iphone linux - How do I determine the target architecture of static library (.a) on Mac OS X?




3 Answers

Another option is lipo; its output is brief and more readable than otool's.

An example:

% lipo -info /usr/lib/libiodbc.a 
Architectures in the fat file: /usr/lib/libiodbc.a are: x86_64 i386 ppc
% lipo -info libnonfatarchive.a
input file libnonfatarchive.a is not a fat file
Non-fat file: libnonfatarchive.a is architecture: i386
%
link dynamic

I'm interested in verifying if a given iPhone static library has been built for ARM or Intel.

It's more curiosity than anything. Is there some kind of Mac OS X or BSD specific tool to do this? This post gives an example in Linux.




As mentioned earlier, file does not always work. otool -hv -arch all is probably the closest thing that is guaranteed to work - it gives architecture information for every single object file in the library.

Example:

% otool -hv /sw/lib/libfftw3.a
Archive : /sw/lib/libfftw3.a
/sw/lib/libfftw3.a(align.o):
Mach header
      magic cputype cpusubtype  caps    filetype ncmds sizeofcmds      flags
MH_MAGIC_64  X86_64        ALL  0x00      OBJECT     3        336 SUBSECTIONS_VIA_SYMBOLS
/sw/lib/libfftw3.a(alloc.o):
Mach header
      magic cputype cpusubtype  caps    filetype ncmds sizeofcmds      flags
MH_MAGIC_64  X86_64        ALL  0x00      OBJECT     3        416 SUBSECTIONS_VIA_SYMBOLS
...



This bash script will help you programmatically get a list of architectures into a variable.

list_archs.sh:

#! /bin/bash
lipo -info $1 | sed -En -e 's/^(Non-|Architectures in the )fat file: .+( is architecture| are): (.*)$/\3/p'

Usage example:

./list_archs.sh /usr/lib/libc.dylib
x86_64 i386



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