Hi Ludo, Ludovic Courtès <l...@gnu.org> writes:
> Unless I’m mistaken, we can remove the ‘scm_dynwind_sigaction’ calls > from ‘scm_system_star’: now that we use ‘posix_spawn’, this is all taken > care of. > > This can be seen by running: > > strace -o /tmp/log.strace -f guile -c '(system* "/bin/sh" "-c" "echo foo > $$")' > > … which shows pre-fork signal blocking (this is > ‘internal_signal_block_all’ in spawni.c in glibc) followed, in the child > (PID 28592 here), by a long series of ‘sigaction’ calls to reset > handlers to their default behavior: > > --8<---------------cut here---------------start------------->8--- > 28586 rt_sigprocmask(SIG_BLOCK, ~[], [], 8) = 0 > 28586 clone3({flags=CLONE_VM|CLONE_VFORK, exit_signal=SIGCHLD, > stack=0x7f73b39b2000, stack_size=0x9000}, 88 <unfinished ...> > 28592 rt_sigprocmask(SIG_BLOCK, NULL, ~[KILL STOP], 8) = 0 > 28592 rt_sigaction(SIGHUP, NULL, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=0}, 8) = 0 > 28592 rt_sigaction(SIGHUP, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=SA_RESTORER, sa_restorer=0x7f73b432d2a0}, NULL, 8) = 0 > 28592 rt_sigaction(SIGINT, NULL, {sa_handler=SIG_IGN, sa_mask=[], > sa_flags=SA_RESTORER, sa_restorer=0x7f73b432d2a0}, 8) = 0 > 28592 rt_sigaction(SIGQUIT, NULL, {sa_handler=SIG_IGN, sa_mask=[], > sa_flags=SA_RESTORER, sa_restorer=0x7f73b432d2a0}, 8) = 0 > 28592 rt_sigaction(SIGILL, NULL, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=0}, 8) = 0 > 28592 rt_sigaction(SIGILL, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=SA_RESTORER, sa_restorer=0x7f73b432d2a0}, NULL, 8) = 0 > 28592 rt_sigaction(SIGTRAP, NULL, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=0}, 8) = 0 > 28592 rt_sigaction(SIGTRAP, {sa_handler=SIG_DFL, sa_mask=[], > sa_flags=SA_RESTORER, sa_restorer=0x7f73b432d2a0}, NULL, 8) = 0 > --8<---------------cut here---------------end--------------->8--- > > Josselin, can you confirm? Yes, I believe this is all taken care of by our use of posix_spawn (which was the point in the first place :) ). Best, -- Josselin Poiret
signature.asc
Description: PGP signature