Re: [Take II] On SIGCHLD signal semantics

Tom Dyas (tdyas@eden.rutgers.edu)
Thu, 27 Jun 96 14:12:56 EDT


> If POSIX_SIGCHLD is #define'd in kernel/exit.c, the kernel will produce
> warnings when an application makes a wait* system call with a SIGCHLD signal
> handler it inherited from its parent, or when a child process exits while its
> parent process is still using an inherited SIGCHLD signal handler of SIG_IGN.
> These warnings are only intended to highlight the problem, and do not, by
> themselves, solve it. The warnings are:

Why use compile-time macros? The SIGCHLD behavior should be run-time
configurable using a sysctl for maximum flexibility. (If I want to
switch behaviors, then I would have to recompile my kernel. But if I
had a sysctl, I only have to change do a "echo 1 >
/proc/sys/kernel/sigchld-behavior" or something similar.)

Tom