################################################################################ # T? DList available commands ? Lists all available commands. ################################################################################ # Tautoboot DBoot after a delay autoboot [ []] Displays or a default prompt, and counts down seconds before attempting to boot. If is not specified, the default value is 10. ################################################################################ # Tbcachestat DGet disk block cache stats bcachestat Displays statistics about disk cache usage. For debugging only. ################################################################################ # Tboot DBoot immediately boot [] [- ...] Boot the system. If arguments are specified, they are added to the arguments for the kernel. If is specified, and a kernel has not already been loaded, it will be booted instead of the default kernel. ################################################################################ # Techo DEcho arguments echo [-n] [] Emits , with no trailing newline if -n is specified. This is most useful in conjunction with scripts and the '@' line prefix. Variables are substituted by prefixing them with $, eg. echo Current device is $currdev will print the current device. ################################################################################ # Theap DDisplay memory management statistics heap Requests debugging output from the heap manager. For debugging use only. ################################################################################ # Thelp DDisplay command help help [topic [subtopic]] help index The help command displays help on commands and their usage. In command help, a term enclosed with <...> indicates a value as described by the term. A term enclosed with [...] is optional, and may not be required by all forms of the command. Some commands may not be available. Use the '?' command to list most available commands. ################################################################################ # Tinclude DRead commands from a script file include [ ...] The entire contents of are read into memory before executing commands, so it is safe to source a file from removable media. ################################################################################ # Tload DLoad a kernel or module load [-t ] Loads the module contained in into memory. If no other modules are loaded, must be a kernel or the command will fail. If -t is specified, the module is loaded as raw data of , for later use by the kernel or other modules. may be any string. ################################################################################ # Tls DList files ls [-l] [] Displays a listing of files in the directory , or the root directory of the current device if is not specified. The -l argument displays file sizes as well; the process of obtaining file sizes on some media may be very slow. ################################################################################ # Tlsdev DList devices lsdev [-v] List all of the devices from which it may be possible to load modules. If -v is specified, print more details. ################################################################################ # Tlsmod DList modules lsmod [-v] List loaded modules. If [-v] is specified, print more details. ################################################################################ # Tmore DPage files more [ ...] Show contents of text files. When displaying the contents of more, than one file, if the user elects to quit displaying a file, the remaining files will not be shown. ################################################################################ # Tpnpscan DScan for PnP devices pnpscan [-v] Scan for Plug-and-Play devices. This command is normally automatically run as part of the boot process, in order to dynamically load modules required for system operation. If the -v argument is specified, details on the devices found will be printed. ################################################################################ # Tread DRead input from the terminal read [-t ] [-p ] [] The read command reads a line of input from the terminal. If the -t argument is specified, it will return nothing if no input has been received after seconds. (Any keypress will cancel the timeout). If -p is specified, is printed before reading input. No newline is emitted after the prompt. If a variable name is supplied, the variable is set to the value read, less any terminating newline. ################################################################################ # Treboot DReboot the system reboot Causes the system to immediately reboot. ################################################################################ # Tset DSet a variable set set = The set command is used to set variables. ################################################################################ # Tset Sautoboot_delay DSet the default autoboot delay set autoboot_delay= Sets the default delay for the autoboot command to seconds. Set value to -1 if you don't want to allow user to interrupt autoboot process and escape to the loader prompt. ################################################################################ # Tset Sboot_askname DPrompt for root device set boot_askname Instructs the kernel to prompt the user for the name of the root device when the kernel is booted. ################################################################################ # Tset Sboot_cdrom DMount root file system from CD-ROM set boot_cdrom Instructs the kernel to try to mount the root file system from CD-ROM. ################################################################################ # Tset Sboot_ddb DDrop to the kernel debugger (DDB) set boot_ddb Instructs the kernel to start in the DDB debugger, rather than proceeding to initialize when booted. ################################################################################ # Tset Sboot_dfltroot DUse default root file system set boot_dfltroot Instructs the kernel to mount the statically compiled-in root file system. ################################################################################ # Tset Sboot_gdb DSelect gdb-remote mode for the kernel debugger set boot_gdb Selects gdb-remote mode for the kernel debugger by default. ################################################################################ # Tset Sboot_multicons DUse multiple consoles set boot_multicons Enables multiple console support in the kernel early on boot. In a running system, console configuration can be manipulated by the conscontrol(8) utility. ################################################################################ # Tset Sboot_mute DMute the console set boot_mute All console output is suppressed when console is muted. In a running system, the state of console muting can be manipulated by the conscontrol(8) utility. ################################################################################ # Tset Sboot_pause DPause after each line during device probing set boot_pause During the device probe, pause after each line is printed. ################################################################################ # Tset Sboot_serial DUse serial console set boot_serial Force the use of a serial console even when an internal console is present. ################################################################################ # Tset Sboot_single DStart system in single-user mode set boot_single Prevents the kernel from initiating a multi-user startup; instead, a single-user mode will be entered when the kernel has finished device probes. ################################################################################ # Tset Sboot_verbose DVerbose boot messages set boot_verbose Setting this variable causes extra debugging information to be printed by the kernel during the boot phase. ################################################################################ # Tset Sbootfile DSet the default boot file set set bootfile=[;...] Sets the default set of kernel boot filename(s). It may be overridden by setting the bootfile variable to a semicolon-separated list of filenames, each of which will be searched for in the module_path directories. The default bootfile set is "kernel". ################################################################################ # Tset Sconsole DSet the current console set console[=] Sets the current console. If is omitted, a list of valid consoles will be displayed. ################################################################################ # Tset Scurrdev DSet the current device set currdev= Selects the default device. See lsdev for available devices. ################################################################################ # Tset Sinit_path DSet the list of init candidates set init_path=[:...] Sets the list of binaries which the kernel will try to run as initial process. ################################################################################ # Tset Smodule_path DSet the module search path set module_path=[;...] Sets the list of directories which will be searched in for modules named in a load command or implicitly required by a dependency. The default module_path is "/boot/modules" with the kernel directory prepended. ################################################################################ # Tset Snum_ide_disks DSet the number of IDE disks NOTE: this variable is deprecated, use root_disk_unit instead. set num_ide_disks= When booting from a SCSI disk on a system with one or more IDE disks, and where the IDE disks are the default boot device, it is necessary to tell the kernel how many IDE disks there are in order to have it correctly locate the SCSI disk you are booting from. ################################################################################ # Tset Sprompt DSet the command prompt set prompt= The command prompt is displayed when the loader is waiting for input. Variable substitution is performed on the prompt. The default prompt can be set with: set prompt=\${interpret} ################################################################################ # Tset Sroot_disk_unit DForce the root disk unit number. set root_disk_unit= If the code which detects the disk unit number for the root disk is confused, eg. by a mix of SCSI and IDE disks, or IDE disks with gaps in the sequence (eg. no primary slave), the unit number can be forced by setting this variable. ################################################################################ # Tset Srootdev DSet the root filesystem set rootdev= By default the value of $currdev is used to set the root filesystem when the kernel is booted. This can be overridden by setting $rootdev explicitly. ################################################################################ # Tset Stunables DSet kernel tunable values Various kernel tunable parameters can be overridden by specifying new values in the environment. set kern.ipc.nmbclusters= Set the number of mbuf clusters to be allocated. The value cannot be set below the default determined when the kernel was compiled. set kern.ipc.nsfbufs= NSFBUFS Set the number of sendfile buffers to be allocated. This overrides the value determined when the kernel was compiled. set vm.kmem_size= VM_KMEM_SIZE Sets the size of kernel memory (bytes). This overrides the value determined when the kernel was compiled. set machdep.disable_mtrrs=1 Disable the use of i686 MTRRs (i386 only) set net.inet.tcp.tcbhashsize= TCBHASHSIZE Overrides the compile-time set value of TCBHASHSIZE or the preset default of 512. Must be a power of 2. hw.syscons.sc_no_suspend_vtswitch= Disable VT switching on suspend. value is 0 (default) or non-zero to enable. set hw.physmem= MAXMEM (i386 only) Limits the amount of physical memory space available to the system to bytes. may have a k, M or G suffix to indicate kilobytes, megabytes and gigabytes respectively. Note that the current i386 architecture limits this value to 4GB. On systems where memory cannot be accurately probed, this option provides a hint as to the actual size of system memory (which will be tested before use). set hw.{acpi,pci}.host_start_mem= Sets the lowest address that the pci code will assign when it doesn't have other information about the address to assign (like from a pci bridge). This is only useful in older systems without a pci bridge. Also, it only impacts devices that the BIOS doesn't assign to, typically CardBus bridges. The default is 0x80000000, but some systems need values like 0xf0000000, 0xfc000000 or 0xfe000000 may be suitable for older systems (the older the system, the higher the number typically should be). set hw.pci.enable_io_modes= Enable PCI resources which are left off by some BIOSes or are not enabled correctly by the device driver. value is 1 (default), but this may cause problems with some peripherals. Set to 0 to disable. ################################################################################ # Tshow DShow the values of variables show [] Displays the value of , or all variables if not specified. Multiple paths can be separated with a semicolon. ################################################################################ # Tsmap DDisplay BIOS SMAP table smap Displays the BIOS SMAP (system memory map) table. ################################################################################ # Tunload DRemove all modules from memory unload This command removes any kernel and all loaded modules from memory. ################################################################################ # Tunset DUnset a variable unset If allowed, the named variable's value is discarded and the variable is removed. ################################################################################