I want to verify if an object has been compiled in 32-bit or 64-bit:
% readelf -h my_obj
ELF Header:
Magic: 7f 45 4c 46 01 02 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
...
Since ELF32 is displayed, does this guarantee that the object is in 32-bit mode?