xsession-daemon

   1 #!/bin/sh
   2 # Stolen from and based on Robert Cutajar
   3 # https://askubuntu.com/a/421718
   4
   5 if [ "$#" == "0" ] ;
   6 then
   7     echo "Session daemon missing command" >&2
   8     echo "USAGE: $0 command [args...]"
   9     echo "Executes given command with args only once per XDG seat (session)."
  10     echo "Keeps PID and log of the executed command."
  11     exit 1
  12 fi
  13
  14 COMMAND=$1
  15 shift
  16
  17 NAME="${COMMAND##*/}"
  18 PIDFILE=~/.cache/xsession-daemon/$NAME-$XDG_SEAT.pid
  19 LOGFILE=~/.cache/xsession-daemon/$NAME-$XDG_SEAT.log
  20 PID=""
  21 PIDDIR="${PIDFILE%/*}"
  22 LOGDIR="${LOGFILE%/*}"
  23
  24 mkdir -p $PIDDIR
  25 if [ $? -ne 0 ]; then
  26     echo "Session daemon PIDDIR not there: $PIDDIR" >&2
  27     exit 2
  28 fi
  29
  30 mkdir -p $LOGDIR
  31 if [ $? -ne 0 ]; then
  32     echo "Session daemon LOGDIR not there: $LOGDIR" >&2
  33     exit 2
  34 fi
  35
  36 if [ -e "$PIDFILE" ] ; then
  37     PID=`cat "$PIDFILE"`
  38     echo "Session daemon '$NAME' PID found: $PID"
  39
  40     if pgrep -F "$PIDFILE" "${NAME}" >/dev/null ; then
  41         echo "Session daemon '$NAME' was already running with PID $PID" >&2
  42         exit 3
  43     fi
  44 else
  45     echo "Session daemon '$NAME' PIDFILE NOT found: $PIDFILE"
  46 fi
  47
  48
  49 echo "Session daemon running $COMMAND $* > $LOGFILE 2>&1"
  50 $COMMAND $* > "$LOGFILE" 2>&1 &
  51 PID=$!
  52 ERR=$?
  53 sleep 1
  54
  55 if [ "$PID" ] && [  $ERR == 0 ] && kill -0 "$PID" 2>/dev/null; then
  56     echo -n $PID > "$PIDFILE"
  57     echo "Session daemon '$NAME' started with PID $PID"
  58 else
  59     echo "Session daemon '$NAME' did not start or finished early. PID: $PID, ERR: $ERR" >&2
  60     cat "$LOGFILE" >&2
  61     exit 4
  62 fi