Type Mac NET_SID_CLIENT_Incoming_SetEmail as BOOL __cdecl (char*, size_t)
SID packet handler: Mac body calls BNSEND_SetGlobalFlag(1) and returns 1 with plain RET. It does not read its args, but it is a handler in the SID dispatch table with the same (pPacketData, nPacketSize) shape as its Windows twin 0x00521ab0, BOOL (char* pPacketData, size_t nPacketSize), so the arity is kept.
Changes 1, applied together
Set prototype
mac 0x00052399signatureundefined NET_SID_CLIENT_Incoming_SetEmail(void)→BOOL NET_SID_CLIENT_Incoming_SetEmail(char* pPacketData, size_t nPacketSize)conventionunknown→__cdecl