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python works fine!</div>
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Thanks a lot, Mantas.</div>
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BR.<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>发件人:</b> Mantas Mikulėnas <grawity@gmail.com><br>
<b>发送时间:</b> 2021年10月23日 6:42<br>
<b>收件人:</b> DHAIY DHAIY <dhaiy@msn.com><br>
<b>抄送:</b> systemd-devel@lists.freedesktop.org <systemd-devel@lists.freedesktop.org><br>
<b>主题:</b> Re: [systemd-devel] 回复: Is it possible to send a string to the journal of one specific systemd unit</font>
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<div dir="ltr">This option was added with util-linux v2.25 in 2014. If you're using an older version or the Busybox `logger` instead, well, it won't have that.
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<div>The alternative is to write your own C tool that uses libsystemd and calls <a href="https://manpages.debian.org/testing/libsystemd-dev/sd_journal_send.3.en.html">
sd_journal_send</a>() with the correct fields (libsystemd is definitely going to be present), or a Python tool that uses systemd.journal.send(). (Or maybe call libsystemd through python ctypes or whatever other FFI mechanism is available.)</div>
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<div dir="ltr" class="x_gmail_attr">On Fri, Oct 22, 2021 at 4:32 PM DHAIY DHAIY <<a href="mailto:dhaiy@msn.com">dhaiy@msn.com</a>> wrote:<br>
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Thanks a lot Mantas.</div>
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But in my sytem, logger does not have "--journal".</div>
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Are you aware of other tools from bash which can be used?</div>
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BR<br>
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<div id="x_gmail-m_4190535454060497493divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> Mantas Mikulėnas <<a href="mailto:grawity@gmail.com" target="_blank">grawity@gmail.com</a>><br>
<b>发送时间:</b> 2021年10月22日 18:45<br>
<b>收件人:</b> DHAIY DHAIY <<a href="mailto:dhaiy@msn.com" target="_blank">dhaiy@msn.com</a>><br>
<b>抄送:</b> <a href="mailto:systemd-devel@lists.freedesktop.org" target="_blank">systemd-devel@lists.freedesktop.org</a> <<a href="mailto:systemd-devel@lists.freedesktop.org" target="_blank">systemd-devel@lists.freedesktop.org</a>><br>
<b>主题:</b> Re: [systemd-devel] 回复: Is it possible to send a string to the journal of one specific systemd unit</font>
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<div dir="ltr">If you have root privileges (i.e. UID 0), then yes, you can send a journal message with the "OBJECT_SYSTEMD_UNIT=myservice.service" field and journalctl will automatically look for that.
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<div>In C, specify the field when calling sd_journal_sendv(); in bash you can use `logger --journal`:</div>
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<div><font face="monospace">(echo "OBJECT_SYSTEMD_UNIT=sshd.service";<br>
echo "MESSAGE=Hello world!") | sudo logger --journal</font><br>
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<div dir="ltr">On Fri, Oct 22, 2021 at 11:43 AM DHAIY DHAIY <<a href="mailto:dhaiy@msn.com" target="_blank">dhaiy@msn.com</a>> wrote:<br>
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<p>Saying we have a systemd unit named "myservice". <br>
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<p>we can use <strong>journalctl -u myservice</strong> to inspect the logs generated by myservice.</p>
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<p>But is there a way to insert one string from command-line into myservice's journal so that it can be seen by
<strong>journalctl -u myservice</strong> later?</p>
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<font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> DHAIY DHAIY<br>
<b>发送时间:</b> 2021年10月22日 16:40<br>
<b>收件人:</b> <a href="mailto:systemd-devel@lists.freedesktop.org" target="_blank">
systemd-devel@lists.freedesktop.org</a> <<a href="mailto:systemd-devel@lists.freedesktop.org" target="_blank">systemd-devel@lists.freedesktop.org</a>><br>
<b>主题:</b> Is it possible to send a string to the journal of one specific systemd unit</font>
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<p>Saying we have a systemd unit named "myservice". <br>
</p>
<p>we can use <strong>journalctl -u myservice</strong> to inspect the logs generated by myservice.</p>
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<p>But is there a way to insert one string from command-line into myservice's journal so that it can be seen by
<strong>journalctl -u myservice</strong> later?</p>
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-- <br>
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<div dir="ltr">Mantas Mikulėnas</div>
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-- <br>
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<div dir="ltr">Mantas Mikulėnas</div>
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