“which”命令在标准输出上没有显示任何内容

Question

当我运行which命令时，它什么也没显示。

我运行了所有这些，但没有一个给出输出。

$ which /tool/
$ which RED*.pdf
$ which anime
$ which -a anime
$ info which    
$ which -a
$ which -a Downloads
$ which Downloads
$ which doc    
$ which media
$ which /media
$ which    

$ su -
# which
# which doc
# logout

$ which --help
Illegal option --
Usage: fusrfbinfwhich [-a] args
$ which info
/usr/bin/info
$ which help
$ which cd
$ info which
$ which -a info
/usr/bin/info
$ which -a
$ which -a list.txt

Answer 1

来自man which：

NAME
       which - locate a command

SYNOPSIS
       which [-a] filename ...

DESCRIPTION
       which returns the pathnames of the files (or links) which would be executed
       in the current environment, had its arguments been given as commands in a
       strictly POSIX-conformant shell. It does this by searching the PATH for
       executable files matching the names of the  arguments. It does not follow
       symbolic links.

我不希望which给出任何输出 - 正如man页面所说，您需要一个作为命令的文件名。

尝试运行which ls。

可能是您想知道命令在哪里- 为此您需要 whereis。

$ whereis ls
ls: /bin/ls /usr/share/man/man1/ls.1.gz

Answer 2

就我而言，myscript.sh工作正常 buy which(nor whereis) 没有返回任何输出：

$ which myscript.sh
$ 

来自which手册：

描述
which 返回将在当前环境中执行的文件（或链接）的路径名，其参数在严格符合 POSIX 的 shell 中作为命令给出。 它通过在 PATH 中搜索与参数名称匹配的可执行文件来实现此目的。它不会规范化路径名。

我修复了它，将~(波形符) 更改为$HOMEon $PATH：

$ which myscript.sh
$ 

现在还whereis -l显示我添加的文件夹。

有关和 之间的区别的更多信息，请参阅此答案。~$HOME