lfs-book-zh_CN/bootscripts/lfs/init.d/rc

#!/bin/sh
########################################################################
# Begin rc
#
# Description : Main Run Level Control Script
#
# Authors     : Gerard Beekmans  - gerard@linuxfromscratch.org
# Update      : Bruce Dubbs - bdubbs@linuxfromscratch.org
#
# Version     : LFS 7.0
#
########################################################################

. /lib/boot/functions

print_error_msg()
{
   echo_failure
   # $i is set when called
   boot_mesg -n "FAILURE:\n\nYou should not be reading this error message.\n\n" ${FAILURE}
   boot_mesg -n " It means that an unforeseen error took"
   boot_mesg -n " place in ${i}, which exited with a return value of"
   boot_mesg " ${error_value}.\n"
   boot_mesg_flush
   boot_mesg -n "If you're able to track this"
   boot_mesg -n " error down to a bug in one of the files provided by"
   boot_mesg -n " the LFS book, please be so kind to inform us at"
   boot_mesg " lfs-dev@linuxfromscratch.org.\n"
   boot_mesg_flush
   boot_mesg -n "Press Enter to continue..." ${INFO}
   boot_mesg "" ${NORMAL}
   wait_for_user
}

check_script_status()
{
   # $i is set when called
   if [ ! -f ${i} ]; then
      boot_mesg "${i} is not a valid symlink." ${WARNING}
      echo_warning
      continue
   fi

   if [ ! -x ${i} ]; then
      boot_mesg "${i} is not executable, skipping." ${WARNING}
      echo_warning
      continue
   fi
}

# This sets a few default terminal options.
stty sane

# These 3 signals will not cause our script to exit
trap "" INT QUIT TSTP

[ "${1}" != "" ] && runlevel=${1}

if [ "${runlevel}" = "" ]; then
   echo "Usage: ${0} <runlevel>" >&2
   exit 1
fi

previous=${PREVLEVEL}
[ "${previous}" = "" ] && previous=N

if [ ! -d /etc/rc.d/rc${runlevel}.d ]; then
   boot_mesg "/etc/rc.d/rc${runlevel}.d does not exist." 
   exit 1
fi

# Attempt to stop all services started by the previous runlevel,
# and killed in this runlevel
if [ "${previous}" != "N" ]; then
   for i in $(ls -v /etc/rc.d/rc${runlevel}.d/K* 2> /dev/null)
   do
      check_script_status

      suffix=${i#/etc/rc.d/rc$runlevel.d/K[0-9][0-9]}
      prev_start=/etc/rc.d/rc$previous.d/S[0-9][0-9]$suffix
      sysinit_start=/etc/rc.d/rcsysinit.d/S[0-9][0-9]$suffix

      if [ "${runlevel}" != "0" ] && [ "${runlevel}" != "6" ]; then
         if [ ! -f ${prev_start} ] && [ ! -f ${sysinit_start} ]; then
            boot_mesg -n "WARNING:\n\n${i} can't be" ${WARNING}
            boot_mesg -n " executed because it was not"
            boot_mesg -n " not started in the previous"
            boot_mesg -n " runlevel (${previous})."
            boot_mesg "" ${NORMAL}
            boot_mesg_flush
            continue
         fi
      fi
      ${i} stop
      error_value=${?}

      if [ "${error_value}" != "0" ]; then
         print_error_msg
      fi
   done
fi

[ "${previous}" = "N" ] && IN_BOOT=1

#Start all functions in this runlevel
for i in $( ls -v /etc/rc.d/rc${runlevel}.d/S* 2> /dev/null)
do
   if [ "${previous}" != "N" ]; then
      suffix=${i#/etc/rc.d/rc$runlevel.d/S[0-9][0-9]}
      stop=/etc/rc.d/rc$runlevel.d/K[0-9][0-9]$suffix
      prev_start=/etc/rc.d/rc$previous.d/S[0-9][0-9]$suffix

      [ -f ${prev_start} ] && [ ! -f ${stop} ] && continue
   fi

   check_script_status

   case ${runlevel} in
      0|6)
         ${i} stop
         ;;
      *)
         ${i} start
         ;;
   esac
   error_value=${?}

   if [ "${error_value}" != "0" ]; then
      print_error_msg
   fi
done

# End rc