stbn (Note 5) Yes /dev/rmt/[0-255]stcbn (Note 5) Yes No No No Yes /dev/rmt/[0-255]stb (Note 5) Yes Yes No /dev/rmt/[0-255]stcb (Note 5) Yes Yes Yes Notes: 1. The BSD (b) device special file modifies close behavior for non-rewind devices. If the device is opened for no rewind on close in non-BSD mode, and if the last command before closing the device was a read, then the tape is positioned after the filemark immediately following the last block read. If the device is opened for no rewind on close in BSD mode, and if the last command before closing the device was a read, the tape is left positioned exactly where it was following the last block read. If the device is opened for rewind on close the BSD mode is not relevant. 2. The no rewind on close (n) device special file does not rewind the tape during a close operation. Otherwise, the tape is rewound when the device is closed. If the last operation before closing the device was a write or write filemark, then a sufficient number of filemarks is written so that two filemarks follow the data. For the non-rewind special files, the tapes are positioned between the trailing filemarks before closing. If the device is then reopened and more data is written, it is separated by a single filemark from the previous data. 3. The compression (c) device special file determines whether the tape device uses built-in hardware compression while storing data on the tape. The compression mode of the device can also be set to the desired state programmatically through the STIOC_SET_PARM ioctl, regardless of the default compression mode established by the special file originally used to open the device. 4. The smc special file is created only for IBM tape systems that provide medium changer capability. For IBM tape libraries and autoloaders, the smc special file is the only file created because the IBMtape device driver supports only the medium changer portion and does not support the tape drive portion of these devices. For the IBM 3490E Magnetic Tape System, there is no smc special file created. 5. Only one st special file may be opened at one time. The smc special file may be opened by itself or in conjunction with one of the st type files. The smc special file accepts only medium changer commands. Tape drive commands issued to the medium changer fail, with errno set to 22, invalid argument. Aside from the normal configuration with the medium changer answering as a distinct target/LUN pair, some supported devices can be configured with a nonstandard integrated medium changer reporting at the same target and LUN as the tape drive. In such a case, both st and smc special files accept a limited subset of medium changer commands. If you want to use this nonstandard mode, consult the appropriate hardware reference to determine whether the drive supports such a configuration. Chapter 6. Solaris Tape and Medium Changer Device Driver 147