HSTS (HTTP Strict Transport Security) means that an HTTPS server can instruct
the client to not contact it again over clear-text HTTP for a certain period
into the future. libcurl will then automatically redirect HTTP attempts to
such hosts to instead use HTTPS. This is done by libcurl retaining this
knowledge in an in-memory cache.
Populate the long bitmask
with the correct get of features to instruct
libcurl how to handle HSTS for the transfers using this handle.
The bitmask
parameter can be a combination of the following flags:
#CURLHSTS_ENABLE
-
Enable the in-memory HSTS cache for this handle.
#CURLHSTS_READONLYFILE
-
Make the HSTS file (if specified) read-only - makes libcurl not save the cache to the file when closing the handle.