argv0 revisited...

Hi all :))

Finally, with a suitable solution at hand, I notice that the
kernel does just what I wanted to do, that is, overwriting the argv[0]. The matter is that when executing the init process, the kernel substitutes the program name, the true argv0, with the string 'init' :(( That is, I'm not able to exec'ing myself again, because I no longer know what is the binary name!

How can I know, more or less portably, which is the name of the
disk binary corresponding to my core image? Since 'proc' is not mounted at this time, I cannot consult my mappings not my 'exe' link. Since this init is run as root, any that root can do is welcome. Although I would like a portable solution, any solution that works under *any* Linux kernel is welcome...

BTW, is the argv0 mangling for 'init' mandatory or POSIX or
standard or...?

Thanks a lot :)

Raúl