另一种向Bash传递命名参数的方法…是通过引用传递的。Bash 4.0支持这一点

#!/bin/bash
function myBackupFunction(){ # directory options destination filename
local directory="$1" options="$2" destination="$3" filename="$4";
  echo "tar cz ${!options} ${!directory} | ssh root@backupserver \"cat > /mnt/${!destination}/${!filename}.tgz\"";
}

declare -A backup=([directory]=".." [options]="..." [destination]="backups" [filename]="backup" );

myBackupFunction backup[directory] backup[options] backup[destination] backup[filename];

Bash 4.3的另一种语法是使用nameref。

尽管nameref无缝地取消了引用，因此更加方便，但一些较旧的受支持发行版仍然发布了较旧的版本，因此我暂时不推荐使用它。

一个简单的例子，将在执行脚本或调用函数时在脚本内部清除。

#!/bin/bash
echo "parameterized function example"
function print_param_value(){
    value1="${1}" # $1 represent first argument
    value2="${2}" # $2 represent second argument
    echo "param 1 is  ${value1}" # As string
    echo "param 2 is ${value2}"
    sum=$(($value1+$value2)) # Process them as number
    echo "The sum of two value is ${sum}"
}
print_param_value "6" "4" # Space-separated value
# You can also pass parameters during executing the script
print_param_value "$1" "$2" # Parameter $1 and $2 during execution

# Suppose our script name is "param_example".
# Call it like this:
#
# ./param_example 5 5
#
# Now the parameters will be $1=5 and $2=5

去掉括号和逗号:

 myBackupFunction ".." "..." "xx"

函数应该是这样的:

function myBackupFunction() {
    # Here $1 is the first parameter, $2 the second, etc.
}

声明函数有两种典型的方法。我更喜欢第二种方法。

function function_name {
   command...
} 

or

function_name () {
   command...
} 

调用带参数的函数:

function_name "$arg1" "$arg2"

该函数根据参数的位置(而不是名称)引用传递的参数，即$1，$2，依此类推。$0是脚本本身的名称。

例子:

function_name () {
   echo "Parameter #1 is $1"
}

此外，还需要在函数声明之后调用它。

#!/usr/bin/env sh

foo 1  # this will fail because foo has not been declared yet.

foo() {
    echo "Parameter #1 is $1"
}

foo 2 # this will work.

输出:

./myScript.sh: line 2: foo: command not found
Parameter #1 is 2

参考:高级bash脚本编写指南。

另一种向Bash传递命名参数的方法…是通过引用传递的。Bash 4.0支持这一点

#!/bin/bash
function myBackupFunction(){ # directory options destination filename
local directory="$1" options="$2" destination="$3" filename="$4";
  echo "tar cz ${!options} ${!directory} | ssh root@backupserver \"cat > /mnt/${!destination}/${!filename}.tgz\"";
}

declare -A backup=([directory]=".." [options]="..." [destination]="backups" [filename]="backup" );

myBackupFunction backup[directory] backup[options] backup[destination] backup[filename];

Bash 4.3的另一种语法是使用nameref。

尽管nameref无缝地取消了引用，因此更加方便，但一些较旧的受支持发行版仍然发布了较旧的版本，因此我暂时不推荐使用它。

它从用户那里获取两个数字，将它们提供给名为add的函数(在代码的最后一行)，add将对它们求和并输出。

#!/bin/bash

read -p "Enter the first  value: " x
read -p "Enter the second value: " y

add(){
    arg1=$1 # arg1 gets to be the first  assigned argument (note there are no spaces)
      arg2=$2 # arg2 gets to be the second assigned argument (note there are no spaces)

    echo $(($arg1 + $arg2))
}

add x y # Feeding the arguments