Slack API - create a post using curl

we can post messages using the slack api. how can i "create post" via slack api on command line interface?

ref: third element "create post" http://gyazo.com/fc00f2ba2af66b4d6843e89a24c33be3

I have tried the following query as follows.

curl -F file=@post_contents.txt -F channels=sample -F token=SOME_SLACK_TOKEN -F filetype=posts -F title=some_title https://slack.com/api/files.upload

      

        
        
        
      

    

I want to not create a text file, but create a post. it's better