NAME

	chdev – change kernel driver access

SYNOPSIS

	chdev [ –nr ] devmask...

DESCRIPTION

Chdev modifies access to kernel drivers for the current process and processes within the same name group (see fork(2)). Access is defined as the ability for a process to walk files and directories served by the driver through its location within '#'. Existing binds of drivers are left unaffected. Access may only be removed; after a specific driver is ejected no further operations can permit access again. Access is inherited by all children of the name group, regardless if the child has elected to receive a clean namespace. Devmask is a string of driver characters. The default behavior is to block access to all but the listed drivers. Flags provide a way to modify this behavior: –r    Retain access to all but the specified drivers. –n    Remove access to all drivers. Devmask is ignored. Access to some drivers is tied to other related process capabilities: mnt(3) Ability to perform the mount(2) system call, and to post new services to shr(3). pipe(3) Ability to perform the pipe(2) system call.

EXAMPLES

	Permit access to only draw(3), rtc(3), fs(3), and srv(3): chdev irks Remove access to cons(3), rtc(3), audio(3), and proc(3): chdev –r crAp Create a pipe(3) then remove the ability to create more: bind '#|' /n/pipe chdev –r '|'

SOURCE

	/rc/bin/chdev

SEE ALSO

	/dev/drivers for a list of current drivers. intro(3), cons(3)

DIAGNOSTICS

	Chdev is implemented through writes to /dev/drivers, served by cons(3).

HISTORY

	Chdev first appeared in 9front (May, 2022).