Curiosity and the cat

_pleasedontdothis_.jl

mem_size = 64
mem_prot = 0x40         # PAGE_EXECUTE_READWRITE
mem_type = 0x00001000   # MEM_COMMIT
 
ex_mem = ccall(:VirtualAlloc,
               Ptr{Uint8},
               (Ptr{Void}, Csize_t, Uint64, Uint64),
               C_NULL, mem_size, mem_type, mem_prot)   # call VirtualAlloc and get executable page
 
exec_arr = pointer_to_array(ex_mem, (32,2));           # consider as an array so we can write to it
                                                       # note that we make it (32,2) so that we won't
                                                       # accidentally try to resize it. Can still
                                                       # access directly up to index 64.

noreallyiwasntkidding.jl

exec_arr[1] = 0x55 # push ebp
exec_arr[2] = 0x5d # pop ebp
exec_arr[3] = 0xc3 # ret

ccall(pointer(exec_arr), Void, ())

I love that you can do this, even though it's a rather bad idea.

This is really cool. I love that I can basically write like Python and jump to raw bytes and start executing them in the same language :)