[jboss-dev] Symlinks and JBoss AS ./bin/*.sh scripts

[Emmanuel Bernard]

On 29 nov. 2010, at 16:59, David M. Lloyd wrote:

> On 11/29/2010 08:04 AM, Emmanuel Bernard wrote:
>> 
>> On 28 nov. 2010, at 23:03, David M. Lloyd wrote:
>> 
>>> On 11/28/2010 10:18 AM, Emmanuel Bernard wrote:
>>>> Hey guys,
>>>> Over the week-end I've packaged JBoss AS 6 into HomeBrew (a Mac OS X packaging system made of git and ruby).
>>>> I've discovered that our scripts are not symlinks friendly and will fail (often not finding the jars).
>>>> 
>>>> I've fixed the issue but I wanted to get a review of my work. Let me know if you thing there could be a problem, otherwise I'll apply them to SVN.
>>>> [...]
>>>>   ls=`ls -ld "$PRG"`
>>>>   link=`expr "$ls" : '.*->   \(.*\)$'`
>>> 
>>> This is fragile I think.  It'd probably be better to use "readlink"
>>> instead, whose actual purpose is to read links.
>> 
>> I've tried your approach but I had a couple of issues. The main one is that readlink -f (recursive) is not standard across all platforms. The second issue I had was that readlink sometimes return links to the script basedir, sometimes as absolute. I imagine I could circumvent issue 2 (I've something for issue 1) but the fix will likely end up as weak as the original proposal (that comes from mvn, tomcat and co, so I imagine is decently battle tested).
>> 
>> Is that worth the work?
> 
> I guess it depends on how sure you are that "ls" will always output the link target after a "->".  I guess we could always try it and see if anyone complains.

The good news is that /man/ explicitly talk about '->' :)

If the file is a symbolic link, the pathname of the linked-to file is preceded by ``->''.