On Linux, is root privilege required to send a wake-on-lan magic packet?
If it depends on how you send the magic packet, please let me know under what situation root is required.
It depends on the program you use to send wake-on-lan packets. Some programs use raw packets, and therefore require root. Other programs embed the magic wakeup sequence in a bog standard UDP packet, and thus do not require root.
In theory it shouldn't matter what kind of packet you use, as long as there's the magic wake-on-lan sequence somewhere inside it. In practice I seem to remember that my old desktop refused to wake up when I used a Python script that sent UDP packets, but worked fine if I used a C program that used raw packets.