User  |  Syst  |  Libr  |  Device  |  Files  |  Other  |  Admin  |  Head  |

---

   blockdev    ( 8 )

---

---

Имя (Name)

blockdev - call block device ioctls from the command line

---

Синопсис (Synopsis)

blockdev [-q] [-v] command [command...] device [device...]

blockdev --report [device...]

blockdev -h|-V

---

Описание (Description)

The utility blockdev allows one to call block device ioctls from the command line.

---

Параметры (Options)

-q
           Be quiet.

       -v
           Be verbose.

       --report
           Print a report for the specified device. It is possible to
           give multiple devices. If none is given, all devices which
           appear in /proc/partitions are shown. Note that the partition
           StartSec is in 512-byte sectors.

       -h, --help
           Display help text and exit.

       -V, --version
           Print version and exit.

---

Команды (Commands)

It is possible to give multiple devices and multiple commands.

--flushbufs Flush buffers.

--getalignoff Get alignment offset.

--getbsz Print the blocksize in bytes. This size does not describe device topology. It's the size used internally by the kernel and it may be modified (for example) by filesystem driver on mount.

--getdiscardzeroes Get discard zeroes support status.

--getfra Get filesystem readahead in 512-byte sectors.

--getiomin Get minimum I/O size.

--getioopt Get optimal I/O size.

--getmaxsect Get max sectors per request.

--getpbsz Get physical block (sector) size.

--getra Print readahead (in 512-byte sectors).

--getro Get read-only. Print 1 if the device is read-only, 0 otherwise.

--getsize64 Print device size in bytes.

--getsize Print device size (32-bit!) in sectors. Deprecated in favor of the --getsz option.

--getss Print logical sector size in bytes - usually 512.

--getsz Get size in 512-byte sectors.

--rereadpt Reread partition table

--setbsz bytes Set blocksize. Note that the block size is specific to the current file descriptor opening the block device, so the change of block size only persists for as long as blockdev has the device open, and is lost once blockdev exits.

--setfra sectors Set filesystem readahead (same as --setra on 2.6 kernels).

--setra sectors Set readahead (in 512-byte sectors).

--setro Set read-only. The currently active access to the device may not be affected by the change. For example, a filesystem already mounted in read-write mode will not be affected. The change applies after remount.

--setrw Set read-write.

---