echo输出到文件 变量值缺失

jalowang

求高手看看下面这段代码
用echo 语句输出到log文件的时候，有时候$batch变量的值会丢失
也不确定是不是fork了以后在sub process里面多执行了一次？ 网上查了点资料，不过还是找不出具体原因

while true
do
  if true
  then
     if true
     then
        #get top record in queuelist
        batch=`head -n 1 $queueFile`

        #remove batch from queue list
        batch2=$(echo "$batch"|sed 's/\//\\\//g')
        sed -i "/$batch2/d" $queueFile

        echo "run $batch at $(date +%Y%m%d%H%M%S) " >> $logFile
        $batch &
     fi
  fi
sleep 10
done

----------Log文件内容：--------------
run /apps/scripts/batch/tacs_qxmon.sh at 20130904160501
run /apps/scripts/batch/edi/batch_cron.tacs_ediprod.sh_asn at 20130904161601
run /apps/scripts/batch/tacs_bar_imp.sh at 20130904161701
run /apps/scripts/batch/tacs_bar_exp.sh at 20130904161801
run  at 20130904161951
run  at 20130904162211
run  at 20130904162251
run /apps/scripts/batch/edi/batch_cron.tacs_ediprod.sh_asn at 20130904163102
run /apps/scripts/batch/tacs_bar_imp.sh at 20130904163202
run /apps/scripts/batch/tacs_bar_exp.sh at 20130904163302
run /apps/scripts/batch/edi/batch_cron.tacs_ediprod.sh_asn at 20130904164602
run /apps/scripts/batch/tacs_bar_imp.sh at 20130904164722
run /apps/scripts/batch/tacs_bar_exp.sh at 20130904164802
run  at 20130904164922
run  at 20130904165042
run  at 20130904165152
run  at 20130904165602

seesea2517

空行吧？
______________

jason680

回复 1# jalowang

It seems no issue on echo

batch=`head -n 1 $queueFile`  #<== I think issue here, it's not echo issue

echo "run $batch at $(date +%Y%m%d%H%M%S) " >> $logFile