How to store a path with white spaces into a varia

问题:

I want to store /c/users/me/dir name into a variable to pass it to cd system call.

Works when typing:

$ cd '/c/users/me/dir name'

or

$ cd /c/users/me/dir\ name

but does not works if I store it:

$ dirname="'/c/users/me/dir name'"
$ cd $dirname
$ bash: cd: /c/users/me/dir: No such file or directory

the same result to:

$ dirname=('/c/users/me/dir name')

or

$ dirname=(/c/users/me/dir\ name)

Which is the right way to store it?

回答1:

Double-quote your path variable with spaces, to preserve it,

dirName="/c/users/me/dir name"
cd "$dirName"

Actually, dirname is a shell built-in, recommend using an alternate name to avoid confusion with the actual command.

From the man bash page,

Enclosing characters in double quotes (‘"’) preserves the literal value of all characters within the quotes, with the exception of ‘$’, ‘`’, ‘\’, and, when history expansion is enabled, ‘!’.

回答2:

While using a bash variable you should double-quote it to preserve its state.

x='/home/ps/temp/bla bla'
 cd $x      ### <----used without double quotes. 
sh: cd: /home/ps/temp/bla: No such file or directory


 cd "$x"    ### <---While using a bash variable you should double-quote it to presever its state.
 pwd
/home/ps/temp/bla bla