|author||Gene Cumm <email@example.com>||2013-06-12 23:56:49 -0400|
|committer||Gene Cumm <firstname.lastname@example.org>||2013-06-12 23:56:49 -0400|
DEFAULT often references a LABEL; TIMEOUT action affected by UI. IPAPPEND/SYSAPPEND: wrap SYSAPPEND; notes on mask values 2,1. TIMEOUT-related clarifications SERIAL is sticky PATH updated for 5.10-next with notes Signed-off-by: Gene Cumm <email@example.com>
1 files changed, 39 insertions, 26 deletions
diff --git a/txt/syslinux.cfg.txt b/txt/syslinux.cfg.txt
index 3fc671fb..ff5d5337 100644
@@ -57,9 +57,10 @@ file. Files can currently be nested up to 16 levels deep, but it is not
guaranteed that more than 8 levels will be supported in the future.
*DEFAULT* 'kernel' 'options...'::
-Sets the default command line. If *Syslinux* boots automatically, it
-will act just as if the entries after *DEFAULT* had been typed in at the
-'boot:' prompt. Multiple uses will result in an override.
+Sets the default command line (which often references a LABEL). If
+*Syslinux* boots automatically, it will act just as if the entries after
+*DEFAULT* had been typed in at the 'boot:' prompt. Multiple uses will
+result in an override.
If no configuration file is present, or no *DEFAULT* or *UI* entry is
present in the config file, an error message is displayed and the
@@ -69,8 +70,9 @@ present in the config file, an error message is displayed and the
Selects a specific user interface 'module' (typically menu.c32 or
vesamenu.c32). The command-line interface treats this as a directive
that overrides the *DEFAULT* directive to load this module instead at
-startup and for an empty command line and *PROMPT* directive to not
-prompt. Multiple uses will result in an override.
+startup, for an empty command line and at timeout and *PROMPT* directive
+to not prompt (but these directives may have effects on other
+configuration parsers). Multiple uses will result in an override.
Begin a new *LABEL* clause. If 'mylabel' is entered as the kernel to
@@ -131,7 +133,7 @@ enhancement of a previous option *IPAPPEND* which was only available on
*1*::: An option of the following format should be generated, based on
the input from the DHCP/BOOTP or PXE boot server and added to the kernel
-command line(see note below):
+command line(see note below; empty for non-PXELINUX variants):
@@ -147,7 +149,7 @@ server.
dash-separated hexadecimal with leading hardware type (same as for the
configuration file; see pxelinux.txt.) and added to the kernel command
line, allowing an initrd program to determine from which interface the
+system booted(empty for non-PXELINUX variants):
@@ -162,14 +164,16 @@ line:
-*8*::: (5.10+) indicate the CPU family and certain particularly significant CPU
+*8*::: (5.10+) indicate the CPU family and certain particularly
+significant CPU feature bits:
-The <family> is a single digit from 3 (i386) to 6 (i686 or higher.) The following CPU feature are currently reported; additional flags may be added in the future:
+The <family> is a single digit from 3 (i386) to 6 (i686 or higher.) The
+following CPU features are currently reported; additional flags may be
+added in the future:
P Physical Address Extension (PAE)
@@ -180,7 +184,8 @@ L Long Mode (x86-64)
S AMD SMX virtualization
-*DMI*::: (5.10+) The following strings are derived from DMI/SMBIOS information if available:
+*DMI*::: (5.10+) The following strings are derived from DMI/SMBIOS
+information if available:
Bit String Significance
@@ -198,9 +203,12 @@ S AMD SMX virtualization
0x08000 BIOSVERSION= BIOS version
0x10000 SYSFF= System form factor
-If these strings contain whitespace they are replaced with underscores (_).
+If these strings contain white-space characters, they are replaced with
-The system form factor value is a number defined in the SMBIOS specification, available at http://www.dmtf.org/. As of version 2.7.1 of the specification, the following values are defined:
+The system form factor value is a number defined in the SMBIOS
+specification, available at http://www.dmtf.org/. As of version 2.7.1
+of the specification, the following values are defined:
@@ -323,15 +331,16 @@ explicitly named in a *LABEL* statement. The default is 1.
Indicates how long to wait at the 'boot:' prompt until booting
automatically, in units of 1/10 s. The timeout is cancelled as soon as
the user types anything on the keyboard, the assumption being that the
-user will complete the command line already begun. A timeout of zero
-(the default) will disable the timeout completely.
+user will complete the command line already begun. The timer is reset
+to 0 upon return from an unsuccessful attempt to boot or from a module.
+A timeout of zero (the default) will disable the timeout completely.
Indicates how long to wait until booting automatically, in units of
1/10 s. This timeout is *not* cancelled by user input, and can thus be
used to deal with serial port glitches or "the user walked away" type
-situations. A timeout of zero will disable the timeout completely, this
-is also the default.
+situations. A timeout of zero (the default) will disable the timeout
Both *TIMEOUT* and *TOTALTIMEOUT* can be used together, for example:
@@ -344,9 +353,8 @@ TOTALTIMEOUT 9000
// FIXME: be consistent
*ONTIMEOUT* 'kernel options...'::
-Sets the command line invoked on a timeout. Normally this is the same
-thing as invoked by 'DEFAULT'. If this is specified, then 'DEFAULT' is
-used only if the user presses <Enter> to boot.
+Sets the command line invoked on a timeout (which often references a
+LABEL). If not specified, 'UI' (if used) or 'DEFAULT is used.
*ONERROR* 'kernel options...'::
If a kernel image is not found (either due to it not existing, or
@@ -415,6 +423,9 @@ values 0x3F8, 0x2F8, 0x3E8, 0x2E8.
Enabling interrupts (setting the 0x008 bit) may give better
responsiveness without setting the *NOHALT* option, but could
potentially cause problems with buggy BIOSes.
+This option is "sticky" and is not automatically reset when loading a
+new configuration file with the CONFIG command.
If 'flag_val' is 1, don't halt the processor while idle. Halting the
@@ -498,20 +509,22 @@ screens, e.g. <Ctrl-F><2> to get to the F2 screen. For F10-F12, hit
versions, F10 can also be entered as <Ctrl-F>0.
-(5.00+) Specify a colon-separated (':') list of directories to search when
-attempting to load modules. This directive is useful for specifying the
-directories containing the lib*.c32 library files as other modules may
-be dependent on these files, but may not reside in the same directory.
+(5.00+) Specify a space-separated (' '; 5.00-5.10 was a colon ':') list
+of directories to search when attempting to load modules. This directive
+is useful for specifying the directories containing the lib*.c32 library
+files as other modules may be dependent on these files, but may not
+reside in the same directory. Multiple instances will append additional
(*PXELINUX* 5.10+) When downloading files over http, the SYSAPPEND
strings are prepended with _Syslinux_ and sent to the server as cookies.
The cookies are URL-encoded; whitespace is *not* replaced with
This command limits the cookies send; 0 means no cookies. The default
is -1, meaning send all cookies.
This option is "sticky" and is not automatically reset when loading a
new configuration file with the CONFIG command.