similar to \fIpoll(2)\fP's pollfd structure to be waited on in the same call.
On completion, if \fInumfds\fP is non-NULL, it will be populated with the
-total number of file descriptors on which interesting events occurred. This
+total number of file descriptors on which interesting events occured. This
number can include both libcurl internal descriptors as well as descriptors
provided in \fIextra_fds\fP.