On Oct 12, 2011, at 6:12 PM, Alan Coopersmith wrote: > On 10/12/11 10:50 AM, Keith Packard wrote: >> 2. I'd love to figure out how to fork at the time of the error; this >> would encourage people to actually use this option regularly. >> >> posix threads makes the usual libc fork() function take the malloc >> mutex across its operations, but I wonder if syscall(SYS_fork) is >> portable enough to be used instead? > > As discussed on IRC, no, syscall() is not portable, but the libc fork() issue > seems to be a linux problem, as SUSv2/Unix98 documents fork() as safe to use > in a signal handler, but glibc does not. posix_spawn() may also be a more > portable option. > > The existing Solaris xorg_backtrace_pstack() in Xorg's os/backtrace.c has > been forking in the signal handler for a couple years now - ideally we'd > be able to mostly share the code across platforms, but I've not looked into > that.
If fork(2) in glibc isn't signal handler safe, are you sure posix_spawn(3) is in glibc? _______________________________________________ [email protected]: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: http://lists.x.org/mailman/listinfo/xorg-devel
