To save breakpoint definitions to a file use the
save breakpoints command.
save breakpoints [filename]
This command saves all current breakpoint definitions together with
their commands and ignore counts, into a file filename
suitable for use in a later debugging session. This includes all
types of breakpoints (breakpoints, watchpoints, catchpoints,
tracepoints). To read the saved breakpoint definitions, use the
source command (see Command Files). Note that watchpoints
with expressions involving local variables may fail to be recreated
because it may not be possible to access the context where the
watchpoint is valid anymore. Because the saved breakpoint definitions
are simply a sequence of GDB commands that recreate the
breakpoints, you can edit the file in your favorite editing program,
and remove the breakpoint definitions you’re not interested in, or
that can no longer be recreated.