Re: [Dar-support] Static dar build issues again

[Denis C. <dar...@fr...>]

Le 19/01/2022 à 15:36, Robin Atwood a écrit :
> I am trying again to build a statically linked dar binary that I can
> copy to a backup usb disk and execute from an arbitrary rescue system.
> I have a Gentoo system but the dar ebuild does not bode well on the
> subject of static builds so I checked-out the Github 2.7.x branch and
> built that. I ended up with a 6MB+ binary which was promising since
> normally it is about 500K. To check if it was completely self-contained
> I moved the libdar libraries out of the library path and tested:

another way to check is to use 'file <path/to/binary>', the size is just
an indication and when you run to test you did, you must explicitely use
the path to the binary you want to test. Moreover doing the way you did,
you may assume a binary is to static because it ran once you have
removed the dynamic library while another is used from a previous
installation in another path (/usr/local/lib vs /usr/lib for example).

> 
> # ../dar_static -l backup-FULL-1642269601 -v
> ../dar_static: error while loading shared libraries: libdar64.so.6000:
> cannot open shared object file: No such file or directory

I never saw that before!
obviously the file dar_static is not statically linked... how did you
obtain it? Did you renamed a dar binary to dar_static?

> 
> So even with a static build you still need the library modules? What is
> the procedure for producing a dar module that works on, say, the
> SysResCD system?

The process to get a statically linked dar binary from its source code
is first to have installed all the static flavors of the libraries you
want dar to rely on,

then run (for example):

  mkdir -p /tmp/test
  ./configure --prefix=/tmp/test

Eventually add --disable-shared and --disable-build-html to speed up the
process. Once ./configure has completed, check the end of the output to
see whether everything is aligned to build a statically linked dar. Add
any missing static library if needed and retry.

Once all is OK from ./configure stand point, run

  make -j 4

Replace 4 by the number of CPU cores you have, or remove '-j 4' for
single threaded compilation. Then run

  make install-strip

This will strip the symbols from the binary and upx compress the binary
if you had upx available at the time you ran the ./configure script.

dar_static will be present in /tmp/test/bin

once you have copied out dar_static you can cleanup the rest using

rm -rf /tmp/test

(assuming /tmp/test was not present initially).


Cheers,
Denis






> 
> Thanks
> Robin