帮忙 解释一下这段脚本的含义

帮忙 解释一下这段脚本的含义

#!/bin/sh
EXCUTE_NAME="racer"
X_NAME="race"
verify_system()
{
  #check if this is a linux platform, if not linux, alert and quit
  if [ `uname` != "Linux" ]; then
echo "This process being available ONLY on Linux"
   return 1
  fi
  #check if it's root, otherwise quit
  if [ `whoami` != "root" ]; then
   echo "No more than root has previlege to run this process"
   return 1
  fi
  #check size of log file
  if [ -f "ecou.log" ]; then
FSIZE=`du -ks ecou.log | awk '{print $1}'`
if [ $FSIZE -gt 1000 ]; then
  >ecou.log #clear the log file
fi
  else
             >ecou.log
  fi
  
  return 0
}
find_ecou()
{
   #FINDNUM=`ps -ef | grep "$EXCUTE_NAME" | grep -v grep | wc -l`
   FINDNUM=`pgrep -nx "$EXCUTE_NAME" | wc -l`
   if [ $FINDNUM -eq 0 ]; then
return 1
   else
return 0
   fi
}
start_ecou()
{
  if find_ecou
  then
echo "The pocess is running"
exit
  fi
  #to which interface link with Internet
  INTERNUM=`ifconfig -a | grep "HWaddr" | wc -l`
  if [ $INTERNUM -eq 0 ]; then
echo "No net Interface can be found, may you type command such as insmod and ifup eth0 first"
return 1
  fi
  #if more than ONE eth installed, have to select one
  CMPNUM=0
  if [ "$INTERNUM" -gt "$CMPNUM" ]; then
ifconfig -a | grep "HWaddr" | awk '
   BEGIN {
  i=0;
  printf("All names of your net interface installed\n");
  printf("-----------------------------------------\n");
   }
   {
  printf("\t%s\t%d\n", $1, i);
  i++;
   }'
         echo -n "Input one name to hace access with Internet (eth0): "
  read INTERNAME
  if [ ! $INTERNAME ]; then   #default name is eth0
  INTERNAME="eth0"
  fi
  #if the name input is correct or not
  TMP_NUM=`ifconfig -a | grep "HWaddr" | grep "$INTERNAME" | wc -l`
  if [ $TMP_NUM -eq 0 ]; then
  echo "You have input an invalid name of net interface"
  return 1
  fi
  else
INTERNAME=`ifconfig -a |grep "HWaddr" | awk '{print $1}'`
  fi
  echo "The name of interface is: " $INTERNAME
  #okey, we have got correct env & parameters to run this process
  #However, definitly necessary ini files as well as process file must be found
  #in the same path
  if [ ! -f "racer.ini" ]; then
echo "Warning: No relative file racer.ini found, re-creating"
echo "Server1=218.29.0.227" >racer.ini
echo "Server2=218.29.0.228" >>racer.ini
  fi
  if [ ! -f "$X_NAME" ]; then
echo "Unable to find process to run, try re-install your process again!"
return 1
  fi
   
  if [ ! -x "$X_NAME" ]; then
chmod +x $X_NAME
  fi
  
  if [ ! -L "$EXCUTE_NAME" ]; then
ln -s $X_NAME $EXCUTE_NAME
  fi
  
  ./$EXCUTE_NAME $INTERNAME
  RETVAL=$?
  if [ ! $RETVAL -eq 0 ]; then
echo "Failed to run the process"
  else
echo "$EXCUTE_NAME has been started successfully"
  fi
  
  return 0
}
#for help info
usage()
{
echo "Usage: $0 {[start]|[status]|[stop]}"
}
#to stop ecou
stop_ecou()
{
    #ps -ef | grep "$EXCUTE_NAME" | grep -v grep | awk '{print $2}' | xargs kill -SIGINT 2>/dev/null
    pgrep -nx "$EXCUTE_NAME" | xargs kill -SIGINT 2>/dev/null
    FINDNUM=1
    while [ ! $FINDNUM -eq 0 ]
    do
     #FINDNUM=`ps -ef | grep "$EXCUTE_NAME" | grep -v grep | wc -l`
     FINDNUM=`pgrep -nx "$EXCUTE_NAME" | wc -l`
     sleep 1
    done
    if [ $? -eq 0 ]; then
        echo "The process has been halted successfully"
    else
        echo "Failed to terminate the process OR the process is not running"
    fi
}
#to tell status
tell_status()
{
   #ps -ef | grep "$EXCUTE_NAME" | grep -v grep | awk '{print $2}' | xargs kill  -SIGUSR1 2>/dev/null
   pgrep -nx "$EXCUTE_NAME" | xargs kill  -SIGUSR1 2>/dev/null
   if [ $? -eq 0 ]; then
return;
   else
echo "No status returned for $EXCUTE_NAME"
   fi
}
#main
  PARAM_NUM=$#
  if [ ! $PARAM_NUM -eq 1 ]; then
    usage
    exit
  fi
  
  if [ -n $RACERC ]; then
      cd $RACERC
  fi
  if ! verify_system
  then
     exit
  fi
  case $1 in
start)  start_ecou;;
        status) tell_status;;
        stop)  stop_ecou;;
*) usage;;
  esac      
看来是一个网络版的赛车游戏,脚本是先检查是否为Linux平台(不是则退出),然后测试网卡,然后就应该是联网进行游戏了,注释已经写得清楚了,哪里还用解释脚本的含义?