On 07/18/13 22:13, Simon Paillard wrote: > Hi Michael, > > On Mon, Jul 15, 2013 at 01:52:56PM +0200, Michael Kerrisk (man-pages) wrote: >> On Sun, Apr 29, 2012 at 7:42 PM, Simon Paillard <spaill...@debian.org> wrote: >>> (but no more LD_ASSUME_KERNEL). >> >> I just drafted the following for ld.so.8 in man-pages: >> >> LD_ASSUME_KERNEL >> (glibc since 2.2.3) Each shared library can inform the >> dynamic linker of the minimum kernel ABI version that it >> requires. (This requirement is encoded in an ELF note >> section that is typically named .note.ABI-tag.) At run >> time, the dynamic linker determines the ABI version of >> the running kernel and will reject loading shared >> libraries that specify minimum ABI versions that exceed >> that ABI version. >> >> LD_ASSUME_KERNEL can be used to cause the dynamic linker >> to assume that it is running on a system with a differ‐ >> ent kernel ABI version. For example, the following com‐ >> mand line causes the dynamic linker to assume it is run‐ >> ning on Linux 2.2.5 when loading the shared libraries >> required by myprog: >> >> $ LD_ASSUME_KERNEL=2.2.5 ./myprog >> >> On systems that provide multiple versions of a shared >> library (in different directories in the search path) >> that have different minimum kernel ABI version require‐ >> ments, LD_ASSUME_KERNEL can be used to select the ver‐ >> sion of the library that is used (dependent on the >> directory search order). Historically, the most common >> use of the LD_ASSUME_KERNEL feature was to manually >> select the older LinuxThreads POSIX threads implementa‐ >> tion on systems that provided both LinuxThreads and NPTL >> (which latter was typically the default on such sys‐ >> tems). >> >> Look okay? > > Looks ok, interesting information mentioned by > http://people.redhat.com/alikins/troubleshooting/ are actual values to be used > when switching to NPTL or olf LinuxThreads.
Yes. I've never been quite sure though whether the particular kernel versions to specify for LD_ASSUME_KERNEL when selecting the threading implementation are distro-specific, so I'm reluctant to go into the detail in the page. As you note, I do hint at the 2.2.5 version in the pthreads(7): > LD_ASSUME_KERNEL happens to be documented a bit in pthreads(7) too. Yes, good to remind about that. I've added a cross reference from ld.so(8) to pthreads(7). Cheers, Michael -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
