determine if a shared library is compiled as 32bit or 64bit

file -L <library> | grep -q '64-bit' && echo 'library is 64 bit' || echo 'library is 32 bit'
file displays a files type the -L flag means follow sym-links (as libraries are often sym-linked to another this behavior is likely preferred) more complex behavior (*two* grep commands!) could be used to determine if the file is or is not a shared library.

-3
By: infinull
2010-03-07 06:31:35

1 Alternatives + Submit Alt

  • Determines the flavor of a shared library by looking at the addresses of its exposed functions and seeing if they are 16 bytes or 8 bytes long. The command is written so the library you are querying is passed to a variable up font -- it would be simple to convert this to a bash function or script using this format. Show Sample Output


    2
    libquery=/lib32/libgcc_s.so.1; if [ `nm -D $libquery | sed -n '/[0-9A-Fa-f]\{8,\}/ {p; q;}' | grep "[0-9A-Fa-f]\{16\}" | wc -l` == 1 ]; then echo "$libquery is a 64 bit library"; else echo "$libquery is a 32 bit library"; fi;
    birnam · 2010-03-07 04:24:08 0

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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