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Robustify fork server launching & problem detection, part 1 #536
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This change addresses the problems (1) and (4) from the bug:
1. The fork server launches the command in the background like this:
```
int ret = system("command &");
CHECK_EQ(ret, 0);
```
However, `system()` always returns success in this case, provided it can just parse the command, because the command is run in the background and doesn't return its exit code to the subshell.
4. Even if started successfully, the fork server can still die at any moment. Centepede doesn't attempt to detect this, instead sending execution requests to an absent process, never receiving a reply, and eventually timing out.
PiperOrigin-RevId: 516385634
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Robustify fork server launching & problem detection, part 1
This change addresses the problems (1) and (4) from the bug:
The fork server launches the command in the background like this:
However,
system()always returns success in this case, provided it can just parse the command, because the command is run in the background and doesn't return its exit code to the subshell.Even if started successfully, the fork server can still die at any moment. Centepede doesn't attempt to detect this, instead sending execution requests to an absent process, never receiving a reply, and eventually timing out.