On 10/24/24 10:12 AM, Zhaoming Luo wrote:
On 10/21/24 9:04 PM, Samuel Thibault wrote:
By implementing the corresponding RPC, whose msgid is given by the
IOC_MSGID macro. For instance for
RTC_RD_TIME. _IOR('p', 0x09, struct rtc_time)
the group is 'p' and the command is 0x9, so the subsystem would be
140000, and the exact RPC would be 140009.
I'm quite confused about the calculation of subsystem. May I have a more
detailed process of how 140000 is calculated? Including the names of the files
in which macros is used in the calculation. Thank you
I just came across the definition in hurd/ioctls.defs :), it's (100000 +
((group) - 'f') * 4000).
Best,
Zhaoming
