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Daniel Iliev <danny@××××××××.com> skribis: |
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> Well, then I have to simplify more (because of my lack of knowledge) and |
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> ask what are the pros and cons to use PIC when building a program and a |
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> share library? |
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When a program runs it needs to know the addresses of variables, |
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subroutines, etc. A shared library can’t know those addresses until |
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run time, when it gets linked into the program. Therefore its code |
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needs to have fancy things done to it so it can be taught where to |
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find things at run time. The PIC stuff is largely overhead. A static |
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library is linked in at program build time, and so doesn’t have this |
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overhead. |
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My wild guess is that prelink would need position independent |
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executables because the build-time linker (/usr/bin/ld) doesn’t |
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know how to link a program to a shared library as if it were a static |
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library. |
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-- |
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Barry.SCHWARTZ at chemoelectric.org http://chemoelectric.org |
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Free stuff / Senpagaj varoj: http://crudfactory.com (PDF) |
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'Democracies don't war; democracies are peaceful countries.' - Bush |
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(http://www.whitehouse.gov/news/releases/2005/12/20051219-2.html) |
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