The operating system originates many signals, but you can send signals from one process to another, or even have a process signal itself.
操作系统生成许多信号，但您可以将信号从一个进程发送到另一个进程，甚至能让某个进程给自己发送信号。
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The most likely culprits are things that transmit a signal like a cell phone or a computer operating in Wi-Fi mode which emits an electronic pulse or wave.
The most likely culprits are things that transmit a signal, like a cell phone or a computer operating in Wi-Fi mode, which emits an electronic pulse or wave.