a=14b=24result=expr `$a + $b` 上面这种代码执行时就会报错:bash:command not found
1. Perform string matching operations expr command helps us to perform different levels of string matching operations with the operator ‘:’ as shown below, # partial match and returns the number of characters matched. $ expr linux : lin 3 # the condition is string 2 entirely should match i...
One Linux Command Per Day (4) expr e x p r命令一般用于整数值,但也可用于字符串。一般格式为: expr argument operator argument e x p r也是一个手工命令行计数器。 参数使用规则: 用空格隔开每个项; 用\ (反斜杠) 放在 shell 特定的字符前面; 对包含空格和其他特殊字符的字符串要用引号括起来 deyuy...
https://www.computerhope.com/unix/uexpr.htm https://www.runoob.com/linux/linux-comm-expr.html https://www.geeksforgeeks.org/expr-command-in-linux-with-examples/ 1. 2. 3.
...WindrunnerMax/EveryDay 参考 https://www.computerhope.com/unix/uexpr.htm https://www.runoob.com/linux/linux-comm-expr.html...https://www.geeksforgeeks.org/expr-command-in-linux-with-examples/ 55820 七、expr命令 1.语法和功能 只能用于整数运算和字符串长度、匹配等运算处理 expr 2 + 2 ...
computerhope.com/unix/uexpr.htm https://www.runoob.com/linux/linux-comm-expr.html https://www.geeksforgeeks.org/expr-command-in-linux-with-examples/ 本文参与 腾讯云自媒体同步曝光计划,分享自作者个人站点/博客。 原始发表:2021-01-25 ,如有侵权请联系 cloudcommunity@tencent.com 删除 前往查看...
每日一题https://github.com/WindrunnerMax/EveryDay 参考https://www.computerhope.com/unix/uexpr.htm https://www.runoob.com/linux/linux-comm-expr.html https://www.geeksforgeeks.org/expr-command-in-linux-with-examples/
(2)until语法:until command do list done (3)for语法:for name in word1 word2…wordN do list done 例:输出1~10。 #!/bin/sh x=1 for x in 1 2 3 4 5 6 7 8 9 10 do echo $x done (4)select语法:select name in word1 word2…wordN ...
[command [argume> true exit [n] type [-afptP] name [name ...] export [-fn] [name[=value] ...] or ex> typeset [-aAfFilrtux] [-p] name[=val> false ulimit [-SHacdefilmnpqrstuvx] [limit> fc [-e ename] [-lnr] [first] [last] o> umask [-p] [-S] [mode] fg [job...
command(1) comp_err(1) compare(1) composite(1) compress(1) config.guess(1) config.sub(1) config_data(1) conflict(1) conjure(1) constype(1) continue(1) convert(1) convmv(1) corelist(1) cp(1) cp(1g) cpack(1) cpan(1) cpan2dist(1) cpanp(1) cpio(1) cpp(1) cpp(1) cpu...