tail -f for signals. Every signal any process on the box raises β who sent it, who it hit, which signal, how it was raised (kill(2), the kernel, a POSIX timer), whether the target caught it and how long its handler ran, whether it tore a blocked syscall out with EINTR β decoded off the kernel's signal tracepoints and streamed live to your terminal. No strace -f on one pid, no ptrace, no ...