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On 09/07/2010 12:24 AM, Al wrote: |
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>>> How does a program in Gentoo know, where to look for shared libraries? |
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>> |
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>> The program doesn't know. But the runtime linker does. And those paths are |
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>> in /etc/ld.so.conf. This file gets updated automatically by portage when |
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>> needed. |
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>> |
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>> But... sometimes the program also knows and can link against libraries long |
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>> after it has started up using a dlopen() call: |
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>> |
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>> http://linux.die.net/man/3/dlopen |
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>> |
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> |
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> Thank you Nikos. I did read obout this in the Linux HOWTO: |
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> |
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> http://www.faqs.org/docs/Linux-HOWTO/Program-Library-HOWTO.html#DL-LIBRARIES |
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> |
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> But I was woundering if the /etc/ld.so.conf was only historical stuff. |
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> O.K. is not it's up-to-date. Good to know this. |
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> |
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> But it also writes that dlopen() is specific for Linux and Solaris. |
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> There would be alternatives: |
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> |
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> 1.) The glib library |
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> 2.) libltdl, which is part of GNU libtool |
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> |
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> Now I was woundering, which way would Gentoo choose or if that is not |
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> package specific at all. Are you sure dlopen() is used as a general |
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> approach on Gentoo? |
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|
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Gentoo doesn't choose anything; it's up to the programs to decide how |
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they want to load libraries at runtime. It's like asking whether Gentoo |
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chooses to use Qt or Gtk to run Firefox; well, since Firefox is a Gtk |
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application and is making calls to Gtk functions, Gentoo doesn't have a |
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say about it. |
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