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ZBC(8) System Manager's Manual ZBC(8)


zbc_read_zone - Read sectors of a zone of a ZBC or ZAC device


zbc_read_zone [options] device zone_number IO_size


zbc_read_zone is used to read sectors from a zone of a ZBC or ZAC device. By default, the target zone will be read starting from the first sector of the zone. For sequential zones, the default behavior is to read all sectors up to the zone write pointer position. For conventional zones, all sectors are read.

The device argument must be the pathname to the target device block device file (e.g., /dev/sdb), or to the target device SG node file (e.g., /dev/sg3). On old kernels lacking ZBC and ZAC support, only the device SG node file will be available.


The following options can be specified.

Display a usage help message and exit.
Verbose mode (for debugging problems).
Use direct IO operations.
Use vectored IO with num buffers of IO_size bytes, resulting in an actual I/O size of num x IO_size bytes.
Limit the number of I/O executed to num.
Expect all bytes that are read to have the value num. In case of a mismatch, the offset of the bytes with the incorrect value is printed.
Write the data read from the zone to file. If file is "-", the data read is printed to the standard output.
Read the zone from the sector offset ofst instead of from the start of the zone.


Damien Le Moal <>


dd(1), sg_dd(8)


The zbc_read_zone utility is part of the libzbc library available from