linux shell »ù±¾ÃüÁî

1.²»Ìáʾɾ³ýĿ¼  rm -rf ${dir}
2.rpm ²é¿´²¢Ð¶ÔØÈí¼þ
  rpm -qa | grep ${appname}
  rpm -e ${rpmname}
3.Êýѧ¼ÆËãÖ®bc
  echo "3 + 4 - 5 * 5 - 7 " | bc
 echo "3 + 4 - 5 * 5 - 7 " | bc | read myresult
4.²é¿´½ø³Ì
  ps -ef £ü grep ${tname}
exp: ps -ef | grep java
        ps -ef | grep mysql
5.Æô¶¯/Í£Ö¹·þÎñ
 service ${servername} start
service ${servername} stop
6.ÈÕÖ¾¼à¿Ø
  tail -f  $applog
7.Îļþ²éÕÒ
  grep "${searchcxt}" ${file}
8.Îļþ½ØÈ¡,ÄÚÈÝÌæ»»,ÄÚÈÝÌáÈ¡
 Ìæ»» sed 's/abc/cde/g' $file
 Ìæ»»abcΪcde
 sed -n '1,20p' $file > $newfile 1-20ÐÐÊä³öµ½ÐÅÎļþ
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