INITTAB(5) Linux System Administrator's Manual INITTAB(5)
NAME
inittab - format of the inittab file(1,n) used by simpleinit (sim-
pleinit-msb)
DESCRIPTION
The /etc/inittab file(1,n) determines the behaviour of init(8). The inittab
format described herein is the one used by simpleinit(8) in(1,8) the sim-
pleinit-msb variant.
The format of /etc/inittab for this version(1,3,5) of init is:
bootprog=program [ arguments ]
fileprefix=string(3,n) (usually directory name)
PATH=search path
INIT_PATH=search path
ttyline:termcap-entry:getty-command
finalprog=path
quietrollback=yes|no
ctrlaltdel=program
Lines beginning with the # character are treated as comments. Equals
signs after keywords are optional and the keywords themselves are case-
insensitive. Please see documentation for the getty(8) command that
you are using, since there are several of these in(1,8) the Linux community
at this time.
The fileprefix value is used as prefix for non-absolute pathnames in(1,8)
INIT_PATH and exported in(1,8) the environment variable INIT_D to pro-
grams/scripts started by init. It must end in(1,8) a '/' if(3,n) it is a direc-
tory.
The bootprog value is appended to the fileprefix value, and the result
specifies the boot program (usually a script). If bootprog is unspeci-
fied, the default boot program is /etc/rc (not appended to fileprefix).
The boot program has a special role among boot scripts. It is the first
boot script to be started by init(8) and the last boot script to be
stopped during shutdown(2,8)(8). It's role is to tell init, using
initctl(8), which services are to be started.
In addition to the above, the boot program is also invoked by
telinit(8) and in(1,8) certain cases by initctl(8). But these uses are
optional. At the very least the boot program must conform to the BOOT
SCRIPT GUIDELINES found in(1,8) initctl(8).
Note that the possibility to specify a directory as bootprog to cause
parallel execution of all contained scripts, which is supported by
util-linux's simpleinit, has been removed from simpleinit-msb because I
object to the idea of non-deterministic behaviour during the boot
phase. However, using the shell's ability to start jobs in(1,8) the back-
ground this feature should be easy to emulate from within the boot pro-
gram.
The PATH value is assigned to the PATH environment variable of child
processes (boot scripts). This allows them to call other programs with-
out using absolute paths, which makes user space testing easier and
adds a bit of robustness against changes.
The INIT_PATH value is used by simpleinit(8) itself and by initctl(8)
to find the location of scripts to run (if(3,n) an absolute path is not
given). If INIT_PATH contains relative pathnames (i.e. not starting
with '/'), those will be appended to fileprefix. The separation
between INIT_PATH and PATH allows a boot script to invoke a program of
the same name without conflict and without needing to specify absolute
paths.
The finalprog value specifies the path of a program to run after all
getty(8) instances are spawned. At bootup, it is passed the argument
'start'. At shutdown(2,8)(8), it is called again, this time(1,2,n) with the argu-
ment 'stop' (see shutdown(2,8)(8)).
The quietrollback value can be set(7,n,1 builtins) to "yes","true" or "1" to prevent
init from reporting the names of processes stopped when initctl(8) is
used with the "-r" option. If unset, or set(7,n,1 builtins) to any other value, init
will report the names of services as they are being stopped. Use this
option if(3,n) your service scripts have their own stop messages.
The ctrlaltdel program will be called when init receives a SIGINT (see
SIGNALS in(1,8) simpleinit(8)). On ix86 platforms, pressing Ctrl-Alt-Del
sends a SIGINT to init.
EXAMPLES
bootprog = rc 3
fileprefix = /sbin/init.d/
PATH = /usr/sbin:/usr/bin:/sbin:/bin
INIT_PATH = .:rc.1:rc.2:rc.3:rc.4:rc.5:rc.6
tty1:linux:/sbin/getty 9600 tty1
tty2:linux:/sbin/getty 9600 tty2
tty3:linux:/sbin/getty 9600 tty3
tty4:linux:/sbin/getty 9600 tty4
# tty5:linux:/sbin/getty 9600 tty5
# ttyS1:dumb:/sbin/getty 9600 ttyS1
# ttyS2:dumb:/sbin/getty -m -t60 2400 ttyS2
finalprog = /sbin/rc.xdm
quietrollback= yes
ctrlaltdel = /sbin/shutdown(2,8) -h -q now
FILES
/etc/inittab
SEE ALSO
init(8), simpleinit(8), telinit(8), initctl(8), shutdown(2,8)(8)
8 September 2001 INITTAB(5)