Re: 1.4 release schedule [Was Re: Allowing user data in lt_dlhandles (revisited)]

[Ossama Othman]

Hi Gary,

On Tue, Jan 09, 2001 at 01:13:18AM +0000, Gary V. Vaughan wrote:
> How is this interaction handled with libc functions?  Would you just
> assume that errno is useless in multi-threaded applications?  Or is

No.  See below.

> the programmer responsible for mutex locking before any call that
> might set errno, and then copying the contents of errno before
> unlocking?  Is atomicity a goal in itself?  Or is there more to being
> MT safe?

Setting errno is supposed to be thread-safe when the _REENTRANT
preprocessor macro is defined.  For example, here's what is in glibc's
`bits/errno.h' which is included by `errno.h':


#  if !defined _LIBC || defined _LIBC_REENTRANT
/* When using threads, errno is a per-thread value.  */
#   define errno (*__errno_location ())
#  endif


HTH,
-Ossama
-- 
Ossama Othman <address@hidden>
Distributed Object Computing Laboratory, Univ. of California at Irvine
1024D/F7A394A8 - 84ED AA0B 1203 99E4 1068  70E6 5EB7 5E71 F7A3 94A8