Prevent expansion of `~`

Question

I have a script which sync's a few files with a remote host. The commands that I want to issue are of the form

rsync -avz ~/.alias user@y:~/.alias

My script looks like this:

files=(~/.alias ~/.vimrc)

for file in "${files[@]}"; do
    rsync -avz "${file}" "user@server:${file}"
done

But the ~ always gets expanded and in fact I invoke the command

rsync -avz /home/user/.alias user@server:/home/user/.alias

instead of the one above. But the path to the home directory is not necessarily the same locally as it is on the server. I can use e.g. sed to replace this part, but it get's extremely tedious to do this for several servers with all different paths. Is there a way to use ~ without it getting expanded during the runtime of the script, but still rsync understands that the home directory is meant by ~?

That won't work, since it has to be expanded on the remote server. — pfnuesel, Nov 18 '14 at 10:30
It's expanded when you allocate the array. Just make a second array with the paths quoted in the array allocation and loop over indexes or something — Reinstate Monica Please, Nov 18 '14 at 10:35
Not sure if I understand. With `~` escaped, I get `rsync -avz /home/user/.alias user@server:\~/.alias` which does not work. — pfnuesel, Nov 18 '14 at 10:36
@pfnuesel What do you mean by `which does not work`? What happens? — Reinstate Monica Please, Nov 18 '14 at 10:40
The paths are not necessarily the same on the server. In the part of the scrip I left out, the path on the server might be edited. — pfnuesel, Nov 18 '14 at 10:52

score 2 · Accepted Answer · answered Nov 18 '14 at 10:39

files=(~/.alias ~/.vimrc)

The paths are already expanded at this point. If you don't want that, escape them or quote them.

files=('~/.alias' \~/.vimrc)

Of course, then you can't use them, because you prevented the shell from expanding '~':

~/.alias: No such file or directory

You can expand the tilde later in the command using eval (always try to avoid eval though!) or a simple substitution:

for file in "${files[@]}"; do
    rsync -avz "${file/#\~/$HOME/}" "user@server:${file}"
done

anubhava · Answer 2 · 2014-11-18T10:38:09.900

1

You don't need to loop, you can just do:

rsync -avz ~/.alias/* 'user@y:~/.alias/'

EDIT: You can do:

files=(.alias .vimrc)

for file in "${files[@]}"; do
    rsync -avz ~/"${file}" 'user@server:~/'"${file}"
done

edited Nov 18 '14 at 10:38

answered Nov 18 '14 at 10:30

anubhava

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This is a MWE. I have more than one file in my array. – pfnuesel Nov 18 '14 at 10:31
`~/.alias/*` will pick all the files from `~/.alias/` directory – anubhava Nov 18 '14 at 10:33
`.alias` is not a directory...; I changed the array in my question to make that more clear. – pfnuesel Nov 18 '14 at 10:34

Prevent expansion of `~`

2 Answers2