First, Introduction
The readelf is used to display information about one or more of the ELF-formatted target files, and its options allow you to control what information is displayed. The Elf-file (s) here represent the files that are being inspected. Can support 32-bit, 64-bit elf format files, but also support the document containing ELF files (this is generally referred to as the use of AR command to package some elf files, such as LIB*.A, such as the "Static Library" file).
This program is similar to the one provided by Objdump, but the information it displays is more specific, and it does not rely on the BFD library (the BFD library is a GNU project whose goal is to use a unified interface to handle different target files), So even if there is any bug in the BFD library, it will not affect the Readelf program.
Second, the option
http://blog.chinaunix.net/uid-9525959-id-2001833.html
Third, examples
http://blog.chinaunix.net/uid-9525959-id-2001833.html
Linux readelf Commands