curl(1) -T secret.txt 123.45.67.89
transfer a URL
-T, --upload-file <file>
       This  transfers  the  specified  local  file  to  the  remote URL. If there is no file part in the
       specified URL, Curl will append the local file name. NOTE that you must use a trailing  /  on  the
       last  directory  to  really  prove to Curl that there is no file name or curl will think that your
       last directory name is the remote file name to  use.  That  will  most  likely  cause  the  upload
       operation to fail. If this is used on a HTTP(S) server, the PUT command will be used.
source manpages: curl