#!/bin/bash
# logevents.sh, by Stephane Chazelas.

# ÆÄÀÏ·Î À̺¥Æ® ·Î±ëÇϱâ.
# /var/log ¿¡ ¾µ ±ÇÇÑÀÌ ÇÊ¿äÇϹǷΠ·çÆ®·Î ½ÇÇà½ÃÄÑ¾ß µË´Ï´Ù.

ROOT_UID=0     # $UID 0 ÀÎ »ç¿ëÀÚ¸¸ÀÌ ·çÆ® ±ÇÇÑÀ» °®½À´Ï´Ù.
E_NOTROOT=67   # ·çÆ®°¡ ¾Æ´Ñ »ç¿ëÀÚÀÏ °æ¿ìÀÇ Á¾·á ¿¡·¯.


if [ "$UID" -ne "$ROOT_UID" ]
then
  echo "·çÆ®·Î ½ÇÇà½ÃÄÑ¾ß µË´Ï´Ù."
  exit $E_NOTROOT
fi  


FD_DEBUG1=3
FD_DEBUG2=4
FD_DEBUG3=5

# ÀÌ ½ºÅ©¸³Æ®°¡ µ¿ÀÛÇϵµ·Ï ÇÏ·Á¸é ´ÙÀ½ µÎ ÁÙÁß¿¡ ÇÑ ÁÙÀÇ ÁÖ¼®À» Ç®±â ¹Ù¶ø´Ï´Ù.
# LOG_EVENTS=1
# LOG_VARS=1


log()  # ½Ã°£°ú ³¯Â¥¸¦ ·Î±× ÆÄÀÏ·Î ¾²±â.
{
echo "$(date)  $*" >&7     # ³¯Â¥¸¦ ÆÄÀÏ·Î *append" ½Ãŵ´Ï´Ù.
                              # ¾Æ·¡¸¦ ÂüÁ¶.
}



case $LOG_LEVEL in
 1) exec 3>&2         4> /dev/null 5> /dev/null;;
 2) exec 3>&2         4>&2         5> /dev/null;;
 3) exec 3>&2         4>&2         5>&2;;
 *) exec 3> /dev/null 4> /dev/null 5> /dev/null;;
esac

FD_LOGVARS=6
if [[ $LOG_VARS ]]
then exec 6>> /var/log/vars.log
else exec 6> /dev/null               # Ãâ·Â ¼û±â±â.
fi

FD_LOGEVENTS=7
if [[ $LOG_EVENTS ]]
then
  # then exec 7 >(exec gawk '{print strftime(), $0}' >> /var/log/event.log)
  # À­ ÁÙÀº Bash ¹öÀü 2.04 ¿¡¼­´Â µ¿ÀÛÇÏÁö ¾Ê½À´Ï´Ù.
  exec 7>> /var/log/event.log        # "event.log" ·Î append.
  log                                      # ½Ã°£°ú ³¯Â¥ ¾²±â.
else exec 7> /dev/null                  # Ãâ·Â ¼û±â±â.
fi

echo "DEBUG3: beginning" >&${FD_DEBUG3}

ls -l >&5 2>&4                       # command1 >&5 2>&4

echo "Done"                                # command2 

echo "sending mail" >&${FD_LOGEVENTS}   # "sending mail" À» 7¹ø ÆÄÀÏ µð½ºÅ©¸³ÅÍ·Î ¾²±â.


exit 0