NAME    [Toc]    [Back]

     bio - ioctl tunnel pseudo-device

SYNOPSIS    [Toc]    [Back]

     pseudo-device bio [count]

DESCRIPTION    [Toc]    [Back]

     The bio driver provides userland applications  ioctl  access
to devices
     otherwise not found as /dev nodes.  The /dev/bio device node
operates by
     delegating ioctl(2) calls to a requested device driver.  Only drivers
     which  have  registered  with the bio device can be accessed
via this interface.


     If count is given in the specification, and is greater  than
0, a maximum
     of one bio device is created.

     The following ioctl(2) calls apply to the bio device:

     BIOCLOCATE   Locate a named device and give back a cookie to
the application
 for subsequent ioctl calls.  The cookie  is
used to tunnel
 further ioctls to the right device.

FILES    [Toc]    [Back]

     /dev/bio  ioctl tunnel device

SEE ALSO    [Toc]    [Back]

     ioctl(2), gdt(4)

HISTORY    [Toc]    [Back]

     The bio driver first appeared in OpenBSD 3.2.

OpenBSD      3.6                           June      8,      2002