Terminate at.at() stdin with a trailing newline#69768
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at.at() piped the command to `at` without a trailing newline. Distro-patched `at` on Fedora/RHEL/CentOS (Fedora at-3.2.2-shell.patch, BZ 486844) writes its job delimiter immediately after the last stdin byte, so with no trailing newline the delimiter concatenates onto the final command (e.g. `shutdown -r nowmarcinDELIMITER7f94e9f4`), producing a job that never runs. Append a single newline after building stdin, covering both the tagged and untagged branches. This matches the newline a normal `echo cmd | at now` pipe already sends, so it is benign on Debian/Ubuntu/BSD. Fixes saltstack#58510
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What does this PR do?
at.at()builds the command string it pipes toatviacmd.run(..., stdin=stdin, python_shell=False)but never terminates it with a newline. This PR appends a single trailing newline after the stdin is assembled, covering both the tagged (tag=) and untagged branches in one place.What issues does this PR fix or reference?
Fixes #58510
Previous Behavior
On distributions that ship the Fedora-patched
at(Fedora/RHEL/CentOS; Fedoraat-3.2.2-shell.patch, Red Hat BZ 486844 / BZ 2070450),atwrites its job delimiter withfprintf(fp, "marcinDELIMITER%08lx\n", i)immediately after the last byte of stdin. Because Salt sent no trailing newline, the delimiter concatenated onto the final command, e.g.shutdown -r nowmarcinDELIMITER7f94e9f4, producing an invalid job that silently never executed. Reproduced by the maintainer and by a baresubprocessrepro in the issue thread.New Behavior
A trailing newline is appended to the stdin, so the delimiter lands on its own line and the command runs. This matches the newline a normal
echo cmd | at nowshell pipe already sends, so behaviour is unchanged on Debian/Ubuntu/BSD and on any non-patchedat.Merge requirements satisfied?
changelog/58510.fixed.md)at.at('12:05am', '/sbin/reboot', tag='reboot')), an inverse test asserting the command payload is preserved and not double-newlined (passes with and without the fix), and peripheral coverage of the command-list andrunas/python_shellhandling.[NOTE] Please review Salt's Contributing Guide for best practices.
Commits signed with GPG?: No