There is a unix executable file and I want to read the contents of that file. It is in an unreadable format and needs to be deciphered. It does not have any extension, when I do a cat of it on the terminal its in an unreadable format.
Is there any command that I can use to decipher it or any tool that can help. Please help.
You don't need to decipher it (unless it has some binary-level obfuscation because it's an IOCCC entry). You can disassemble it using otool -tv or objdump and read what the program inside does.)
If it's unreadable with cat then it's probably an executable format such as a.out or, more likely, ELF (though it could be a different format).
If your executable is xyzzy, you should be able to find out what type it is by using file xyzzy on it, such as with:
pax> file /bin/ls
/bin/ls: ELF 32-bit LSB executable, Intel 80386,
version 1 (SYSV), dynamically linked
(uses shared libs), for GNU/Linux 2.6.18,
stripped
That file format is well documented (such as starting from here) if you search the web, and there are tools like gcb, nm, readelf and objdump which can look inside it to varying degrees, but all it's likely to deliver to you is the raw assembly language. Getting back to easily-understandable source code will be very hard.
