rdev linux command

rdev

rdev [options] [image [value [offset]]]

System administration command. If no arguments are specified, display a line, in /etc/mtab syntax, that describes the root filesystem. Otherwise, change the values of the bytes in the kernel image that describe the RAM disk size (by default located at decimal byte offset 504 in the kernel), VGA mode (default 506), and root device (default 508). You must specify the kernel image to change and may specify a new value and a different offset.

Options

-o offset

Same as specifying an offset as an argument. The offset is given in decimal.

-r

Behave like ramsize.

-s

Behave like swapdev.

-v

Behave like vidmode.

-R

Behave like rootflags.