Problem in core_files_upload API

by Aniket Sankpal.  

I am using core_files_upload API to upload files into moodle.

But it is giving an error "File not specified"

Below is my API call URL.

http://mymoodle.com/webservice/rest/server.php?moodlewsrestformat=json&wstoken=mytokennumber&wsfunction=core_files_upload&contextlevel=user&instanceid=3972&component=user&filearea=draft&itemid=9989&filepath=/&filename=p01.jpeg&filecontent=hello

Can anyone suggest? 

How to use core_files_upload Web service to upload files?