Comboot/menu.c32

Additional items that must be documented (in both doc/menu.txt and this page) since 4.0:

• New MENU IMMEDIATE --- permit hotkeys to activate immediately without needing Enter.
• New MENU HELP statement to display fullscreen help text as a result of a menu selection. documented
• New MENU HIDDENKEY command to provide a one-keystroke way to activate a boot option from a hidden menu intro screen. documented
• New MENU SAVE statement. documented
• New MENU CLEAR statement. documented
• New MENU SHIFTKEY statement. documented
• New MENU RESOLUTION statement. documented

(See also Syslinux 4 Changelog and How do I configure Syslinux )

( Note that since version 3.74, the default directive usage has changed. Use UI instead) ( See UI mode or Changes in 3.74 )

Note: Some minor updated documentation can be seen at the Menu wiki page.
The content of doc/menu.txt (6.04-pre1, with some updates):

There are two menu systems included with Syslinux, the advanced menu system, and the simple menu system.

THE ADVANCED MENU SYSTEM

The advanced menu system, written by Murali Krishnan Ganapathy, is located in the com32/cmenu/ sub-directory. It allows the user to create hierarchical sub-menus, dynamic options, check-boxes, and just about anything. It requires the menu to be compiled from a simple C file (see com32/cmenu/simple.c and com32/cmenu/complex.c for examples).

The advanced menu system does not support serial console at this time.

See com32/cmenu/README for more information.

THE SIMPLE MENU SYSTEM

The simple menu system is based on a module located at com32/menu/vesamenu.c32 (graphical) or com32/menu/menu.c32 (text mode only). It uses the same configuration file as the regular Syslinux command line, and displays all the LABEL statements.

To use the menu system, simply make sure [vesa]menu.c32 is in the appropriate location for the boot medium (the same directory as the configuration file for SYSLINUX, EXTLINUX and ISOLINUX, and the same directory as pxelinux.0 for PXELINUX), and put the following options in the configuration file:

UI menu.c32

There are a few menu additions to the configuration file, all starting with the keywords MENU or TEXT. As the rest of the Syslinux configuration file language, it is case-insensitive.

The remainder of this document is a reference of the directives that are relevant in the Simple Menu System.

MENU TITLE title

Give the menu a title. The title is presented at the top of the menu.

MENU HIDDEN

Do not display the actual menu unless the user presses a key. All that is displayed is a timeout message.

MENU HIDDENKEY key[,key...] command...

If the key used to interrupt MENU HIDDEN is "key", then execute the specified command instead of displaying the menu.

Currently, the following key names are recognized:

Backspace, Tab, Enter, Esc, Space, F1..F12, Up, Down, Left, Right, PgUp, PgDn, Home, End, Insert, Delete

... in addition to all single characters plus the syntax " ^X " for " [Ctrl-X] ". Note that single characters are treated as case sensitive, so "A" and "a" can bind different commands. The same command can be bound to different keys by giving a comma-separated list of them:

menu hiddenkey A,a key_a_command

MENU CLEAR

Clear the screen when exiting the menu, instead of leaving the menu displayed. For vesamenu, this means the graphical background is still displayed without the menu itself for as long as the screen remains in graphics mode.

MENU SHIFTKEY

Exit the menu system immediately unless either the Shift or the Alt key is pressed, or Caps Lock or Scroll Lock is set.

MENU SEPARATOR

Insert an empty line in the menu.

MENU LABEL label

(Only valid after a LABEL statement.)

Change the label displayed for a specific menu entry. Display a label that is not suitable for the command line. For example:

 # Soft Cap Linux
 LABEL softcap
  MENU LABEL Soft Cap ^Linux 9.6.36
  KERNEL softcap-9.6.36.bzi
  APPEND whatever
  
 # A very dense operating system
 LABEL brick
  MENU LABEL ^Windows CE/ME/NT
  KERNEL chain.c32
  APPEND hd0 2

The caret symbol (^) in a MENU LABEL statement defines a hotkey. Hotkeys are highlighted in the menu. When a hotkey is pressed, the cursor will move to the corresponding menu entry. If MENU IMMEDIATE is present, then when a hotkey is pressed the corresponding menu entry will be immediately launched.

Reusing hotkeys has no effect on subsequent entries; they will not be highlighted, and the cursor will not move to them when the hotkey is pressed again.

Keep in mind that the LABELs, not MENU LABELs, must be unique, or odd things will happen to the command-line.

MENU INDENT count

(Only valid after a LABEL statement.)

Add "count" spaces in front of the displayed menu entry.

MENU DISABLE

(Only valid after a LABEL statement.)

Make the entry unselectable. This allows to display a section in the menu with different options below it. For example:

# Entries for network boots
LABEL -
  MENU LABEL Network:
  MENU DISABLE
 
# Soft Cap Linux
LABEL softcap
  MENU LABEL Soft Cap ^Linux 9.6.36
  MENU INDENT 1
 KERNEL softcap-9.6.36.bzi
 APPEND whatever
 
# Dos 6.22
LABEL dos
  MENU LABEL ^Dos 6.22
  MENU INDENT 1
 KERNEL memdisk
 APPEND initrd=dos622.imz
 
# Separator
  MENU SEPARATOR
 
# Entries for local boots
LABEL -
  MENU LABEL Local:
  MENU DISABLE
 
# Windows 2000
LABEL w2k
  MENU LABEL ^Windows 2000
  MENU INDENT 1
 KERNEL chain.c32
 APPEND hd0 1
 
# Windows XP
LABEL xp
  MENU LABEL Windows ^XP
  MENU INDENT 1
 KERNEL chain.c32
 APPEND hd0 2

MENU HIDE

(Only valid after a LABEL statement.)

Suppress a particular LABEL entry from the menu.

MENU DEFAULT

(Only valid after a LABEL statement.)

The particular menu entry is considered the default for the particular (sub)menu. If no default is specified, use the first one. See also the DEFAULT directive.

TEXT HELP
Help text ...
... which can span multiple lines
ENDTEXT

(Only valid after a LABEL statement.)

Specify a help text that should be displayed when a particular selection is highlighted.

MENU PASSWD passwd

(Only valid after a LABEL statement, or a MENU BEGIN statement.)

Set a password on this menu entry. "passwd" can be either a cleartext password or a password encrypted with one of the following algorithms:

MD5 (Signature: $1$) SHA-1 (Signature: $4$) SHA-2-256 (Signature: $5$) SHA-2-512 (Signature: $6$)

Use the included Perl scripts "sha1pass" or "md5pass" to encrypt passwords. MD5 passwords are compatible with most Unix password file utilities; SHA-1 passwords are probably unique to Syslinux; SHA-2 passwords are compatible with very recent Linux distributions. Obviously, if you don't encrypt your passwords they will not be very secure at all.

If using passwords, make sure to use "NOESCAPE 1" and "PROMPT 0", and either set "ALLOWOPTIONS 0" or use a master password (see below).

If passwd is an empty string, this menu entry can only be unlocked with the master password.

MENU MASTER PASSWD passwd

Set a master password. This password can be used to boot any menu entry. If this directive is used, then the master password is also required for the [Tab] and [Esc] keys to work.

MENU RESOLUTION width height

Request a specific screen resolution when in graphics mode. The default is "640 480" corresponding to a resolution of 640x480 pixels, which all VGA-compatible monitors should be able to display.

If the requested resolution is unavailable, the text mode menu is displayed instead.

MENU BACKGROUND background

For vesamenu.c32, set the background image. The background can either be a color (see MENU COLOR) or the name of an image file, which should be the size of the screen (normally 640x480 pixels, but see MENU RESOLUTION) and either in PNG, JPEG or LSS16 format.

Note: When using an image file as background, its resolution should match the values used in MENU RESOLUTION.

MENU BEGIN [tagname]
MENU END

Begin/end a submenu. The entries between MENU BEGIN and MENU END form a submenu, which is marked with a ">" mark on the right hand of the screen. Submenus inherit the properties of their parent menus, but can override them, and can thus have their own backgrounds, master passwords, titles, timeouts, messages and so forth.

MENU GOTO tagname

(Only valid after a LABEL statement.)

Transfer to the named submenu instead of booting anything. To transfer to the top-level menu, specify "menu goto .top".

MENU EXIT [tagname]

(Only valid after a label statement inside MENU BEGIN ... MENU END.)

Exit to the next higher menu, or, if tagname is specified, to the named menu.

MENU QUIT

(Only valid after a LABEL statement.)

Quit the menu system.

WARNING: Even if either MENU MASTER PASSWD or "ALLOWOPTIONS 0" is set, MENU QUIT will still allow exiting to the CLI; however, a separate MENU PASSWD can of course be set for this label / menu entry.

MENU START

(Only valid inside MENU BEGIN ... MENU END.)

Define the starting menu for the menu system, instead of starting at the top-level menu. See also the DEFAULT directive.

DEFAULT label

Set the global default. If "label" points into a submenu, that menu becomes the start menu. In other words, this directive has the same effect as both MENU DEFAULT and MENU START.

For backwards compatibility with earlier versions of Syslinux, this behavior is ignored unless the configuration file also contains a UI directive.

Note: the CLI accepts options after the label, or even a non-label. The menu system does not support that.

MENU SAVE
MENU NOSAVE

Remember the last selected entry and make that one the default for the next boot. A password-protected menu entry is *not* saved. This requires the ADV data storage mechanism, which is currently only implemented for SYSLINUX, although the other Syslinux derivatives will accept the command (and ignore it).

NOTE: MENU SAVE stores the LABEL tag of the selected entry. This mechanism therefore relies on LABEL tags being unique. On the other hand, it handles changes in the configuration file gracefully.

NOTE: In software RAID-1 setups, MENU SAVE only stores the default label on the actual boot disk. This may lead to inconsistent reads from the array, or unexpectedly change the default label after array resynchronization or disk failure.

The MENU SAVE information can be fully cleared with "extlinux --reset-adv <bootdir>".

A MENU SAVE or MENU NOSAVE at the top of a (sub)menu affects all entries underneath that (sub)menu except those that in turn have MENU SAVE or MENU NOSAVE declared. This can be used to restrict which specific entries are allowed to be saved when executed.

INCLUDE filename [tagname]
MENU INCLUDE filename [tagname]

Include the contents of the "filename" configuration file at this point.

In the case of MENU INCLUDE, the included data is only seen by the menu system; the core Syslinux code does not parse this command, so any labels defined in it are unavailable.

If a tagname is included, the whole file is considered to have been bracketed with a MENU BEGIN tagname ... MENU END pair, and will therefore show up as a submenu.

MENU AUTOBOOT message

Replace the message "Automatic boot in # second{,s}...". The "#" symbol is replaced with the number of remaining seconds. The syntax "{singular,[dual,]plural}" can be used to conjugate appropriately.

MENU TABMSG message

Replace the message "Press [Tab] to edit options".

MENU NOTABMSG message

Take the place of the TABMSG message when the [Tab] key is not allowed, i.e. if the possibility to edit the command is disabled. Defaults to blank.

MENU PASSPROMPT message

Replace the message "Password required".

MENU COLOR element ansi foreground background shadow

Set the color of element "element" to the specified color sequence:

screen Rest of the screen border Border area title Title bar unsel Unselected menu item hotkey Unselected hotkey sel Selection bar hotsel Selected hotkey disabled Disabled menu item scrollbar Scroll bar tabmsg Press [Tab] message cmdmark Command line marker cmdline Command line pwdborder Password box border pwdheader Password box header pwdentry Password box contents timeout_msg Timeout message timeout Timeout counter help Help text msgXX Message (F-key) file attribute XX

... where XX is two hexadecimal digits (the "plain text" is 07).

"ansi" is a sequence of semicolon-separated ECMA-48 Set Graphics Rendition (<ESC>[m) sequences:

0 reset all attributes to their defaults 1 set bold 4 set underscore (simulated with color on a color display) 5 set blink 7 set reverse video 22 set normal intensity 24 underline off 25 blink off 27 reverse video off 30 set black foreground 31 set red foreground 32 set green foreground 33 set brown foreground 34 set blue foreground 35 set magenta foreground 36 set cyan foreground 37 set white foreground 38 set underscore on, set default foreground color 39 set underscore off, set default foreground color 40 set black background 41 set red background 42 set green background 43 set brown background 44 set blue background 45 set magenta background 46 set cyan background 47 set white background 49 set default background color

These are used (a) in text mode, and (b) on the serial console.

"foreground" and "background" are color codes in #AARRGGBB notation, where AA RR GG BB are hexadecimal digits for alpha (opacity), red, green and blue, respectively. #00000000 represents fully transparent, and #ffffffff represents opaque white.

"shadow" controls the handling of the graphical console text shadow. Permitted values are "none" (no shadowing), "std" or "standard" (standard shadowing - foreground pixels are raised), "all" (both background and foreground raised), and "rev" or "reverse" (background pixels are raised).

If any field is set to "*" or omitted (at the end of the line) then that field is left unchanged.

The current defaults are:

menu color screen 37;40 #80ffffff #00000000 std menu color border 30;44 #40000000 #00000000 std menu color title 1;36;44 #c00090f0 #00000000 std menu color unsel 37;44 #90ffffff #00000000 std menu color hotkey 1;37;44 #ffffffff #00000000 std menu color sel 7;37;40 #e0000000 #20ff8000 all menu color hotsel 1;7;37;40 #e0400000 #20ff8000 all menu color disabled 1;30;44 #60cccccc #00000000 std menu color scrollbar 30;44 #40000000 #00000000 std menu color tabmsg 31;40 #90ffff00 #00000000 std menu color cmdmark 1;36;40 #c000ffff #00000000 std menu color cmdline 37;40 #c0ffffff #00000000 std menu color pwdborder 30;47 #80ffffff #20ffffff std menu color pwdheader 31;47 #80ff8080 #20ffffff std menu color pwdentry 30;47 #80ffffff #20ffffff std menu color timeout_msg 37;40 #80ffffff #00000000 std menu color timeout 1;37;40 #c0ffffff #00000000 std menu color help 37;40 #c0ffffff #00000000 std menu color msg07 37;40 #90ffffff #00000000 std

MENU MSGCOLOR fg_filter bg_filter shadow

Set all the msgXX colors to a color scheme derived from the fg_filter and bg_filter values. Background color zero is always treated as transparent. The default corresponds to:

menu msgcolor #90ffffff #80ffffff std

This directive should come before any directive that customizes individual msgXX colors.

MENU WIDTH 80
MENU MARGIN 10
MENU PASSWORDMARGIN 3
MENU ROWS 12
MENU TABMSGROW 18
MENU CMDLINEROW 18
MENU ENDROW -1
MENU PASSWORDROW 11
MENU TIMEOUTROW 20
MENU HELPMSGROW 22
MENU HELPMSGENDROW -1
MENU HIDDENROW -2
MENU HSHIFT 0
MENU VSHIFT 0

These options control the layout of the menu on the screen.

The values above are the defaults.

A negative value is relative to the calculated length of the screen (25 rows for text mode, 28 rows for VESA graphics mode).

F1 textfile [background]
...
F12 textfile [background]

Display full-screen help (also available at the command line). The same control code sequences as in the command line interface are supported, although some are ignored.

Additionally, an optional second argument allows a different background image to be displayed by vesamenu.c32 (see MENU BACKGROUND for supported formats). The CLI and menu.c32 will ignore the second argument.

MENU HELP textfile [background]

Create a menu entry which, when selected, displays full-screen help in the same way as the F-key help.

The menu system honours the TIMEOUT command. If TIMEOUT is specified, it will execute the ONTIMEOUT command if one exists, otherwise it will pick the DEFAULT menu option. WARNING: the TIMEOUT action will bypass password protection even if one is set for the specified ONTIMEOUT and/or DEFAULT entry!

Normally, users can press [Tab] to edit the menu entry, and [Esc] to return to the Syslinux command line. However, if the configuration file specifies "ALLOWOPTIONS 0", these keys will be disabled, and if MENU MASTER PASSWD is set, they require the master password.

The simple menu system supports serial console, using the normal SERIAL directive. However, it can be quite slow over a slow serial link; you probably want to set your baudrate to 38400 or higher if possible. It requires a Linux/VT220/ANSI-compatible terminal on the other end.

USING AN ALTERNATE CONFIGURATION FILE

It is also possible to load a secondary configuration file, to get to another menu. To do that, invoke (vesa)menu.c32 with the name of the secondary configuration file.

LABEL othermenu
 MENU LABEL Another Menu
 KERNEL menu.c32
 APPEND othermenu.conf

If you specify more than one file, they will all be read, in the order specified. The dummy filename "~" (tilde) is replaced with the filename of the main configuration file.

# The file graphics.conf contains common color and layout commands for # all menus. LABEL othermenu MENU LABEL Another Menu KERNEL vesamenu.c32 APPEND graphics.conf othermenu.conf # Return to the main menu LABEL mainmenu MENU LABEL Return to Main Menu KERNEL vesamenu.c32 APPEND graphics.conf ~

See also the MENU INCLUDE directive above.