15:49 <anarcat> so i found a *really* weird bug

15:49 <anarcat> i'm not sure if it's in golang, g10k, or both foot and alacritty

15:49 <anarcat> but if you're on a debian testing or unstable system right now and run `apt install g10k ; g10k -version` on foot or alacritty, it hangs

15:49 <anarcat> in gnome-terminal, it doesn't

15:50 <anarcat> https://github.com/xorpaul/g10k/issues/230#issuecomment-2653821669

15:50 <anarcat> it looks like this system call never returns openat(AT_FDCWD, "/dev/tty", O_WRONLY|O_CLOEXEC)

16:04 <dnkl> I have a hard time seeing how a stalling syscall can be the terminals fault...

16:08 <anarcat> that's such a weird bug

16:08 <anarcat> but the reality is that it happens only in some terminals

16:09 <dnkl> could be related somehow to the application doing different things depending on terminal? i.e using a different set of terminal features?

16:12 <anarcat> i guess it's possible, but g10k doesn't do much with the terminal

16:12 <anarcat> it might do colors and probe for that

16:19 <dnkl> to my knowledge, openat can't not return. it smells now like a mutex deadlock, but I don't see how that could cause strace to think openat is stuck

16:20 <dnkl> s/now/more

16:20 <dnkl> interesting bug nevertheless

20:09 <Arnavion> Maybe it's being opened multiple times and some circumstances cause the second one to block

20:10 <Arnavion> If it really is stuck in openat then /proc/$pid/stack might give a hint

23:18 <ovf> anarcat: in your strace, the openat completes two lines down. strace -f output is ordered by time, which means that traces of syscalls from different processes may interleave. this is what '<unfinished ...>' means -- the current syscall is still running but strace needs to print something else. it then continues with '<... $call resumed>'.

23:19 <ovf> first token on a line of strace -f output is pid. you might also be interested in the -ff option if you find -f output confusing

23:24 <ovf> dnkl: you were spot on here, but in general open can of course block. e.g. mkfifo foo;strace cat foo