What does it mean when a symbolic link (symlink) is red in Ubuntu?

Question

~/temp$ mkdir dir1
~/temp$ mkdir dir2
~/temp$ mkdir dir2/dir21
~/temp$ ln -s dir2/dir21 dir1/ln2dir21
~/temp$ mkdir dir1/ln2dir21/dir3
mkdir: cannot create directory ‘dir1/ln2dir21/dir3’: No such file or directory

What does the following command:

~/temp$ ln -s dir2/dir21 dir1/ln2dir21

create (there are no errors for the ln command)? The created link dir1/ln2dir21 is red and it's type is lrwxrwxrwx which seems to be a link. Then why can't create directory through that symbolic link?

Solution 1

The dir1/ln2dir21 symbolic link you created is relative to dir1.

The correct command would be:

ln -s ../dir2/dir21 dir1/ln2dir21

As another test, if you go to dir1 and create dir2/dir21 you will see that the red indicator will go away:

cd dir1
mkdir -p dir2/dir21
ll

You will see ln2dir21 -> dir2/dir21/ in normal color (no red error color).

Solution 2

~/temp$ mkdir dir1/ln2dir21/dir3 you can't create a directory in a directory that is inexistent use mkdir -p

ln -s dir2/dir21 dir1/ln2dir21 is not working, because you're a) linking to a file not a dirrectory and b) it should be a full path. https://stackoverflow.com/a/9104390

so it should be: ln -s ~/temp/dir2/dir21/ ./dir1/ln2dir21

and it should workl...

Comments

[guiverc]

Have you tried reading the manual page? ie. man ln ?

[guiverc]

Does this answer your question? Question about the symlink of the ln command

[jw_]

I'v read them, but there are too much like form 1/2/3/4 so not very carefully...

[FedKad]

dir1/ln2dir21 symbolic link is relative to dir1. The correct command would be ln -s ../dir2/dir21 dir1/ln2dir21.

[guiverc]

man ls tells me "ln [OPTION]... [-T] TARGET LINK_NAME" ie. TARGET is first so that's the target of the command, LINK_NAME is second which is the link (-s tells it symbolic) created. SPACES are delimiters, ie. "dir2/dir21" is the TARGET and "dir1/ln2dir21" the LINK_NAME in format path/file (where file can be the name of a file or a directory (file contains more files; in posix/unix/linux everything is a file in a way)

[jw_]

Failure without any error message? ln should print an error message "symbol link not created, target not exists, <absolute target path>"

[Jesse Nickles]

See also: stackoverflow.com/questions/37866313/…

[jw_]

I'm linking to a file, not directory.