Re: Question about libcdda_paranoia
Look at the debian dir of the package you are backporting. ;) Hint - k3b-0.9/debian/patches/02_k3bcdparanoialib.dpatch My fault: i did not do a backport. I just build a woody package from pure upstream sources... But thank you for the hint. Henning
Question about libcdda_paranoia
Hi! I wonder why there is a symbolic link /usr/lib/libcdda_paranoia.so - libcdda_paranoia.so.0.9.8 in package 'libcdparanoia0-dev'. Shouldn't that be in 'libcdparanoia0'? Regards Henning
Re: Question about libcdda_paranoia
On Wed, Oct 08, 2003 at 01:13:45PM +0200, Henning Moll wrote: I wonder why there is a symbolic link /usr/lib/libcdda_paranoia.so - libcdda_paranoia.so.0.9.8 in package 'libcdparanoia0-dev'. Shouldn't that be in 'libcdparanoia0'? No, plain .so links are only needed for build-time linking, and therefore live in development packages. See: http://www.debian.org/doc/debian-policy/ch-sharedlibs.html#s-sharedlibs-dev -- Colin Watson [EMAIL PROTECTED]
Re: Question about libcdda_paranoia
On Wednesday 08 October 2003 13:27, Colin Watson wrote: No, plain .so links are only needed for build-time linking, and therefore live in development packages. Thank you for that information! But now i am in a bit of trouble: i packaged a woody backport of k3b. This programm tries to dlopen (=at runtime) 'libcdda_paranoia.so'. But that is only possible if package 'libcdparanoia0-dev' is installed. This would mean a dependency to a development package. Is this a bug in k3b? Should k3b try to dlopen 'libcdda_paranoia.so.0' instead? Is there a standard for so-naming (which is respected by all/ most Gnu/Linux distributions)? Where can i learn more about the naming of share object files? Thanks in advance! Henning
Re: Question about libcdda_paranoia
On Wed, Oct 08, 2003 at 04:58:34PM +0200, Henning Moll wrote: But now i am in a bit of trouble: i packaged a woody backport of k3b. This programm tries to dlopen (=at runtime) 'libcdda_paranoia.so'. But that is only possible if package 'libcdparanoia0-dev' is installed. This would mean a dependency to a development package. Is this a bug in k3b? Should k3b try to dlopen 'libcdda_paranoia.so.0' instead? I think you should use the versioned library, yes. If the soname changes then that indicates that binary compatibility has been broken, and dlopen()ing the newer library from a program compiled to expect the older library may be unsafe. Is there a standard for so-naming (which is respected by all/ most Gnu/Linux distributions)? That depends on the library. Ideally, the upstream maintainer of the library should be in control of sonames. Cheers, -- Colin Watson [EMAIL PROTECTED]
Re: Question about libcdda_paranoia
On Wednesday 08 October 2003 16:58, Henning Moll wrote: Is this a bug in k3b? Should k3b try to dlopen 'libcdda_paranoia.so.0' instead? Is there a standard for so-naming (which is respected by all/ most Gnu/Linux distributions)? Shared object files that are private to a project are usually not named, i.e. only end in .so, and are installed into /usr/lib/something. Shared libraries in /usr/lib are, well, shared, and so require to be linked in properly. This means no package should make assumptions about their signature (provided symbols etc.) since .so is only a symlink in this case, and the only safe way of dealing with them is linking at build time. I haven't looked at k3b specifically, but if this library isn't used by anything else, it doesn't belong into /usr/lib. If it is, it shouldn't be dlopen()ed. Where can i learn more about the naming of share object files? info libtool Josef -- Play for fun, win for freedom. Linux-Info-Tag Dresden 2003: http://www.linux-dresden.de
Re: Question about libcdda_paranoia
Henning Moll [EMAIL PROTECTED] writes: But now i am in a bit of trouble: i packaged a woody backport of k3b. This programm tries to dlopen (=at runtime) 'libcdda_paranoia.so'. But that is only possible if package 'libcdparanoia0-dev' is installed. This would mean a dependency to a development package. Is this a bug in k3b? Should k3b try to dlopen 'libcdda_paranoia.so.0' instead? That's probably what I would do... Is there a standard for so-naming (which is respected by all/ most Gnu/Linux distributions)? Well, the actual process involved is something like this: you specify -lfoo on the ld (cc) command line; the linker finds and reads libfoo.so, and looks for the SONAME field in it; that soname (typically libfoo.so.2) is written into the binary; when the binary is loaded by ld.so, that looks for the libfoo.so.2 that was the soname. So in the normal process, you only need lib*.so at build time, and the major-version symlink at runtime. Plus, if the major version of the library chages, you'll probably need to change your program anyways. So I think explicitly writing in libcdda_paranoia.so.0 is actually the right thing to do. -- David Maze [EMAIL PROTECTED] http://people.debian.org/~dmaze/ Theoretical politics is interesting. Politicking should be illegal. -- Abra Mitchell
Re: Question about libcdda_paranoia
Hi! Am 2003-10-08 16:58 +0200 schrieb Henning Moll: But now i am in a bit of trouble: i packaged a woody backport of k3b. This programm tries to dlopen (=at runtime) 'libcdda_paranoia.so'. But that is only possible if package 'libcdparanoia0-dev' is installed. This would mean a dependency to a development package. I would discourage that (see below). Is this a bug in k3b? Should k3b try to dlopen 'libcdda_paranoia.so.0' instead? Yes! The suffix '0' denotes the library's SONAME. As long as it does not change, different versions of the lib must be binary compatible. OTOH, if it _does_ change, your program linking against it is likely to fail. This allows having several (major) library versions installed in parallel, but enforces that only one version of a development package can be installed so that new packages are urged to use the most recent version. Conclusion: dlopen ...so.0 and directly depend on the non-dev-package. Is there a standard for so-naming (which is respected by all/ most Gnu/Linux distributions)? I don't know exactly, sorry. I guess, yes. Where can i learn more about the naming of share object files? When I built my first library package, I consulted the 'Debian Library Packaging Guide' [1]. Not complete yet, but already very helpful. But actually, it isn't that difficult: packages containing shared libraries provide them with their soname as suffix, -dev packages add the corresponding symlink without a soname. BTW: Corrections appreciated, I'm still quite new to Debian. Have a nice day, Martin [1] http://www.netfort.gr.jp/~dancer/column/libpkg-guide/ -- Martin Pitt home: www.piware.de eMail: [EMAIL PROTECTED] signature.asc Description: Digital signature
Re: Question about libcdda_paranoia
On Wed, Oct 08, 2003 at 04:58:34PM +0200, Henning Moll wrote: On Wednesday 08 October 2003 13:27, Colin Watson wrote: No, plain .so links are only needed for build-time linking, and therefore live in development packages. Thank you for that information! But now i am in a bit of trouble: i packaged a woody backport of k3b. This programm tries to dlopen (=at runtime) 'libcdda_paranoia.so'. But that is only possible if package 'libcdparanoia0-dev' is installed. Look at the debian dir of the package you are backporting. ;) Hint - k3b-0.9/debian/patches/02_k3bcdparanoialib.dpatch Chris signature.asc Description: Digital signature
