jBASE provides support for the following tape devices. The device control records are located in the "dev" subdirectory of the jBASE release directory.
The actual tape device files on Unix reside in the "/dev/rmt" directory, however naming conventions differ between the various different platforms.
The actual tape devices on NT are named by convention \\.\TAPE0, etc. Where as the floppy disc is named as \\.\A:
Note: Windows 95 does not support tape devices via the Win32 standard interface. However jBASE has been enabled to read and write to the Win95 floppy disc drive.
Compression and formats can vary between different manufacturers of the same device. When reading or writing a tape ensure that the target system device is compatible with your format of written media.
QIC 150 and QIC 525 appear to be readable by most Stream cartridge tape drives. In general higher specification drives tend to be able to read, but not necessarily write, lower specification media tapes.
Note: Some DAT devices must be enabled for variable length blocks before they can be read else they produce no data status. This can also happen when the requested block size is lower than the actual block size on tape.
To enable variable length tape on SVR4 systems use the following command.
On AIX use "smitty" to set tape device for variable length.
The Label and block size parameters can be overridden from the T-ATT command line. For instance to attach and read a tape blocked at 5120, i.e. a tar, use the following command.
To read a tape produced by R83 use the following command.
The -2 means the label is expected to be the same block size as the other tape blocks. To read a tape produced by a ROS system use the following command.
Note: Streaming cartridge drives automatically pad to 512 byte boundary on write.