Set the signal mask before forking #104
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I can't think of a good way to test this, looks good to me though /me merges |
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Fixes #102
We don't currently set the signal mask before forking. If the child process exits very quickly (probably most probable when the child fails to exec, which is the test we saw it in), the parent might receive
SIGCHLDbefore it has set the mask and thus never wait on the child.Any suggestions on writing tests for this? It's a hard race to force (it takes about 5000 spawns of dumb-init on my machine).
After this change I haven't been able to reproduce after 100,000 spawns. This is also what some other init systems do, such as sinit.