Does such a thing exist for shared objects in similar fasion to an executable packer?

Why/what for one needs a packer ?

Only for the filesize... I'm working on a library that I have to frequently upload to a server to test. Zip achieves a compression ratio of around 75%, which is impressive, but it got me wondering if there's any specially targetted tool for the job, like there is for executables.

It'd save me having to zip / unzip every time I upload it (and would probably yield an even greater ratio than zip)

maybe http://upx.sourceforge.net/ but its a stretch

WTF? forum bug it says it says if you opted to post a poll with this topic you will be redirected there or to that effect

You should also consider the -Os gcc option, and of course stripping debug symbols and the symbol table. Assuming you've already done that, how exactly do you load a compressed shared library? As far as I know, ld.so will mmap the appropriate shared libraries at run-time. You might be able to hack it and make it bunzip, also, which would allow you to bzip2 the libraries.
Kevin Barry

???

Under UNIX-like systems 'tar' and/or its better incarnation GNU tar exist.

Under UNIX-like systems 'gzip', 'bzip2', 'p7zip', 'zip' and other various compressors (including various LZMA ones) exist.

'tar' can call 'gzip' and 'bzip2' through 'z' and 'j' command line switches; I think that latest 'tar' versions know something about LZMA too.

'tar' can pack the whole directory.

'tar' can output to STDOUT while the compressors can take data from STDIN, so 'tar' can be combined with any of the above compressors.

So, why/what a specific application is needed ?

If you want one tool - write a shell alias or a script which combines/aggregates what is necessary - the amount of lines will be probably more than an order of magnitude less than in this post.

Unfortunately, upx will not work to compress shared libs. You can always use xz, bzip2 or whatever.

I was hoping that you were going to ask about be able to use compressed shared libs to run programs -exactly since upx doesn't work. Long ago, I saw a hackish way to do it by renaming and compressing the lib with whatever and then creating a wrapper with the original name which would then unpack and execute the real lib when needed.

That's the sort of thing I was after. I'm surprised there aren't any common solutions out there - not sure I want to try implementing it myself, however...

Aha. The -s option to remove the symbol table helps me a lot (80% filesize reduction).

That (and having found the ssh compression options for sFTP uploads) should do fine for now...

Already mentioned 'upx' does that:


http://linux.die.net/man/1/upx :

"Already mentioned 'upx' does that:" but not shared libs. Just try it and you'll see that it refuses to do it.