The interface, output, and exit status convention are all taken directly from rpmdev-vercmp and dpkg --compare-versions. The implementation is different though. See test-string-util for a list of known cases where we compare strings incompatibly. The idea is that this string comparison function will be declared as "the" method to use for boot entry ordering in the specification and similar uses. Thus it's nice to allow users to compare strings.
System and Service Manager
Details
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Please see the Code Map for information about this repository's layout and content.
Please see the Hacking guide for information on how to hack on systemd and test your modifications.
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Stable branches with backported patches are available in the stable repo.