在Linxu环境下执行一条命令,看似相同,实际上命令是分为不同类型:
下面是一个例子:
~> type pwd pwd is a shell builtin ~> type cd cd is a shell builtin ~> type echo echo is a shell builtin ~> type python3 python3 is /usr/bin/python3 ~> type cat cat is hashed (/usr/bin/cat) ~> type ls ls is aliased to `ls --color=auto' ~> type tensorboard -bash: type: tensorboard: not found
解释:
pwd
,cd
和echo
都是bash的内置命令;python3
是普通的外部命令;cat
是hashed外部命令;ls
是一个别名命令,其真实命令是ls --color=auto