A non-quoted backslash ‘\’ is the Bash escape character. It preserves the literal value of the next character that follows, with the exception ofnewline. If a\newlinepair appears, and the backslash itself is not quoted, the\newlineis treated as a line continuation (that is, it is rem...
type命令本身也是内置命令。 $ type typetype is a shell builtin 如果要查看一个命令的所有定义,可以使用type命令的-a参数。 $ type -a echoecho is shell builtinecho is /usr/bin/echoecho is /bin/echo 上面代码表示,echo命令即是内置命令,也有对应的外部程序。 type命令的-t参数,可以返回一个命令的类...
${parameter/pattern/string} 参考${parameter//pattern/string} ${parameter//pattern/string} ${parameter//pattern/string}和${parameter/pattern/string},主要实现了字符串替换,当然,如果要替换的结果是空,就等效于删除。一个/,表示只有第一个匹配的被替换,两个/表示所有匹配的都替换。例如: Copy $ str="we...
复制 $ printf"String with backslash: %b\n""Hello\nWorld!"String with backslash: Hello World! 1. 2. 3. 当使用%c时,它一次只读取一个字符: 复制 $ printf"Character: %c\n"a Character: a$ printf"Character: %c\n"a b c Character: a Character: b Character: c$ printf"Character: %c\n...
You can assign data to a variable using the equals sign (=). The data you store in a variable can either be a string or a number. Let’s create a variable now on the command line: chapter_number=5 The variable name is on the left hand side of the equals sign, and the data whic...
# remove the last character in string and return it in $rval if [ -z "$1" ]; then # empty string rval="" return fi # wc puts some space behind the output this is why we need sed: numofchar=`echo -n "$1" | wc -c | sed 's/ //g' ` ...
In this example we declare simple bash variable and print it on the screen ( stdout ) with echo command. #!/bin/bash STRING="HELLO WORLD!!!" echo $STRING 1. 2. 3. Your backup script and variables: #!/bin/bash OF=myhome_directory_$(date +%Y%m%d).tar.gz ...
string) ， 把 $expect_out(buffer) 或者 $expect_out(NUMBER, string) 的结果通过set 赋值给变量，...
Curl请求是一种用于发送HTTP请求的命令行工具,常用于与Web服务器进行通信。在Bash中,如果需要转义无法识别的字符,可以使用反斜杠(\)进行转义。 具体步骤如下: 1. 打开终端或命令行界面...
Linux - Get first character of a string SHELL, The $ is interpreted by the shell before your program/script is even started. If you don't want to interpret it, you have to escape it somehow. – paxdiablo. Jan 6, 2015 at 3 The guy just asked how to get first char of string, Rem...