1 Topic by ka9mva (edited by ka9mva 2008-01-28 16:15:38)

  • Registered: 2008-01-19
  • Posts: 13

Topic: Why multiple libasound.so in /lib?

Chumby experts,

In my investigation of running an external sound card on the Chumby, I was looking for all the ALSA components so I can upgrade them.  But I found *THREE* versions of libasound.so (ALSA sound library) in /lib.

libasound.so
libasound.so.2
libasound.so.2.0.0

Does anyone else's Chumby have these?

Also, it seems that /lib is a read-only file system.  So, is re-compiling the kernel the only way to upgrade ALSA?

Thanks

Steve

  • Duane
  • Duane
  • Blue Octy
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  • From: San Diego, CA
  • Registered: 2006-08-24
  • Posts: 8,203

Re: Why multiple libasound.so in /lib?

This is pretty common in Linux - if you do an "ls -l" you'll see that the first two are actually symbolic links to the third.

This allows one to run multiple versions of libraries if necessary - a binary that links generically to "libasound.so" will actually get "libasound.so.2.0.0", but if someone needed to use a *particular* version could include it and link to it directly.

For more info, see here.

The firmware in the chumby is built as "cramfs", a compressed, read-only file system.  This is very common in space-limited embedded devices.  There are some instructions in another thread somewher about how to extract the file system, modify it, and write it back, however, this is not supported in any way by the company, and you definitely need to be sure you know what you're doing.

You might be able to run an alternative library by setting the environment variable "LD_LIBRARY_PATH" to the search path you want.

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