unix - How to get magic number of a binary file

Question

There is a magic number associated with each binary file , does anyone know how to retrieve this information from the file?

Answer 1

file <file_name>

magic numbers are usually stored in (linux):

/usr/share/file/magic

also check this link, someone was trying to use libmagic to get the information in C program, might be useful if you're writing something yourself.