Linux命令优先级 —— alias、function、内部命令(make)

MuYusen 于 2020-01-12 发布 本文总阅读量

Linux 命令优先级 —— alias、function、内部命令(make)

make

# Makefile内容
all:
@echo "Make Command echo : Hello "

$ which make
/usr/bin/make

$ make
Make Command echo : Hello

function make

#!/bin/bash

function make(){
    echo "Function Make echo : Hello"
    make

    exit
}


$ make
Function Make echo : Hello
Function Make echo : Hello

……

此时可以看到，死循环了，在function make 里面调用的还是function make

alias make

$ cat ~/bin/makex
#!/bin/bash

echo "Alias Make echo : Hello"


$ make
Alias Make echo : Hello

说明：alias make 的优先级高于command make

#!/bin/bash

echo "Alias Make echo : Hello"
make

$ make
Alias Make echo : Hello
Make Command echo : Hello

alias make 中可以直接调用内部命令make

$ cat ~/bin/makex

#!/bin/bash

function make(){
    echo "Function Makex echo : Hello"
    command make
}

echo "Alias Make echo : Hello"
make


$ make
Alias Make echo : Hello
Function Makex echo : Hello
Make Command echo : Hello

优先级：alias > function make > 内部命令make

function make 和 command make

$ cat envsetup.sh
#!/bin/bash

function make(){
    echo "Function Make echo : Hello"
    command make
}


$ make
Function Make echo : Hello
Make Command echo : Hello

结果： 1、fucntion make 的优先级高于command make 2、在function 中可以调用内部make命令，但是要加上command