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标题: About let command.... [打印本页]

作者: dozec 时间: 2007-01-31 16:53
标题: About let command....
[nie@hellokitty ~]$ let $((count=1))
[nie@hellokitty ~]$ echo $?
0
[nie@hellokitty ~]$ let $((count=0))
[nie@hellokitty ~]$ echo $?
1

who can explain it?
Thanks.

作者: 寂寞烈火 时间: 2007-01-31 17:02
http://bbs.chinaunix.net/viewthr ... p;extra=&page=7

作者: 一梦如是 时间: 2007-01-31 17:20

   let arg [arg ...]
            Each arg is an arithmetic expression to be evaluated (see ARITH-
            METIC  EVALUATION).  If the last arg evaluates to 0, let returns
            1; 0 is returned otherwise.

$((count=0))会被shell变量替换成什么，可以echo出来看

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