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    1 			 The Syslinux Project
    2 
    3 		   A suite of bootloaders for Linux
    4 
    5 	 Copyright 1994-2011 H. Peter Anvin and contributors
    6 
    7 This program is provided under the terms of the GNU General Public
    8 License, version 2 or, at your option, any later version.  There is no
    9 warranty, neither expressed nor implied, to the function of this
   10 program.  Please see the included file COPYING for details.
   11 
   12 ----------------------------------------------------------------------
   13 
   14       Syslinux now has a home page at http://syslinux.zytor.com/
   15 
   16 ----------------------------------------------------------------------
   17 
   18 The Syslinux suite contains the following boot loaders
   19 ("derivatives"), for their respective boot media:
   20 
   21 	SYSLINUX - MS-DOS/Windows FAT filesystem
   22 	PXELINUX - PXE network booting
   23 	ISOLINUX - ISO9660 CD-ROM
   24 	EXTLINUX - Linux ext2/ext3 filesystem
   25 
   26 For historical reasons, some of the sections in this document applies
   27 to the FAT loader (SYSLINUX) only; see pxelinux.txt, isolinux.txt and
   28 extlinux.txt for what differs in these versions.  The all-caps term
   29 "SYSLINUX" generally refers to the FAT loader, whereas "Syslinux"
   30 refers to the project as a whole.
   31 
   32 Help with cleaning up the docs would be greatly appreciated.
   33 
   34 
   35    ++++ Options ++++
   36 
   37 These are the options common to all versions of Syslinux:
   38 
   39 	-s	Safe, slow, stupid; uses simpler code that boots better
   40 	-f	Force installing
   41 	-r	Raid mode.  If boot fails, tell the BIOS to boot the next
   42 		device in the boot sequence (usually the next hard disk)
   43 		instead of stopping with an error message.
   44 		This is useful for RAID-1 booting.
   45 
   46 These are only in the Windows version:
   47 
   48 	-m	Mbr; install a bootable MBR sector to the beginning of the
   49 		drive.
   50 	-a	Active; marks the partition used active (=bootable)
   51 
   52 
   53    ++++ CREATING A BOOTABLE LINUX FLOPPY +++
   54 
   55 In order to create a bootable Linux floppy using SYSLINUX, prepare a
   56 normal MS-DOS formatted floppy.  Copy one or more Linux kernel files to
   57 it, then execute the DOS command:
   58 
   59         syslinux [-sfrma][-d directory] a: [bootsecfile]
   60 
   61 (or whichever drive letter is appropriate; the [] meaning optional.)
   62 
   63 Use "syslinux.com" (in the dos subdirectory of the distribution) for
   64 plain DOS (MS-DOS, DR-DOS, PC-DOS, FreeDOS...) or Win9x/ME.
   65 
   66 Use "syslinux.exe" (in the win32 subdirectory of the distribution) for
   67 WinNT/2000/XP.
   68 
   69 Under Linux, execute the command:
   70 
   71 	syslinux [-sfr][-d directory][-o offset] /dev/fd0
   72 
   73 (or, again, whichever device is the correct one.)
   74 
   75 This will alter the boot sector on the disk and copy a file named
   76 LDLINUX.SYS into its root directory (or a subdirectory, if the -d
   77 option is specified.)
   78 
   79 The -s option, if given, will install a "safe, slow and stupid"
   80 version of SYSLINUX.  This version may work on some very buggy BIOSes
   81 on which SYSLINUX would otherwise fail.  If you find a machine on
   82 which the -s option is required to make it boot reliably, please send
   83 as much info about your machine as you can, and include the failure
   84 mode.
   85 
   86 The -o option is used with a disk image file and specifies the byte
   87 offset of the filesystem image in the file.
   88 
   89 For the DOS and Windows installers, the -m and -a options can be used
   90 on hard drives to write a Master Boot Record (MBR), and to mark the
   91 specific partition active.
   92 
   93 If the Shift or Alt keys are held down during boot, or the Caps or Scroll
   94 locks are set, Syslinux will display a LILO-style "boot:" prompt.  The
   95 user can then type a kernel file name followed by any kernel parameters.
   96 The Syslinux loader does not need to know about the kernel file in
   97 advance; all that is required is that it is a file located in the root
   98 directory on the disk.
   99 
  100 There are two versions of the Linux installer; one in the "mtools"
  101 directory which requires no special privilege (other than write
  102 permission to the device where you are installing) but requires the
  103 mtools program suite to be available, and one in the "linux" directory
  104 which requires root privilege.
  105 
  106 
  107    ++++ CONFIGURATION FILE ++++
  108 
  109 All options here apply to PXELINUX, ISOLINUX and EXTLINUX as well as
  110 SYSLINUX unless otherwise noted.  See the respective .txt files.
  111 
  112 All the configurable defaults in SYSLINUX can be changed by putting a
  113 file called "syslinux.cfg" in the root directory of the boot disk.
  114 
  115 Starting with version 3.35, the configuration file can also be in
  116 either the /boot/syslinux or /syslinux directories (searched in that
  117 order.)  If that is the case, then all filenames are assumed to be
  118 relative to that same directory, unless preceded with a slash or
  119 backslash.
  120 
  121 The configuration file is a text file in either UNIX or DOS format,
  122 containing one or more of the following items, each on its own line with
  123 optional leading whitespace.  Case is insensitive for keywords; upper
  124 case is used here to indicate that a word should be typed verbatim.
  125 
  126 #comment
  127 	A comment line.
  128 
  129 INCLUDE filename
  130 	Inserts the contents of another file at this point in the
  131 	configuration file. Files can currently be nested up to 16
  132 	levels deep, but it is not guaranteed that more than 8 levels
  133 	will be supported in the future.
  134 
  135 DEFAULT kernel options...
  136         Sets the default command line.  If Syslinux boots automatically,
  137         it will act just as if the entries after DEFAULT had been typed
  138         in at the "boot:" prompt.
  139 
  140 	If no configuration file is present, or no DEFAULT entry is
  141         present in the config file, an error message is displayed and
  142 	the boot: prompt is shown.
  143 
  144 UI module options...
  145 	Selects a specific user interface module (typically menu.c32
  146 	or vesamenu.c32).  The command-line interface treats this as a
  147 	directive that overrides the DEFAULT and PROMPT directives.
  148 
  149 APPEND options...
  150         Add one or more options to the kernel command line.  These are
  151         added both for automatic and manual boots.  The options are
  152         added at the very beginning of the kernel command line,
  153         usually permitting explicitly entered kernel options to override
  154         them.  This is the equivalent of the LILO "append" option.
  155 
  156 SYSAPPEND bitmask
  157 IPAPPEND bitmask
  158 
  159 	The SYSAPPEND option was introduced in Syslinux 5.10; it is an
  160 	enhancement of a previous option IPAPPEND which was only
  161 	available on PXELINUX.  bitmask is interpreted as decimal format
  162 	unless prefixed with "0x" for hexadecimal or "0" (zero) for
  163 	octal.
  164 
  165 	1: indicates that an option of the following format
  166 	should be generated and added to the kernel command line:
  167 
  168 		ip=<client-ip>:<boot-server-ip>:<gw-ip>:<netmask>
  169 
  170 	... based on the input from the DHCP/BOOTP or PXE boot server.
  171 
  172 	NOTE: The use of this option is no substitute for running a
  173 	DHCP client in the booted system.  Without regular renewals,
  174 	the lease acquired by the PXE BIOS will expire, making the
  175 	IP address available for reuse by the DHCP server.
  176 
  177 	This option is empty for non-PXELINUX.
  178 
  179 	2: indicates that an option of the following format
  180 	should be generated and added to the kernel command line:
  181 
  182 		BOOTIF=<hardware-address-of-boot-interface>
  183 
  184 	... in dash-separated hexadecimal with leading hardware type
  185 	(same as for the configuration file; see pxelinux.txt.)
  186 
  187 	This allows an initrd program to determine from which
  188 	interface the system booted.
  189 
  190 	This option is empty for non-PXELINUX.
  191 
  192 	4: indicates that an option of the following format
  193 	should be generated and added to the kernel command line:
  194 
  195 		SYSUUID=<system uuid>
  196 
  197 	... in lower case hexadecimal in the format normally used for
  198 	UUIDs (same as for the configuration file; see pxelinux.txt.)
  199 	This may not be available if no valid UUID is found on the
  200 	system.
  201 
  202 	8: indicate the CPU family and certain particularly
  203 	significant CPU feature bits:
  204 
  205 		CPU=<family><features>
  206 
  207 	The <family> is a single digit from 3 (i386) to 6 (i686 or
  208 	higher.)  The following CPU feature are currently reported;
  209 	additional flags may be added in the future:
  210 
  211 		P	Physical Address Extension (PAE)
  212 		V	Intel Virtualization Technology (VT/VMX)
  213 		T	Intel Trusted Exection Technology (TXT/SMX)
  214 		X	Execution Disable (XD/NX)
  215 		L	Long Mode (x86-64)
  216 		S	AMD SMX virtualization
  217 	
  218 	This was added in 5.10.
  219 
  220 	The following strings are derived from DMI/SMBIOS information
  221 	if available; these are all new in version 5.10:
  222 	
  223 	Bit	String		Significance
  224 	-------------------------------------------------------------
  225 	0x00010	SYSVENDOR=	System vendor name
  226 	0x00020	SYSPRODUCT=	System product name
  227 	0x00040	SYSVERSION=	System version
  228 	0x00080	SYSSERIAL=	System serial number
  229 	0x00100	SYSSKU=		System SKU
  230 	0x00200	SYSFAMILY=	System family
  231 	0x00400	MBVENDOR=	Motherboard vendor name
  232 	0x00800	MBVERSION=	Motherboard version
  233 	0x01000	MBSERIAL=	Motherboard serial number
  234 	0x02000	MBASSET=	Motherboard asset tag
  235 	0x04000 BIOSVENDOR=	BIOS vendor name
  236 	0x08000	BIOSVERSION=	BIOS version
  237 	0x10000	SYSFF=		System form factor
  238 
  239 	If these strings contain whitespace they are replaced with
  240 	underscores (_).
  241 
  242 	The system form factor value is a number defined in the SMBIOS
  243 	specification, available at http://www.dmtf.org/.  As of
  244 	version 2.7.1 of the specification, the following values are
  245 	defined:
  246 
  247 	  1	Other
  248 	  2	Unknown
  249 	  3	Desktop
  250 	  4	Low profile desktop
  251 	  5	Pizza box
  252 	  6	Mini tower
  253 	  7	Tower
  254 	  8	Portble
  255 	  9	Laptop
  256 	 10	Notebook
  257 	 11	Handheld
  258 	 12	Docking station
  259 	 13	All-in-one
  260 	 14	Subnotebook
  261 	 15	Space-saving
  262 	 16	Lunch box
  263 	 17	Main server chassis
  264 	 18	Expansion chassis
  265 	 19	Subchassis
  266 	 20	Bus expansion chassis
  267 	 21	Peripheral chassis
  268 	 22	RAID chassis
  269 	 23	Rack mount chasss
  270 	 24	Sealed-case PC
  271 	 25	Multi-system chassis
  272 	 26	Compact PCI
  273 	 27	Advanced TCI
  274 	 28	Blade
  275 	 29	Blade enclosure
  276 
  277 SENDCOOKIES bitmask			[PXELINUX only]
  278 
  279 	When downloading files over http, the SYSAPPEND strings are
  280 	prepended with _Syslinux_ and sent to the server as cookies.
  281 	The cookies are URL-encoded; whitespace is *not* replaced with
  282 	underscores.
  283 
  284 	This command limits the cookies send; 0 means no cookies.  The
  285 	default is -1, meaning send all cookies.
  286 
  287 	This option is "sticky" and is not automatically reset when
  288 	loading a new configuration file with the CONFIG command.
  289 
  290 LABEL label
  291     KERNEL image
  292     APPEND options...
  293     SYSAPPEND flag_val			[5.10+]
  294     IPAPPEND flag_val			[5.10+ or PXELINUX only]
  295 	Indicates that if "label" is entered as the kernel to boot,
  296         Syslinux should instead boot "image", and the specified APPEND
  297 	and SYSAPPEND options should be used instead of the ones
  298         specified in the global section of the file (before the first
  299         LABEL command.)  The default for "image" is the same as
  300         "label", and if no APPEND is given the default is to use the
  301         global entry (if any).
  302 
  303 	Starting with version 3.62, the number of LABEL statements is
  304 	virtually unlimited.
  305 
  306         Note that LILO uses the syntax:
  307         image = mykernel
  308           label = mylabel
  309           append = "myoptions"
  310 
  311         ... whereas Syslinux uses the syntax:
  312         label mylabel
  313           kernel mykernel
  314           append myoptions
  315 
  316 	Note: The "kernel" doesn't have to be a Linux kernel; it can
  317 	      be a boot sector (see below.)
  318 
  319 	Since version 3.32 label names are no longer mangled into DOS
  320 	format (for SYSLINUX.)
  321 
  322     The following commands are available after a LABEL statement:
  323 
  324     LINUX image			- Linux kernel image (default)
  325     BOOT image			- Bootstrap program (.bs, .bin)
  326     BSS image			- BSS image (.bss)
  327     PXE image			- PXE Network Bootstrap Program (.0)
  328     FDIMAGE image		- Floppy disk image (.img)
  329     COM32 image			- COM32 program (.c32)
  330     CONFIG image		- New configuration file
  331 	Using one of these keywords instead of KERNEL forces the
  332 	filetype, regardless of the filename.
  333 
  334 	CONFIG means restart the boot loader using a different
  335 	configuration file.  The configuration file is read, the
  336 	working directory is changed (if specified via an APPEND), then
  337 	the configuration file is parsed.
  338 
  339     APPEND -
  340         Append nothing.  APPEND with a single hyphen as argument in a
  341         LABEL section can be used to override a global APPEND.
  342 
  343     LOCALBOOT type
  344 	Attempt a different local boot method.  The special value -1
  345 	causes the boot loader to report failure to the BIOS, which, on
  346 	recent BIOSes, should mean that the next boot device in the
  347 	boot sequence should be activated.  Values other than those
  348 	documented may produce undesired results.
  349 
  350 	On PXELINUX, "type" 0 means perform a normal boot.  "type" 4
  351 	will perform a local boot with the Universal Network Driver
  352 	Interface (UNDI) driver still resident in memory.  Finally,
  353 	"type" 5 will perform a local boot with the entire PXE
  354 	stack, including the UNDI driver, still resident in memory.
  355 	All other values are undefined.  If you don't know what the
  356 	UNDI or PXE stacks are, don't worry -- you don't want them,
  357 	just specify 0.
  358 
  359 	On ISOLINUX, the "type" specifies the local drive number to
  360 	boot from; 0x00 is the primary floppy drive and 0x80 is the
  361 	primary hard drive.
  362 
  363     INITRD initrd_file
  364 	Starting with version 3.71, an initrd can be specified in a
  365 	separate statement (INITRD) instead of as part of the APPEND
  366 	statement; this functionally appends "initrd=initrd_file" to
  367 	the kernel command line.
  368 
  369 	It supports multiple filenames separated by commas.
  370 	This is mostly useful for initramfs, which can be composed of
  371 	multiple separate cpio or cpio.gz archives.
  372 	Note: all files except the last one are zero-padded to a
  373 	4K page boundary.  This should not affect initramfs.
  374 
  375 IMPLICIT flag_val
  376         If flag_val is 0, do not load a kernel image unless it has been
  377         explicitly named in a LABEL statement.  The default is 1.
  378 
  379 ALLOWOPTIONS flag_val
  380 	If flag_val is 0, the user is not allowed to specify any
  381 	arguments on the kernel command line.  The only options
  382 	recognized are those specified in an APPEND statement.  The
  383 	default is 1.
  384 
  385 TIMEOUT timeout
  386         Indicates how long to wait at the boot: prompt until booting
  387         automatically, in units of 1/10 s.  The timeout is cancelled as
  388         soon as the user types anything on the keyboard, the assumption
  389         being that the user will complete the command line already
  390         begun.  A timeout of zero will disable the timeout completely,
  391         this is also the default.
  392 
  393 TOTALTIMEOUT timeout
  394         Indicates how long to wait until booting automatically, in
  395 	units of 1/10 s.  This timeout is *not* cancelled by user
  396 	input, and can thus be used to deal with serial port glitches
  397 	or "the user walked away" type situations.  A timeout of zero
  398 	will disable the timeout completely, this is also the default.
  399 
  400 	Both TIMEOUT and TOTALTIMEOUT can be used together, for
  401 	example:
  402 
  403 		# Wait 5 seconds unless the user types something, but
  404 		# always boot after 15 minutes.
  405 		TIMEOUT 50
  406 		TOTALTIMEOUT 9000
  407 
  408 ONTIMEOUT kernel options...
  409 	Sets the command line invoked on a timeout.  Normally this is
  410 	the same thing as invoked by "DEFAULT".  If this is specified,
  411 	then "DEFAULT" is used only if the user presses <Enter> to
  412 	boot.
  413 
  414 ONERROR kernel options...
  415 	If a kernel image is not found (either due to it not existing,
  416 	or because IMPLICIT is set), run the specified command.  The
  417 	faulty command line is appended to the specified options, so
  418 	if the ONERROR directive reads as:
  419 
  420 		ONERROR xyzzy plugh
  421 
  422 	... and the command line as entered by the user is:
  423 
  424 		foo bar baz
  425 
  426 	... Syslinux will execute the following as if entered by the
  427 	user:
  428 
  429 		xyzzy plugh foo bar baz
  430 
  431 SERIAL port [baudrate [flowcontrol]]
  432 	Enables a serial port to act as the console.  "port" is a
  433 	number (0 = /dev/ttyS0 = COM1, etc.) or an I/O port address
  434 	(e.g. 0x3F8); if "baudrate" is omitted, the baud rate defaults
  435 	to 9600 bps.  The serial parameters are hardcoded to be 8
  436 	bits, no parity, 1 stop bit.
  437 
  438 	"flowcontrol" is a combination of the following bits:
  439 	0x001 - Assert DTR
  440 	0x002 - Assert RTS
  441 	0x008 - Enable interrupts
  442 	0x010 - Wait for CTS assertion
  443 	0x020 - Wait for DSR assertion
  444 	0x040 - Wait for RI assertion
  445 	0x080 - Wait for DCD assertion
  446 	0x100 - Ignore input unless CTS asserted
  447 	0x200 - Ignore input unless DSR asserted
  448 	0x400 - Ignore input unless RI asserted
  449 	0x800 - Ignore input unless DCD asserted
  450 
  451 	All other bits are reserved.
  452 
  453 	Typical values are:
  454 
  455 	    0 - No flow control (default)
  456 	0x303 - Null modem cable detect
  457 	0x013 - RTS/CTS flow control
  458 	0x813 - RTS/CTS flow control, modem input
  459 	0x023 - DTR/DSR flow control
  460 	0x083 - DTR/DCD flow control
  461 
  462 	For the SERIAL directive to be guaranteed to work properly, it
  463 	should be the first directive in the configuration file.
  464 
  465 	NOTE: "port" values from 0 to 3 means the first four serial
  466 	ports detected by the BIOS.  They may or may not correspond to
  467 	the legacy port values 0x3F8, 0x2F8, 0x3E8, 0x2E8.
  468 
  469 	Enabling interrupts (setting the 0x008 bit) may give better
  470 	responsiveness without setting the NOHALT option, but could
  471 	potentially cause problems with buggy BIOSes.
  472 
  473 	This option is "sticky" and is not automatically reset when
  474 	loading a new configuration file with the CONFIG command.
  475 
  476 NOHALT flag_val
  477 	If flag_val is 1, don't halt the processor while idle.
  478 	Halting the processor while idle significantly reduces the
  479 	power consumption, but can cause poor responsiveness to the
  480 	serial console, especially when using scripts to drive the
  481 	serial console, as opposed to human interaction.
  482 
  483 CONSOLE flag_val
  484 	If flag_val is 0, disable output to the normal video console.
  485 	If flag_val is 1, enable output to the video console (this is
  486 	the default.)
  487 
  488 	Some BIOSes try to forward this to the serial console and
  489 	sometimes make a total mess thereof, so this option lets you
  490 	disable the video console on these systems.
  491 
  492 FONT filename
  493 	Load a font in .psf format before displaying any output
  494 	(except the copyright line, which is output as ldlinux.sys
  495 	itself is loaded.)  Syslinux only loads the font onto the
  496 	video card; if the .psf file contains a Unicode table it is
  497 	ignored.  This only works on EGA and VGA cards; hopefully it
  498 	should do nothing on others.
  499 
  500 KBDMAP keymap
  501 	Install a simple keyboard map.  The keyboard remapper used is
  502 	*very* simplistic (it simply remaps the keycodes received from
  503 	the BIOS, which means that only the key combinations relevant
  504 	in the default layout -- usually U.S. English -- can be
  505 	mapped) but should at least help people with AZERTY keyboard
  506 	layout and the locations of = and , (two special characters
  507 	used heavily on the Linux kernel command line.)
  508 
  509 	The included program keytab-lilo.pl from the LILO distribution
  510 	can be used to create such keymaps.  The file keytab-lilo.txt
  511 	contains the documentation for this program.
  512 
  513 DISPLAY filename
  514 	Displays the indicated file on the screen at boot time (before
  515         the boot: prompt, if displayed).  Please see the section below
  516         on DISPLAY files.
  517 
  518         NOTE: If the file is missing, this option is simply ignored.
  519 
  520 SAY message
  521 	Prints the message on the screen.
  522 
  523 PROMPT flag_val
  524         If flag_val is 0, display the boot: prompt only if the Shift or Alt
  525         key is pressed, or Caps Lock or Scroll lock is set (this is the
  526         default).  If flag_val is 1, always display the boot: prompt.
  527 
  528 NOESCAPE flag_val
  529 	If flag_val is set to 1, ignore the Shift/Alt/Caps Lock/Scroll
  530 	Lock escapes.  Use this (together with PROMPT 0) to force the
  531 	default boot alternative.
  532 
  533 NOCOMPLETE flag_val
  534 	If flag_val is set to 1, the Tab key does not display labels
  535 	at the boot: prompt.
  536 
  537 F1 filename
  538 F2 filename
  539    ...etc...
  540 F9 filename
  541 F10 filename
  542 F11 filename
  543 F12 filename
  544         Displays the indicated file on the screen when a function key is
  545         pressed at the boot: prompt.  This can be used to implement
  546         pre-boot online help (presumably for the kernel command line
  547         options.)  Please see the section below on DISPLAY files.
  548 
  549 	When using the serial console, press <Ctrl-F><digit> to get to
  550 	the help screens, e.g. <Ctrl-F><2> to get to the F2 screen.
  551 	For F10-F12, hit <Ctrl-F><A>, <Ctrl-F>B, <Ctrl-F>C.  For
  552 	compatibility with earlier versions, F10 can also be entered as
  553 	<Ctrl-F>0.
  554 
  555 PATH path
  556 	Specify a colon-separated (':') list of directories to search
  557 	when attempting to load modules. This directive is useful for
  558 	specifying the directories containing the lib*.c32 library
  559 	files as other modules may be dependent on these files, but
  560 	may not reside in the same directory. The list of directories
  561 	is searched in order. Please see the section below on PATH
  562 	RULES.
  563 
  564 Blank lines are ignored.
  565 
  566 Note that the configuration file is not completely decoded.  Syntax
  567 different from the one described above may still work correctly in this
  568 version of Syslinux, but may break in a future one.
  569 
  570 
  571    ++++ DISPLAY FILE FORMAT ++++
  572 
  573 DISPLAY and function-key help files are text files in either DOS or UNIX
  574 format (with or without <CR>).  In addition, the following special codes
  575 are interpreted:
  576 
  577 <FF>                                    <FF> = <Ctrl-L> = ASCII 12
  578         Clear the screen, home the cursor.  Note that the screen is
  579         filled with the current display color.
  580 
  581 <SI><bg><fg>                            <SI> = <Ctrl-O> = ASCII 15
  582         Set the display colors to the specified background and
  583         foreground colors, where <bg> and <fg> are hex digits,
  584         corresponding to the standard PC display attributes:
  585 
  586         0 = black               8 = dark grey
  587         1 = dark blue           9 = bright blue
  588         2 = dark green          a = bright green
  589         3 = dark cyan           b = bright cyan
  590         4 = dark red            c = bright red
  591         5 = dark purple         d = bright purple
  592         6 = brown               e = yellow
  593         7 = light grey          f = white
  594 
  595         Picking a bright color (8-f) for the background results in the
  596         corresponding dark color (0-7), with the foreground flashing.
  597 
  598 	Colors are not visible over the serial console.
  599 
  600 <CAN>filename<newline>			<CAN> = <Ctrl-X> = ASCII 24
  601 	If a VGA display is present, enter graphics mode and display
  602 	the graphic included in the specified file.  The file format
  603 	is an ad hoc format called LSS16; the included Perl program
  604 	"ppmtolss16" can be used to produce these images.  This Perl
  605 	program also includes the file format specification.
  606 
  607 	The image is displayed in 640x480 16-color mode.  Once in
  608 	graphics mode, the display attributes (set by <SI> code
  609 	sequences) work slightly differently: the background color is
  610 	ignored, and the foreground colors are the 16 colors specified
  611 	in the image file.  For that reason, ppmtolss16 allows you to
  612 	specify that certain colors should be assigned to specific
  613 	color indicies.
  614 
  615 	Color indicies 0 and 7, in particular, should be chosen with
  616 	care: 0 is the background color, and 7 is the color used for
  617 	the text printed by Syslinux itself.
  618 
  619 <EM>					<EM> = <Ctrl-Y> = ASCII 25
  620 	If we are currently in graphics mode, return to text mode.
  621 
  622 <DLE>..<ETB>				<Ctrl-P>..<Ctrl-W> = ASCII 16-23
  623 	These codes can be used to select which modes to print a
  624 	certain part of the message file in.  Each of these control
  625 	characters select a specific set of modes (text screen,
  626 	graphics screen, serial port) for which the output is actually
  627 	displayed:
  628 
  629 	Character			Text	Graph	Serial
  630 	------------------------------------------------------
  631 	<DLE> = <Ctrl-P> = ASCII 16	No	No	No
  632 	<DC1> = <Ctrl-Q> = ASCII 17	Yes	No	No
  633 	<DC2> = <Ctrl-R> = ASCII 18	No	Yes	No
  634 	<DC3> = <Ctrl-S> = ASCII 19	Yes	Yes	No
  635 	<DC4> = <Ctrl-T> = ASCII 20	No	No	Yes
  636 	<NAK> = <Ctrl-U> = ASCII 21	Yes	No	Yes
  637 	<SYN> = <Ctrl-V> = ASCII 22	No	Yes	Yes
  638 	<ETB> = <Ctrl-W> = ASCII 23	Yes	Yes	Yes
  639 
  640 	For example:
  641 
  642 	<DC1>Text mode<DC2>Graphics mode<DC4>Serial port<ETB>
  643 
  644 	... will actually print out which mode the console is in!
  645 
  646 <SUB>                                   <SUB> = <Ctrl-Z> = ASCII 26
  647         End of file (DOS convention).
  648 
  649 <BEL>					<BEL> = <Ctrl-G> = ASCII 7
  650 	Beep the speaker.
  651 
  652 
  653    ++++ COMMAND LINE KEYSTROKES ++++
  654 
  655 The command line prompt supports the following keystrokes:
  656 
  657 <Enter>		boot specified command line
  658 <BackSpace>	erase one character
  659 <Ctrl-U>	erase the whole line
  660 <Ctrl-V>	display the current Syslinux version
  661 <Ctrl-W>	erase one word
  662 <Ctrl-X>	force text mode
  663 <Tab>		list matching labels
  664 <F1>..<F12>	help screens (if configured)
  665 <Ctrl-F><digit>	equivalent to F1..F10
  666 <Ctrl-C>	interrupt boot in progress
  667 <Esc>		interrupt boot in progress
  668 <Ctrl-N>	display network information (PXELINUX only)
  669 
  670 
  671    ++++ OTHER OPERATING SYSTEMS ++++
  672 
  673 This version of Syslinux supports chain loading of other operating
  674 systems (such as MS-DOS and its derivatives, including Windows 95/98).
  675 
  676 Chain loading requires the boot sector of the foreign operating system
  677 to be stored in a file in the root directory of the filesystem.
  678 Because neither Linux kernels, nor boot sector images have reliable
  679 magic numbers, Syslinux will look at the file extension.
  680 The following extensions are recognized (case insensitive):
  681 
  682   none or other	Linux kernel image
  683   .0		PXE bootstrap program (NBP) [PXELINUX only]
  684   .bin		"CD boot sector" [ISOLINUX only]
  685   .bs		Boot sector [SYSLINUX only]
  686   .bss		Boot sector, DOS superblock will be patched in [SYSLINUX only]
  687   .c32		COM32 image (32-bit ELF)
  688   .img		Disk image [ISOLINUX only]
  689 
  690 For filenames given on the command line, Syslinux will search for the
  691 file by adding extensions in the order listed above if the plain
  692 filename is not found.  Filenames in KERNEL statements must be fully
  693 qualified.
  694 
  695 If this is specified with one of the keywords LINUX, BOOT, BSS,
  696 FDIMAGE, COM32, or CONFIG instead of KERNEL, the filetype is
  697 considered to be the one specified regardless of the filename.
  698 
  699 
  700       ++++ BOOTING DOS (OR OTHER SIMILAR OPERATING SYSTEMS) ++++
  701 
  702 This section applies to SYSLINUX only, not to PXELINUX or ISOLINUX.
  703 See isolinux.txt for an equivalent procedure for ISOLINUX.
  704 
  705 This is the recommended procedure for creating a SYSLINUX disk that
  706 can boot either DOS or Linux.  This example assumes the drive is A: in
  707 DOS and /dev/fd0 in Linux; for other drives, substitute the
  708 appropriate drive designator.
  709 
  710    ---- Linux procedure ----
  711 
  712 1. Make a DOS bootable disk.  This can be done either by specifying
  713    the /s option when formatting the disk in DOS, or by running the
  714    DOS command SYS (this can be done under DOSEMU if DOSEMU has
  715    direct device access to the relevant drive):
  716 
  717 	format a: /s
  718    or
  719 	sys a:
  720 
  721 2. Boot Linux.  Copy the DOS boot sector from the disk into a file:
  722 
  723 	dd if=/dev/fd0 of=dos.bss bs=512 count=1
  724 
  725 3. Run SYSLINUX on the disk:
  726 
  727 	syslinux /dev/fd0
  728 
  729 4. Mount the disk and copy the DOS boot sector file to it.  The file
  730    *must* have extension .bss:
  731 
  732 	mount -t msdos /dev/fd0 /mnt
  733 	cp dos.bss /mnt
  734 
  735 5. Copy the Linux kernel image(s), initrd(s), etc to the disk, and
  736    create/edit syslinux.cfg and help files if desired:
  737 
  738 	cp vmlinux /mnt
  739 	cp initrd.gz /mnt
  740 
  741 6. Unmount the disk (if applicable.)
  742 
  743 	umount /mnt
  744 
  745    ---- DOS/Windows procedure ----
  746 
  747 To make this installation in DOS only, you need the utility copybs.com
  748 (included with Syslinux) as well as the syslinux.com installer.  If
  749 you are on an WinNT-based system (WinNT, Win2k, WinXP or later), use
  750 syslinux.exe instead.
  751 
  752 1. Make a DOS bootable disk.  This can be done either by specifying
  753    the /s option when formatting the disk in DOS, or by running the
  754    DOS command SYS:
  755 
  756 	format a: /s
  757    or
  758 	sys a:
  759 
  760 2. Copy the DOS boot sector from the disk into a file.  The file
  761    *must* have extension .bss:
  762 
  763 	copybs a: a:dos.bss
  764 
  765 3. Run SYSLINUX on the disk:
  766 
  767 	syslinux a:
  768 
  769 4. Copy the Linux kernel image(s), initrd(s), etc to the disk, and
  770    create/edit syslinux.cfg and help files if desired:
  771 
  772 	copy vmlinux a:
  773 	copy initrd.gz a:
  774 
  775 
  776    ++++ NOVICE PROTECTION ++++
  777 
  778 Syslinux will attempt to detect booting on a machine with too little
  779 memory, which means the Linux boot sequence cannot complete.  If so, a
  780 message is displayed and the boot sequence aborted.  Holding down the
  781 Ctrl key while booting disables this feature.
  782 
  783 Any file that SYSLINUX uses can be marked hidden, system or readonly
  784 if so is convenient; SYSLINUX ignores all file attributes.  The
  785 SYSLINUX installed automatically sets the readonly/hidden/system
  786 attributes on LDLINUX.SYS.
  787 
  788 
  789    ++++ NOTES ON BOOTABLE CD-ROMS ++++
  790 
  791 SYSLINUX can be used to create bootdisk images for El
  792 Torito-compatible bootable CD-ROMs.  However, it appears that many
  793 BIOSes are very buggy when it comes to booting CD-ROMs.  Some users
  794 have reported that the following steps are helpful in making a CD-ROM
  795 that is bootable on the largest possible number of machines:
  796 
  797 	a) Use the -s (safe, slow and stupid) option to SYSLINUX;
  798 	b) Put the boot image as close to the beginning of the
  799 	   ISO 9660 filesystem as possible.
  800 
  801 A CD-ROM is so much faster than a floppy that the -s option shouldn't
  802 matter from a speed perspective.
  803 
  804 Of course, you probably want to use ISOLINUX instead.  See isolinux.txt.
  805 
  806 
  807    ++++ BOOTING FROM A FAT FILESYSTEM PARTITION ON A HARD DISK ++++
  808 
  809 SYSLINUX can boot from a FAT filesystem partition on a hard disk
  810 (including FAT32).  The installation procedure is identical to the
  811 procedure for installing it on a floppy, and should work under either
  812 DOS or Linux.  To boot from a partition, SYSLINUX needs to be launched
  813 from a Master Boot Record or another boot loader, just like DOS itself
  814 would.
  815 
  816 Under DOS, you can install a standard simple MBR on the primary hard
  817 disk by running the command:
  818 
  819 	FDISK /MBR
  820 
  821 Then use the FDISK command to mark the appropriate partition active.
  822 
  823 A simple MBR, roughly on par with the one installed by DOS (but
  824 unencumbered), is included in the SYSLINUX distribution.  To install
  825 it under Linux, simply type:
  826 
  827 	cat mbr.bin > /dev/XXX
  828 
  829 ... where /dev/XXX is the device you wish to install it on.
  830 
  831 Under DOS or Win32, you can install the SYSLINUX MBR with the -m
  832 option to the SYSLINUX installer, and use the -a option to mark the
  833 current partition active:
  834 
  835 	syslinux -ma c:
  836 
  837 Note that this will also install SYSLINUX on the specified partition.
  838 
  839 
  840    ++++ HARDWARE INFORMATION +++
  841 
  842 I have started to maintain a web page of hardware with known
  843 problems.  There are, unfortunately, lots of broken hardware out
  844 there; especially early PXE stacks (for PXELINUX) have lots of
  845 problems.
  846 
  847 A list of problems, and workarounds (if known), is maintained at:
  848 
  849 	http://syslinux.zytor.com/hardware.php
  850 
  851 
  852    ++++ BOOT LOADER IDS USED ++++
  853 
  854 The Linux boot protocol supports a "boot loader ID", a single byte
  855 where the upper nybble specifies a boot loader family (3 = Syslinux)
  856 and the lower nybble is version or, in the case of Syslinux, media:
  857 
  858 	0x31 (49) = SYSLINUX
  859 	0x32 (50) = PXELINUX
  860 	0x33 (51) = ISOLINUX
  861 	0x34 (52) = EXTLINUX
  862 
  863 In recent versions of Linux, this ID is available as
  864 /proc/sys/kernel/bootloader_type.
  865 
  866 
  867    ++++ PATH RULES ++++
  868 
  869 The current working directory is *always* searched first, before PATH,
  870 when attempting to open a filename. The current working directory is
  871 not affected when specifying a file with an absolute path. For
  872 example, given the following file system layout,
  873 
  874 	 /boot/
  875 		/bin/
  876 			ls.c32
  877 			libls.c32
  878 		/foo/
  879 			libls.c32
  880 
  881 assuming that the current working directory is /boot/foo, and assuming
  882 that libls.c32 is a dependency of ls.c32, executing /boot/bin/ls.c32
  883 will cause /boot/foo/libls.c32 to be loaded, not /boot/bin/libls.c32,
  884 even if /boot/bin is specified in the PATH directive of a config file.
  885 
  886 The reason that things work this way is that typically a user will
  887 install all library files in the Syslinux installation directory, as
  888 specified with the --directory installer option. This method allows
  889 the user to omit the PATH directive from their config file and still
  890 have things work correctly.
  891 
  892 
  893    ++++ BUG REPORTS ++++
  894 
  895 I would appreciate hearing of any problems you have with Syslinux.  I
  896 would also like to hear from you if you have successfully used Syslinux,
  897 *especially* if you are using it for a distribution.
  898 
  899 If you are reporting problems, please include all possible information
  900 about your system and your BIOS; the vast majority of all problems
  901 reported turn out to be BIOS or hardware bugs, and I need as much
  902 information as possible in order to diagnose the problems.
  903 
  904 There is a mailing list for discussion among Syslinux users and for
  905 announcements of new and test versions.  To join, or to browse the
  906 archive, go to:
  907 
  908    http://www.zytor.com/mailman/listinfo/syslinux
  909 
  910 Please DO NOT send HTML messages or attachments to the mailing list
  911 (including multipart/alternative or similar.)  All such messages will
  912 be bounced.