SlippiReplayComm cannot pick up comm file changes within the same epoch second

[jmlee337]

from discord:

following up from ⁠dolphin⁠ I've noticed that maybe the problem is that ishii does not detect a second comm file change if it's too soon after the first. To demonstrate this, here's my launcher stdout, where you can see four comms file changes

12:08:09.611 (dolphin/instance)             > wrote comms file with filePath:
12:08:21.284 (dolphin/instance)             > wrote comms file with filePath:
12:08:21.728 (dolphin/instance)             > wrote comms file with filePath: C:\Users\jmlee337\Documents\Slippi\Spectate\Game_20240312T120821.slp
12:08:51.067 (dolphin/instance)             > wrote comms file with filePath: C:\Users\jmlee337\Documents\Slippi\Spectate\Game_20240312T120851.slp

however, ishii only detects three comm file changes, seeming to miss the third one at 08:21.728

08:13:263 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-bfbe88b0cd0f190263e30bf5.json
08:21:291 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-bfbe88b0cd0f190263e30bf5.json
08:51:070 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-bfbe88b0cd0f190263e30bf5.json
08:52:519 Core\HW\EXI_DeviceSlippi.cpp:1180 W[EXI]: [Frame -123] FFW frame, behind by: 80 frames.

Times are given in seconds since the Epoch.
oh https://pubs.opengroup.org/onlinepubs/7908799/xsh/sysstat.h.html so if the file changes on the same second, it won't be detected it seems 🤔
yep this seems to be it. If I delay launchPlaybackDolphin to make sure invocations are at least 1000ms apart, it works

12:54:43.422 (dolphin/instance)             > wrote comms file with filePath:
12:55:12.947 (dolphin/instance)             > wrote comms file with filePath:
12:55:13.960 (dolphin/instance)             > wrote comms file with filePath: C:\Users\jmlee337\Documents\Slippi\Spectate\Game_20240312T125513.slp

54:47:117 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-88bda1ce88203558b51baafa.json
55:12:953 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-88bda1ce88203558b51baafa.json
55:13:974 Core\Slippi\SlippiReplayComm.cpp:159 W[EXI]: File change detected in comm file: C:\Users\jmlee337\AppData\Roaming\Electron\temp\slippi-comms-88bda1ce88203558b51baafa.json
55:15:191 Core\HW\EXI_DeviceSlippi.cpp:1180 W[EXI]: [Frame -110] FFW frame, behind by: 581 frames.

Ishiiruka/Source/Core/Core/Slippi/SlippiReplayComm.cpp

Lines 146 to 157 in 18ee345

	void SlippiReplayComm::loadFile()
	{
	// TODO: Consider even only checking file mod time every 250 ms or something? Not sure
	// TODO: what the perf impact is atm
	u64 modTime = File::GetFileModTime(configFilePath);
	if (modTime != 0 && modTime == configLastLoadModTime)
	{
	// TODO: Maybe be smarter than just using mod time? Look for other things that would
	// TODO: indicate that file has changed and needs to be reloaded?
	return;
	}