>>>>> "Ian" == Ian Jackson <[EMAIL PROTECTED]> writes:
Ian> In general, it's not safe to use a minor version of a library Ian> lower than that with which the binary was compiled. Ian> So you if you have a library L used by both an program S Ian> which you want to compile for stable and a program U you want Ian> to try out from unstable, then you have to install the L from Ian> unstable (because U is compiled against it), and because the Ian> versions of L and L-dev have to match, you have to have the So lets make up some more details: stable: ------ libl6 version 2.1-1 contains: /usr/lib/libl.so.6.0 /usr/lib/libl.so.6 --> /usr/lib/libl.so.6.0 libl-dev depends on libl6 version 2.1-1 and contains: /usr/lib/libl.so --> /usr/lib/libl.so.6.0 progs depends on libl6 and contains: ldd /lib/libwrap.so.0 libc.so.6 => /lib/libc.so.6 (0x4000e000) libl.so.6 => /lib/libl.so.6 (0xXXXXXXXX) ------ unstable: --------- libl6 version 2.2-1 contains: /usr/lib/libl.so.6.1 /usr/lib/libl.so.6 --> /usr/lib/libl.so.6.1 libl-dev depends on libl6 version 2.2-1 and contains: /usr/lib/libl.so --> /usr/lib/libl.so.6.1 progu depends[1] on libl6 (>=2.2-1) and contains: ldd /lib/libwrap.so.0 libc.so.6 => /lib/libc.so.6 (0x4000e000) libl.so.6 => /lib/libl.so.6 (0xXXXXXXXX) --------- so progs will work with both versions of libl.so.6.* but progu will only work with libl.so.6.1, as it was compiled based on libl.so.6.1 And you want to install libl-dev version 2.2-1 on a stable system without installing libl6 version 2.2-1 at the same time? Am I right so far? If so, what is the problem with installing the unstable version of libl6? Oh, you explain it here. Ian> L-dev from unstable, but then when you compile S it ends up Ian> needing the L from unstable. So you want to be able to compile progs based on libl version 2.1-1 and progu based on libl version 2.2-1. You don't want to have to downgrade libl to version 2.1-1 just to install libl-dev 2.1-1, because that would break progu. Your proposal would (supposedly) help by allowing you to install libl-dev version 2.1-1 even though libl6 version 2.2-1 has been installed, so you can compile for the earlier version, while at the same time you can run both progu and progs. (how do you ensure that all -dev packages installed are from stable, and you haven't missed any?) Ok, Thanks, I think I understand now. Note: [1] I hope nobody disputes why this version depends is required... (things might get awkward if it was forgotten). -- Brian May <[EMAIL PROTECTED]>