Lennart Poettering
5686391b00
Users are often surprised that "systemd-run" command lines like "systemd-run -p User=idontexist /bin/true" will return successfully, even though the logs show that the process couldn't be invoked, as the user "idontexist" doesn't exist. This is because Type=simple will only wait until fork() succeeded before returning start-up success. This patch adds a new service type Type=exec, which is very similar to Type=simple, but waits until the child process completed the execve() before returning success. It uses a pipe that has O_CLOEXEC set for this logic, so that the kernel automatically sends POLLHUP on it when the execve() succeeded but leaves the pipe open if not. This means PID 1 waits exactly until the execve() succeeded in the child, and not longer and not shorter, which is the desired functionality. Making use of this new functionality, the command line "systemd-run -p User=idontexist -p Type=exec /bin/true" will now fail, as expected.
systemd - System and Service Manager
Details
General information about systemd can be found in the systemd Wiki.
Information about build requirements are provided in the README file.
Consult our NEWS file for information about what's new in the most recent systemd versions.
Please see the HACKING file for information how to hack on systemd and test your modifications.
Please see our Contribution Guidelines for more information about filing GitHub Issues and posting GitHub Pull Requests.
When preparing patches for systemd, please follow our Coding Style Guidelines.
If you are looking for support, please contact our mailing list or join our IRC channel.
Stable branches with backported patches are available in the stable repo.