native: Use WNOHANG before signaling #13131
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It turns out that on linux, and possibly other platforms, child processes will continue to accept signals until they have been *reaped*. This means that once the child has exited, it will succeed to receive signals until waitpid() has been invoked on it. This is unfortunate behavior, and differs from what is seen on OSX and windows. This commit changes the behavior of Process::signal() to be the same across platforms, and updates the documentation of Process::kill() to note that when signaling a foreign process it may accept signals until reaped. Implementation-wise, this invokes waitpid() with WNOHANG before each signal to the child to ensure that if the child has exited that we will reap it. Other possibilities include installing a SIGCHLD signal handler, but at this time I believe that that's too complicated. Closes rust-lang#13124
bors
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Mar 28, 2014
It turns out that on linux, and possibly other platforms, child processes will continue to accept signals until they have been *reaped*. This means that once the child has exited, it will succeed to receive signals until waitpid() has been invoked on it. This is unfortunate behavior, and differs from what is seen on OSX and windows. This commit changes the behavior of Process::signal() to be the same across platforms, and updates the documentation of Process::kill() to note that when signaling a foreign process it may accept signals until reaped. Implementation-wise, this invokes waitpid() with WNOHANG before each signal to the child to ensure that if the child has exited that we will reap it. Other possibilities include installing a SIGCHLD signal handler, but at this time I believe that that's too complicated. Closes #13124
flip1995
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Jul 25, 2024
…lexendoo Reduce typo count. changelog: none
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It turns out that on linux, and possibly other platforms, child processes will
continue to accept signals until they have been reaped. This means that once
the child has exited, it will succeed to receive signals until waitpid() has
been invoked on it.
This is unfortunate behavior, and differs from what is seen on OSX and windows.
This commit changes the behavior of Process::signal() to be the same across
platforms, and updates the documentation of Process::kill() to note that when
signaling a foreign process it may accept signals until reaped.
Implementation-wise, this invokes waitpid() with WNOHANG before each signal to
the child to ensure that if the child has exited that we will reap it. Other
possibilities include installing a SIGCHLD signal handler, but at this time I
believe that that's too complicated.
Closes #13124