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

Terminal - determine if a shared library is compiled as 32bit or 64bit
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;
2010-03-07 04:24:08
User: birnam
Functions: echo grep sed wc
2
determine if a shared library is compiled as 32bit or 64bit

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.

Alternatives

There are 6 alternatives - vote for the best!

Terminal - Alternatives
file -L <library> | grep -q '64-bit' && echo 'library is 64 bit' || echo 'library is 32 bit'
2010-03-07 06:31:35
User: infinull
Functions: echo file grep
Tags: bash
-3

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.

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