debug scheme via Ethernet and gdb or gdb-stub

[xyluo]

Hello,
Some times it is useful to debug application via ethernet based on standard gdb 
protocol. But currently the gdb or gdb-stub was not found in nuttx's apps 
tarball. If gdb-stub would be ported to nuttx as a user program, what else need 
to be done to support this scheme? and can nuttx provide the functions required 
by gdb-stub? It seems that nuttx does not provide the system call 'ptrace'.
Best regards,xyluo