The“$#”variable stores the number of input arguments passed to a script. If the script expects at least one input argument, we can check if the“$#”variable is greater than zero. Here is an example code to check if at least one input argument exists using the“$#”variable: #!/bi...
The statementTEMP=`getopt hs $*`is used to get the input arguments when the script is invoked (such as the -h for help and -s for silent mode). The statements[ -z "$X" ]andecho "The environment variable X is not set."andusageare used to test if the string is null (-z) and ...
That tells the script to use Bash. A simple script enables you to input arguments that are passed to the script and then used for output. The first section of the script prints out the total number of arguments to pass to the scripts and then prints out the value of each argument. That...
/bin/bashif[ $# -ne2];thenecho"Please input exact two number arguments."exit1fiif[ $1-eq $2];thenecho"Number $1 and $2 are equal."elif[ $1-gt $2];thenecho"The greater is $1."elseecho"The greater is $2."fi 编写一个脚本,接收一个用户名作为参数,并判断其奇偶性。 [root@c7-...
The main difference with xtrace is that the verbose mode will only display the shell input lines as they are read. You will not see the arguments passed to the commands which is usually helpful when trying to debug a bash script. You may find useful to use both....
1. 2. 2、获取该脚本所在目录绝对路径 DIR="$( cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)" echo $DIR 1. 2. 另一种写法: readonly SCRIPT_DIR=$(dirname "$(readlink -f "${BASH_SOURCE}")") echo $SCRIPT_DIR 1. 2.
[root@c7-server ~]# bash test.sh Pleas input a user name:alongdidi User alongdidi doesn't exists. 1. 2. 3. 4. 5. 6. 7. 多分支if语句 if TEST1; then CMD1elif TEST2; then CMD2elif TEST3; then CMD3 ...else CMD-LASTfi ...
$1, $2...$nThe bash script arguments. $$The process id of the current shell. $#The total number of arguments passed to the script. $@The value of all the arguments passed to the script. $?The exit status of the last executed command. ...
echo "This script needs at least $MINPARAMS command-line arguments!" fi echo exit 0 算数运算符 $vim test.sh #!/bin/bash a=10 b=20 val=`expr $a + $b` echo "a + b : $val" val=`expr $a \* $b` echo "a * b : $val" ...
3. Create a Directory Using Command Line Arguments As an alternative to reading input interactively, most Linux commands support arguments. You can supply an argument when you run a program, to control its behavior. Within your script, you can use $1 to refer to a special variable that conta...