When I start to debug with gdb I edit few breakpoints and commands into gdbinit file.
How can I change this file and load it again while I debugging without detach from process?
How can I change this file and load it again
There is nothing special about this file (other than it's automatically read by GDB at startup) -- it's just a file of GDB commands.
You can reread it with (gdb) source ~/.gdbinit
.