Shell运算
Shell運算
abc????abc.txt????anaconda-ks.cfg????cal.txt????Desktop????find.sh????install.log????install.log.syslog
[root@oracle11g ~]# echo * ?//只顯示文件, 不包含目錄
abc abc.txt anaconda-ks.cfg cal.txt Desktop find.sh install.log install.log.syslog
[root@oracle11g ~]# echo $[ 2+8 ]
10
[root@oracle11g ~]# echo $[2+8]
10
[root@oracle11g ~]# echo $[ 2>>8 ] //將2向右移8位,左邊補0
0
[root@oracle11g ~]# echo $[ 2<<4 ] ?//將2向左移4位,右邊補0
32
[root@oracle11g ~]# echo $[ 2^4 ] ?//異或運算
6
[root@oracle11g ~]# echo $[ 2 | 4 ] //或運算
6
[root@oracle11g ~]# echo $[ ~3 ] ?//取反,將所有的二進制位1->0, 0->1
-4[simpleanti@PLATQA136025?logs]$?var=100? [simpleanti@PLATQA136025?logs]$?let?var=$var+4? [simpleanti@PLATQA136025?logs]$?echo?$var? 104? [simpleanti@PLATQA136025?logs]$?let?var+=5? [simpleanti@PLATQA136025?logs]$?echo?$var? 109?
9
1、運算
使用雙引號可以引用除字符$、·、\外的任何字符和字符串
[root@oracle11g ~]# lsabc????abc.txt????anaconda-ks.cfg????cal.txt????Desktop????find.sh????install.log????install.log.syslog
[root@oracle11g ~]# echo * ?//只顯示文件, 不包含目錄
abc abc.txt anaconda-ks.cfg cal.txt Desktop find.sh install.log install.log.syslog
[root@oracle11g ~]# echo $[ 2+8 ]
10
[root@oracle11g ~]# echo $[2+8]
10
[root@oracle11g ~]# echo $[ 2>>8 ] //將2向右移8位,左邊補0
0
[root@oracle11g ~]# echo $[ 2<<4 ] ?//將2向左移4位,右邊補0
32
[root@oracle11g ~]# echo $[ 2^4 ] ?//異或運算
6
[root@oracle11g ~]# echo $[ 2 | 4 ] //或運算
6
[root@oracle11g ~]# echo $[ ~3 ] ?//取反,將所有的二進制位1->0, 0->1
-4
2、賦值運算
=、+=、-=、*=、、=、%=、&=、^=、!=、<<=、>>= let count=$count+$change let?count+=$change3、表達式替換
[root@oracle11g ~]# echo $[ 10#8 + 1 ] ? //8進制的10,在加上1, 即99
轉(zhuǎn)載于:https://blog.51cto.com/tianya23/269777
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