1 ################################################################################
2 # Thelp DDisplay command help
4 help [topic [subtopic]]
7 The help command displays help on commands and their usage.
9 In command help, a term enclosed with <...> indicates a value as
10 described by the term. A term enclosed with [...] is optional,
11 and may not be required by all forms of the command.
13 Some commands may not be available. Use the '?' command to list
14 most available commands.
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17 # Tautoboot DBoot after a delay
19 autoboot [<delay> [<prompt>]]
21 Displays <prompt> or a default prompt, and counts down <delay> seconds
22 before attempting to boot. If <delay> is not specified, the default
25 ################################################################################
26 # Tboot DBoot immediately
28 boot [<kernelname>] [-<arg> ...]
30 Boot the system. If arguments are specified, they are added to the
31 arguments for the kernel. If <kernelname> is specified, and a kernel
32 has not already been loaded, it will be booted instead of the default
35 ################################################################################
36 # Techo DEcho arguments
40 Emits <message>, with no trailing newline if -n is specified. This is
41 most useful in conjunction with scripts and the '@' line prefix.
43 Variables are substituted by prefixing them with $, eg.
45 echo Current device is $currdev
47 will print the current device.
49 ################################################################################
50 # Tload DLoad a kernel or module
52 load [-t <type>] <filename>
54 Loads the module contained in <filename> into memory. If no other
55 modules are loaded, <filename> must be a kernel or the command will
58 If -t is specified, the module is loaded as raw data of <type>, for
59 later use by the kernel or other modules. <type> may be any string.
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66 Displays a listing of files in the directory <path>, or the root
67 directory of the current device if <path> is not specified.
69 The -l argument displays file sizes as well; the process of obtaining
70 file sizes on some media may be very slow.
72 ################################################################################
73 # Tlsdev DList devices
77 List all of the devices from which it may be possible to load modules.
78 If -v is specified, print more details.
80 ################################################################################
81 # Tlsmod DList modules
85 List loaded modules. If [-v] is specified, print more details.
87 ################################################################################
90 more <filename> [<filename> ...]
92 Show contents of text files. When displaying the contents of more,
93 than one file, if the user elects to quit displaying a file, the
94 remaining files will not be shown.
96 ################################################################################
97 # Tpnpscan DScan for PnP devices
101 Scan for Plug-and-Play devices. This command is normally automatically
102 run as part of the boot process, in order to dynamically load modules
103 required for system operation.
105 If the -v argument is specified, details on the devices found will
108 ################################################################################
109 # Tset DSet a variable
112 set <variable name>=<value>
114 The set command is used to set variables.
116 ################################################################################
117 # Tset Sautoboot_delay DSet the default autoboot delay
119 set autoboot_delay=<value>
121 Sets the default delay for the autoboot command to <value> seconds.
123 ################################################################################
124 # Tset Sbootfile DSet the default boot file set
126 set bootfile=<filename>[;<filename>...]
128 Sets the default set of kernel boot filename(s). It may be overridden
129 by setting the bootfile variable to a semicolon-separated list of
130 filenames, each of which will be searched for in the module_path
131 directories. The default bootfile set is "kernel;kernel.old".
133 ################################################################################
134 # Tset Sboot_askname DPrompt for root device
138 Instructs the kernel to prompt the user for the name of the root device
139 when the kernel is booted.
141 ################################################################################
142 # Tset Sboot_ddb DDrop to the kernel debugger (DDB)
146 Instructs the kernel to start in the DDB debugger, rather than
147 proceeding to initialise when booted.
149 ################################################################################
150 # Tset Sboot_gdb DSelect gdb-remote mode
154 Selects gdb-remote mode for the kernel debugger by default.
156 ################################################################################
157 # Tset Sboot_single DStart system in single-user mode
161 Prevents the kernel from initiating a multi-user startup, single-user
162 mode will be entered when the kernel has finished device probes.
164 ################################################################################
165 # Tset Sboot_verbose DVerbose boot messages
169 Setting this variable causes extra debugging information to be printed
170 by the kernel during the boot phase.
172 ################################################################################
173 # Tset Sconsole DSet the current console
175 set console[=<value>]
177 Sets the current console. If <value> is omitted, a list of valid
178 consoles will be displayed.
180 ################################################################################
181 # Tset Scurrdev DSet the current device
185 Selects the default device. Syntax for devices is odd.
187 ################################################################################
188 # Tset Sinit_path DSet the list of init candidates
190 set init_path=<path>[:<path>...]
192 Sets the list of binaries which the kernel will try to run as initial
196 ################################################################################
197 # Tset Smodule_path DSet the module search path
199 set module_path=<path>[;<path>...]
201 Sets the list of directories which will be searched in for modules
202 named in a load command or implicitly required by a dependency. The
203 default module_path is "/;/boot;/modules".
205 ################################################################################
206 # Tset Sprompt DSet the command prompt
210 The command prompt is displayed when the loader is waiting for input.
211 Variable substitution is performed on the prompt. The default
212 prompt can be set with:
214 set prompt=\$currdev>
216 ################################################################################
217 # Tset Srootdev DSet the root filesystem
221 By default the value of $currdev is used to set the root filesystem
222 when the kernel is booted. This can be overridden by setting
225 ################################################################################
226 # Tset Stunables DSet kernel tunable values
228 Various kernel tunable parameters can be overridden by specifying new
229 values in the environment.
231 set kern.ipc.nmbclusters=<value> NMBCLUSTERS
233 Set the number of mbuf clusters to be allocated. The value
234 cannot be set below the default determined when the kernel
237 set kern.vm.kmem.size=<value> VM_KMEM_SIZE
239 Sets the size of kernel memory (bytes). This overrides
240 completely the value determined when the kernel was
243 set machdep.pccard.pcic_irq=<value>
245 Overrides the IRQ normally assigned to a PCCARD controller.
246 Typically the first available interrupt will be allocated,
247 which may conflict with other hardware. If this value is
248 set to 0, an interrupt will not be assigned and the
249 controller will operate in polled mode only.
251 set net.inet.tcp.tcbhashsize=<value> TCBHASHSIZE
253 Overrides the compile-time set value of TCBHASHSIZE or
254 the preset default of 512. Must be a power of 2.
256 set hw.physmem=<value> MAXMEM (i386 only)
258 Limits the amount of physical memory space available to
259 the system to <value> bytes. <value> may have a k, M or G
260 suffix to indicate kilobytes, megabytes and gigabytes
261 respectively. Note that the current i386 architecture
262 limits this value to 4GB.
264 On systems where memory cannot be accurately probed,
265 this option provides a hint as to the actual size of
266 system memory (which will be tested before use).
268 ################################################################################
269 # Tshow DShow the values of variables
273 Displays the value of <variable>, or all variables if not specified.
274 Multiple paths can be separated with a semicolon.
276 ################################################################################
277 # Tinclude DRead commands from a script file
279 include <filename> [<filename> ...]
281 The entire contents of <filename> are read into memory before executing
282 commands, so it is safe to source a file from removable media.
284 ################################################################################
285 # Tread DRead input from the terminal
287 read [-t <value>] [-p <prompt>] [<variable name>]
289 The read command reads a line of input from the terminal. If the
290 -t argument is specified, it will return nothing if no input has been
291 received after <value> seconds. (Any keypress will cancel the
294 If -p is specified, <prompt> is printed before reading input. No
295 newline is emitted after the prompt.
297 If a variable name is supplied, the variable is set to the value read,
298 less any terminating newline.
300 ################################################################################
301 # Tunload DRemove all modules from memory
305 This command removes any kernel and all loaded modules from memory.
307 ################################################################################
308 # Tunset DUnset a variable
310 unset <variable name>
312 If allowed, the named variable's value is discarded and the variable
315 ################################################################################