1. #!/bin/bash
  2.  
  3. mylogger() {
  4.  
  5.   local log_file="$1"
  6.   local lock_file="$log_file.lock"
  7.   local LOG_FD
  8.   local line
  9.   local logbuffer=()
  10.   local counter=0
  11.   local buffer_size=1000 
  12.  
  13.   trap "mylog_flush $log_file $lock_file" EXIT INT HUP TERM
  14.  
  15.   while IFS= read -r line ; do
  16.     logbuffer+=("$line")
  17.     ((counter++))
  18.  
  19.     if [ $counter -ge $buffer_size ] ; then
  20.       mylog_flush "$log_file" "$lock_file"
  21.     fi
  22.  
  23.   done
  24.   mylog_flush "$log_file" "$lock_file"
  25. }
  26.  
  27. mylog_flush() {
  28.  
  29.  local log_file="$1"
  30.  local lock_file="$2"
  31.  
  32.  [ -z "$counter" ] && return
  33.  
  34.  # $logfile bei Bedarf oeffnen
  35.  [ -n "$LOG_FD" ] || exec {LOG_FD}<>$lock_file
  36.  
  37.  dbg "logbuffer flush, logbuffer_count: ${#logbuffer} counter: ${counter}"  
  38.  local i
  39.  if flock --exclusive --timeout 10 $LOG_FD ;then
  40.          for((i=0;i<$counter;i++));do
  41.                  dbg "writing line >${logbuffer[$i]}< ..." 
  42.                  echo "${logbuffer[$i]}" >>$log_file
  43.          done
  44.          logbuffer=()
  45.          counter=0
  46.          rm -f $lock_file
  47.          flock --unlock $LOG_FD
  48.  fi
  49. }
  50.  
  51. dbg() {
  52.         # Debug ausgabe am Bildschirm
  53.         if [ "$DEBUG" == "1" ] ;then
  54.                 echo "DEBUG: $*" >&2
  55.         fi
  56. }
  57.  
  58. machwas() {
  59.         local i=0
  60.         for((x=1;x<=10;x++)) ; do
  61.                 for name in anton peter "" susanne fritz mira markus tina ;do
  62.                         echo "$name"
  63.                 done
  64.         done
  65.  
  66.         }
  67.  
  68. # --- Hauptprogramm ---
  69.  
  70. declare -x DEBUG=1
  71.  
  72. # - mehrere logger definieren -
  73. #
  74. logger_data()  { mylogger data.log  ; }
  75. logger_extra() { mylogger extra.log ; }
  76.  
  77. machwas | logger_data
  78. machwas | logger_extra