Write your own Linux server part two

David M Williams
Monday, 20 August 2007 21:18

Business IT - Open Source

# -----------------------------------------------------------------------------
# Configurable options ...
# Comment out any of the following lines to use dwserv's default values.
# -----------------------------------------------------------------------------

DWSERV_DIR=.

# Edit the following to change the port number that dwserv
# runs at. Any client program must specify this port number to connect.
PORT=4000

# Edit the following to increase or decrease the connection queue. This
# probably need not be touched unless dwserv is expected to
# receive many simultaneous connections.
QLEN=5

# Turn on or off logging - use 'on' or 'off'
LOG=on

# Edit the following to specify where the logfile is to be stored - this
# will only take effect if logging is switched on (above).
LOGFILE=/tmp/dwsvr.log

# Edit the following to specify if verbose logging should be performed.
# This will create a larger log file but will give much more information
# about what is happening - use 'yes' or 'no'
VERBOSE=yes

# -----------------------------------------------------------------------------
# Nothing below here needs modification
# -----------------------------------------------------------------------------

getPID_Linux ()
{
 PID=`ps -e | grep dwserv | grep -v grep | cut -c1-5`
}

getPID_SunOS ()
{
 PID=`ps -ejf | grep dwserv | grep -v grep | cut -c10-14`
}

getPID=getPID_`uname`
$getPID

case "$1" in
 stop)
  if [ "a$PID" = "a" ];
  then
   echo "dwserv is not running"
   exit 1
  fi

  kill -9 $PID > /dev/null 2>&1
  sleep 1

  $getPID
  if [ "a$PID" = "a" ];
  then
   echo "dwserv stopped"
  else
   echo "dwserv could not be stopped"
  fi
  ;;

 start)
  if [ "a$PID" != "a" ];
  then
   echo "dwserv is already running"
   exit 1
  fi

  COMMANDLINE=

  if [ "a$PORT" != "a" ];
  then
   COMMANDLINE="$COMMANDLINE -p$PORT"
  fi

  if [ "a$QLEN" != "a" ];
  then
   COMMANDLINE="$COMMANDLINE -q$QLEN"
  fi

  if [ "$LOG" = "on" ];
  then
   COMMANDLINE="$COMMANDLINE -l"

   if [ "$VERBOSE" = "yes" ];
   then
    COMMANDLINE="$COMMANDLINE -v"
   fi

   if [ "a$LOGFILE" != "a" ];
   then
    COMMANDLINE="$COMMANDLINE -f$LOGFILE"
   fi
  fi

  $DWSERV_DIR/dwserv $COMMANDLINE > /dev/null 2>&1

  $getPID
  if [ "a$PID" = "a" ];
  then
   echo "dwserv could not be started"
  else
   echo "dwserv running"
  fi
  ;;

 *)
  echo "Usage: dwserv {start|stop}"
  if [ "a$PID" != "a" ];
  then
   echo "dwserv is running"
  else
   echo "dwserv is not running"
  fi
  exit 1
esac