Unix Shell Notes

$$当前进程的pid$!子进程的pid##start.sh##MYPIDFILE=my.pidnohupshscript.sh&echo$!>$MYPIDFILEnohupshscript2.sh&echo$!>>$MYPIDFILE##stop.sh##MYPIDFILE=my.pidcd$MYSRCwhilereadppid;do   foriin`ps-ef|awk’$3==’${ppid}'{print$2}’`   do       echokillingpid$i       kill-9$i   done   echokillingppid$ppid   kill-9$ppiddone<$MYPIDFILErm-f$MYPIDFILEREF:http://www.unix.com/shell-programming-scripting/44170-pid-nohup-process.html另外,在某个时间段内   MYHOUR=`date’+%H’`   if[$MYHOUR-gt17-a$MYHOUR-lt21];then   …   fi