Re: Improved implementation of *env(3) functions in "libc"

[Steven Bellovin <smb%cs.columbia.edu@localhost>]

On Nov 18, 2010, at 10:47 37AM, Andrew Doran wrote:

> My concern with using a tree is that it makes a concurrent getenv() very
> hard to implement, and threaded programs like to make use of getenv().
> 
> Reader-writer locks don't scale on multi-core systems, and applications
> like this one (getenv) may give you single threaded or worse behaviour.
> 
> 
I don't think this is a serious issue for getenv().  Most applications make
very little use of it; when they do, it's generally at initialization time.
Nor, I suspect, is single-threading a huge concern, since the lock will be
held for a very short time.


                --Steve Bellovin, http://www.cs.columbia.edu/~smb