Provided changes add option (CONFIG_EXECFUNCS_GENERATE_SYSTEM_SYMTAB) to build complete list of available functions and syscalls automatically. The symbolic table is generated in form libsymtab.a which can be reused by application or directly pull in when "g_symtab" and "g_nsymbols" variables are requested by EXECFUNCS configuration.
I have tried to follow mechanisms for library compilation in different kernel protection modes but tested only flat no-MMU build. The basic assumption is that this library and libraries providing syscall stubs and C-library functions are available in user-space context and initial application (usually NSH) registers the symbol table through IOCTL. The table can be reused then by another applications in their address space as kernel allows. Simple for flat or protected mode, I am not sure if really support in MMU mode. It is highly probable that I have made some mistake, overlooked something, but functionality is optional (should not cause troubles in any mode if disabled) and main purpose is to lower memory overhead when more applications are loaded on memory constrained system which usually use direct kernel calling without protection or address space separation. If the table should be provided by kernel to applications then makefiles has to be adjusted.
