2b02747ec5
boost::process::spawn() sets SIGCHLD to SIGIGN for the child process, thus if a child PrusaSlicer spawns another subprocess and the subrocess dies, the child PrusaSlicer will not receive information on end of subprocess (posix waitpid() call will always fail). https://jmmv.dev/2008/10/boostprocess-and-sigchld.html The child instance of PrusaSlicer has to reset SIGCHLD to its default, so that posix waitpid() and similar continue to work. Fixes #5507