echo "numberTwelve variable is greater than 12" else echo "neither of the statemens matched" fi 输出如下: [zexcon@fedora ~]$ ./learnToScript.sh numberTwelve variable is equal to 12 你所看到的是if语句的第一行,它在检查变量的值是否真的等于12。如果是的话,语句就会停止,并发出numberTwelve is...
echo -e $variable 这样,将会按照换行符进行换行输出变量的值。 对于Bash/Shell脚本中插入换行符的应用场景,可以用于生成具有多行文本格式要求的配置文件、日志文件、邮件内容等。在这些场景下,使用换行符可以使文本更加清晰易读。 腾讯云相关产品和产品介绍链接地址: 腾讯云服务器(CVM):https://cloud.tencent.com/pro...
if[[ -e file_a ]];thenecho file_a exists elif[[ -e file_b ]];thenecho file_b existselseecho none exists fi 这里-e的意思是假如文件存在则为真,否则为假。其他的判断条件有 -v varname True if the shell variable varname is set (has been assigned a value). -z string True if the ...
...hadoop102:/A/a , 执行脚本后,将此文件同步到集群中所有机器的 /A/a 用户在使用xsync时,只需要传入要同步的文件即可 xysnc a 不管a是一个相对路径还是绝对路径,都需要将.../bin/bash #校验参数是否合法 if(($#==0)) then echo 请输入要分发的文件!...bin目录,如果没有就新建一个bin目录,因为...
So if you want to know the PID of the current shell, all you have to do is use the$$variable in the terminal: echo $$ $-: Find the set of options used in the current shell You can set various options to tweak how the bash should behave and using the$-variable, you can print ...
statement to check whether the string is empty. For this, we have used the “-z” option within the square brackets condition of the “if” part of the statement and stated the variable “V” with the “$” sign in inverted commas. If the condition is satisfied and the string is found...
${string/pattern/replacement} It matches the pattern in the variable $string, and replace only the first match of the pattern with the replacement. $catfirstmatch.sh#! /bin/bash filename="bash.string.txt"echo"After Replacement:"${filename/str*./operations.} ...
Bash provides basic operations for manipulating strings. To create a string variable in Bash, you simply assign a value to a variable name ? mystring="Hello, world!" To display contents of string variable, you can use echo command ?
echo $result The output will be Fedora,Ubuntu,CentOS. Looking at the output, a loop is used to combine (concatenate) the items in the “items” array into a single string and then separated by comma. How to Concatenate Strings in Bash with the += Operator One more method to concatenate...
string integer expression file testexits with the status determined by EXPRESSION. Placing the EXPRESSION between square brackets ([and]) is the same as testing the EXPRESSION withtest. To see the exit status at the command prompt, echo the value “$?” A value of 0 means th...