Re: [boost] Problem with libs/system/src/error_code.cpp

From: Oliver.Kowalke_at_[hidden]
Date: 2006-12-18 04:42:07

From: Martin Bonner

> I don't think Autoconfig /does/ help.

I'm using autoconfig in order to check if some OS features are
available.
Autoconfigure gives you the os name, version and relase.
It is a great help for multiplatform development!
For instance I test with autoconfigure if a given platform supports
MSG_NOSIGNAL flag in the
system call sendmsg.

What ??? said (I have 
> forgotten their name, and you didn't attribute the quote), is 
> that people build on Solaris 10 (which has strerror_r) and 
> then expect to be able to run on Solaris 2 (which doesn't).

On HP/UX for instance the patch level of the system is also important.
So only on teyting for os version/relase is not sufficient. 

> It seems to me that the only possible solution to that, is a 
> define which forces the use of strerror.  We don't want to 
> use strerror unless we have to (because of thread safety), 
> and the person building the code is the only person who can 
> know whether they need the capability to deploy on Solaris 2.

With aoutconfig the build process can check if strerror_r is avaliable
and provide strerror as fall back.

> Hmm.  Maybe boost should use strerror_r always, and then tell 
> people how to write their own version if the OS doesn't 
> provide it.  (Grab a lock, call strerror, copy result to 
> passed in buffer, release lock - absolutely safe against 
> multithreaded calls to strerror_r, and there's a good chance 
> that other calls to strerror will work)

Bad idea.

Oliver