e68a8dd86c
This changes the SHM log format, it doesn’t use 0-bytes to separate entries anymore. Instead of using lots of printf() calls in i3-dump-log, we now do precisely one big write(). So, to be clear: i3-dump-log and i3 both need to be upgraded. Mismatching versions will lead to garbage output (no crashes of i3, just garbage output). The -f flag uses an inter-process pthread_cond_t in the shared memory header to broadcast the arrival of new messages to all i3-dump-log processes. This internally uses futexes and thus doesn’t even mean a kernel call in most cases. inter-process pthread_cond_ts require NPTL (the Native Posix Thread Library, introduce in Linux 2.6).
