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Signal Emission subsection, INTERFACE field is referenced as header in last sentence:<div><div class="gmail-titlepage" style="color:rgb(0,0,0);font-family:"Times New Roman";font-size:medium"><div><div><h4 class="gmail-title">Signal Emission</h4></div></div></div><p style="color:rgb(0,0,0);font-family:"Times New Roman";font-size:medium">Unlike method calls, signal emissions have no replies. A signal emission is simply a single message of type <code class="gmail-literal">SIGNAL</code>. It must have three header fields: <code class="gmail-literal">PATH</code> giving the object the signal was emitted from, plus <code class="gmail-literal">INTERFACE</code> and <code class="gmail-literal">MEMBER</code> giving the fully-qualified name of the signal. The <code class="gmail-literal">INTERFACE</code> <span style="background-color:rgb(255,255,0)">header</span> is required for signals, though it is optional for method calls.</p></div><div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div>-------------------------------------------------------------------------------<br></div><div><a href="https://chetverovod.medium.com/" target="_blank">https://chetverovod.medium.com/</a></div><div><a href="https://habr.com/ru/users/chetverovod/posts/" target="_blank">https://habr.com/ru/users/chetverovod/posts/</a><br><div><br></div><div><br></div></div></div></div></div></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br> <table style="border-top:1px solid #d3d4de">
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