[Users] [ET Trac] [Einstein Toolkit] #453: Formaline deletes files if lib and src are symlinks

[Erik Schnetter]

On Tue, Jun 21, 2011 at 1:56 PM, Roland Haas
<roland.haas at physics.gatech.edu> wrote:
> Hello all,
>
>>  Yes, that is the idea. The patch as stop-gap measure, and then trying to
>>  understand the real cause of the problem and correcting git-add-thorn.pl.
>>
>>  I do not think that Mac OS allows hard links to directories for regular
>>  users. With these, one can create directory structures that are not
>> trees,
>>  which would break many Unix expectations; in particular, one can create
>>  directory structures disconnected from the root directory and hence
>>  unreachable. Root can call the "link" syscall (maybe even from the "ln"
>>  command, possibly with a special option) to do this, but it's highly
>>  discouraged.
>
> If this issue is just that Mac OS allows hard links for directories then
>  simply changing link() to symlink() for directories:
> http://perldoc.perl.org/functions/symlink.html should fix the issue,
> shouldn't it?
>
> Something like:
>
> if(-d $object) {
>  symlink(...)
> } else {
>  link(...)
> }

The overall goal of this code is to create a shadow hierarchy of the
actual thorn with all relevant files. For this, all directories are
created via mkdir, and all files are hardlinked. After calling "git
add", this shadow directory is deleted again. (This is necessary
because "git add" can't be made to follow symbolic links.)

In other words, the link command should never encounter directories.
An expression "! -type d" to a previous find should prevent this. The
error may be somewhere else -- maybe in the find command?

I never expected to have to follow symbolic links within thorns
(including within the flesh). I am not sure it is a good idea to
follow them, because symbolic links can easily be circular. I rather
think symbolic links should be placed into the git repository "as is".

-erik

-- 
Erik Schnetter <schnetter at cct.lsu.edu>   http://www.cct.lsu.edu/~eschnett/