Messages in this thread | | | From | Wolfgang Draxinger <> | Subject | Does SCM_RIGHTS limit on fd array apply to a particular cmsghdr or the whole ancillary data? | Date | Wed, 9 Dec 2020 20:23:58 +0100 |
| |
Hi,
in the documentation on SCM_RIGHTS the maximum number of file descriptors that can be passed is described as (release 5.09 of the Linux man-pages project):
| SCM_RIGHTS | Send or receive a set of open file descriptors from another | process. The data portion contains an integer array of the file | descriptors. | (...) | The kernel constant SCM_MAX_FD defines a limit on the number of | file descriptors in the array. Attempting to send an array | larger than this limit causes sendmsg(2) to fail with the error | EINVAL.
In my reading this might be interpreted as SCM_MAX_FD per SCM_RIGHTS cmsghdr, xor SCM_MAX_FD per sendmsg. It would be good to know, which one it is. So which is the proper strategy if I have to pass more than SCM_MAX_FD file descriptors between processes?
Cheers, Wolfgang
| |