title: bulk update local json file with jq
body: <p>I have a JSON file name <code>emoji.json</code> located in my local mac PC
  my JSON file has this structure</p>
  
  <pre><code>[
  {
      "name": "COPYRIGHT SIGN",
      "unified": "00A9-FE0F",
      "non_qualified": "00A9",
      "docomo": "E731",
      "au": "E558",
      "softbank": "E24E",
      "google": "FEB29",
      "image": "00a9-fe0f.png",
      "sheet_x": 0,
      "sheet_y": 12,
      "s": "copyright",
      "short_names": [
          "copyright"
      ],
      "text": null,
      "texts": null,
      "c": "Symbols",
      "o": 128,
      "added_in": "1.1",
      "has_img_twitter": false,
      "has_img_emojione": false,
      "has_img_messenger": false
  },
  {
      "name": "REGISTERED SIGN",
      "unified": "00AE-FE0F",
      "non_qualified": "00AE",
      "docomo": "E736",
      "au": "E559",
      "softbank": "E24F",
      "google": "FEB2D",
      "image": "00ae-fe0f.png",
      "sheet_x": 0,
      "sheet_y": 13,
      "s": "registered",
      "short_names": [
          "registered"
      ],
      "text": null,
      "texts": null,
      "c": "Symbols",
      "o": 129,
      "added_in": "1.1",
      "has_img_twitter": false,
      "has_img_emojione": false,
      "has_img_messenger": false
  }
  ...
  ]
  </code></pre>
  
  <p>and i want to remove some unwanted values so the file should became like blow.
  and i want to save this file in JSON format in my PC</p>
  
  <pre><code>[
    {
      "s": "copyright",
      "c": "Symbols",
      "o": 128
    },
    {
      "s": "registered",
      "c": "Symbols",
      "o": 129
    }
  ]
  </code></pre>
  
  <p>i know JQ could do that and i check documentation and <a href="https://jqplay.org/" rel="nofollow noreferrer">https://jqplay.org/</a>
  and i test and found out <code>map({ s, c , o })</code> could do that but i dint find how to input file and export file </p>