> You could use a conditional breakpoint within the debugger, but they can be slow and for me historically unreliable, but this little snippet gives you your own conditional breakpoint that works without fail.

In theory, you can make conditional breakpoints very fast using an in-process agent. For GDB (for instance) this gives the ability to evaluate conditional breakpoints within the process itself, rather than switching back to GDB: https://sourceware.org/gdb/current/onlinedocs/gdb.html/In_00...

I've always found the GDB documentation to be a bit vague about how you set up the in-process agent but I found this: (see 20.3.4 "Tracepoints support in gdbserver") https://sourceware.org/gdb/current/onlinedocs/gdb.html/Serve...

When we implemented in-process evaluation of conditional breakpoints in UDB (https://undo.io/products/udb/) it made the software run about 3000x faster than bare GDB with a frequently-hit conditional breakpoint in place. In principle, with a setup that just uses GDB and in-process evaluation you should do even better.