svn commit: r199827 - in head: include lib/libc/compat-43 sys/sys

[M. Warner Losh]

In message: <20091202132904.GH2368 at deviant.kiev.zoral.com.ua>
            Kostik Belousov <kostikbel at gmail.com> writes:
: On Wed, Dec 02, 2009 at 07:25:56PM +1000, Dima Panov wrote:
: > On Thursday 26 November 2009 23:49:38 Konstantin Belousov wrote:
: > > Author: kib
: > > Date: Thu Nov 26 13:49:37 2009
: > > New Revision: 199827
: > > URL: http://svn.freebsd.org/changeset/base/199827
: > > 
: > > Log:
: > >   Implement sighold, sigignore, sigpause, sigrelse, sigset functions
: > >   from SUSv4 XSI. Note that the functions are obsoleted, and only
: > >   provided to ease porting from System V-like systems. Since sigpause
: > >   already exists in compat with different interface, XSI sigpause is
: > >   named xsi_sigpause.
: > > 
: > >   Reviewed by:	davidxu
: > >   MFC after:	3 weeks
: > > 
: > > Modified:
: > >   head/include/signal.h
: > >   head/lib/libc/compat-43/Makefile.inc
: > >   head/lib/libc/compat-43/Symbol.map
: > >   head/lib/libc/compat-43/sigcompat.c
: > >   head/lib/libc/compat-43/sigpause.2
: > >   head/sys/sys/signal.h
: > >   head/sys/sys/signalvar.h
: > 
: > kib, you forgot about osversion bump, it is strongly needed.
: No. My interpretation of __FreeBSD_version is that the bump indicates
: incompatible change in the interfaces. Sometime it is used to mark the
: point where big changes hit the tree, possibly not related to interface
: change.
: 
: Also, __FreeBSD_version denotes the kernel "version". We do support
: running earlier usermode on the later kernels. Think about kernel-only
: upgrades, compatXx libs and jails which can run arbitrary earlier
: usermode. (The change in question is purely libc).
: 
: Said this, I think it is actually harmful practice to bump
: __FreeBSD_version after API additions or feature implementation.
: 
: I can bump version for this case, but due to the above reason,
: it would not make much sense.

In the past, __FreeBSD_version has been used to expose changes in
interfaces (both plus, minus and delta) that are necessary for the
entire system.  Adding an interface definitely qualifies because this
is a build-time issue, not a run time one.

Unfortunately, __FreeBSD_version has also been used to force kernel
recompiles lately since it is encoded in the kernel modules.  Despite
this, it isn't just for kernels...

Warner

: > This changeset caused jdk (may be not only jdk) breakage, as jdk-bsd-patches
: > always provide own implementations of sigingnore() for FreeBSD.
: > 
: > Patch for jdk16 port will be ready soon.
: 
: Ok, thanks for working on this.