ref: fdcf0addac46643c8924e57992adb7f66c992b33
dir: /sys/man/1/chdev/
.TH CHDEV 1 .SH NAME chdev \- change kernel driver access .SH SYNOPSIS .B chdev [ -nr ] \f2devmask\fP... .SH DESCRIPTION .I Chdev modifies access to kernel drivers for the current process and processes within the same name group (see .IR 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. .PP 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. .PP .IR 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: .TP .B -r Retain access to all but the specified drivers. .TP .B -n Remove access to all drivers. .I Devmask is ignored. .PP Access to some drivers is tied to other related process capabilities: .TP \f2mnt\fP(3) .IP Ability to perform the .IR mount (2) system call, and to post new services to .IR shr (3). .TP \f2pipe\fP(3) .IP Ability to perform the .IR pipe (2) system call. .SH EXAMPLES Permit access to only .IR draw (3), .IR rtc (3), .IR fs (3), and .IR srv (3): .IP .EX chdev irks .EE .PP Remove access to .IR cons (3), .IR rtc (3), .IR audio (3), and .IR proc (3): .IP .EX chdev -r crAp .EE .PP Create a .IR pipe (3) then remove the ability to create more: .IP .EX bind '#|' /n/pipe chdev -r '|' .EE .SH SOURCE .B /rc/bin/chdev .SH "SEE ALSO" .B /dev/drivers for a list of current drivers. .PP .IR intro (3), .IR cons (3) .SH DIAGNOSTICS .I Chdev is implemented through writes to .BR /dev/drivers , served by .IR cons (3). .SH HISTORY Chdev first appeared in 9front (May, 2022).