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How To Display Just The HTTP Response Code In Command Line Curl


Posted by Artem Russakovskii on June 10th, 2010 in Linux, Tips

Updated: September 8th, 2011

Today, I was looking for a quick way to see HTTP response codes of a bunch of urls. Naturally, I turned to the curl command, which I would usually use like this:

curl -IL "URL"

This command would send a HEAD request (-I), follow through all redirects (-L), and display some useful information in the end. Most of the time it's ideal:

curl -IL "http://www.google.com"
 
HTTP/1.1 200 OK
Date: Fri, 11 Jun 2010 03:58:55 GMT
Expires: -1
Cache-Control: private, max-age=0
Content-Type: text/html; charset=ISO-8859-1
Server: gws
X-XSS-Protection: 1; mode=block
Transfer-Encoding: chunked

However, the server I was curling didn't support HEAD requests explicitly. Additionally, I was really only interested in HTTP status codes and not in the rest of the output. This means I would have to change my strategy and issue GET requests, ignoring HTML output completely.

Curl manual to the rescue. A few minutes later, I came up with the following, which served my needs perfectly:

curl -sL -w "%{http_code} %{url_effective}\\n" "URL" -o /dev/null

Here is a sample of what comes out:

curl -sL -w "%{http_code} %{url_effective}\\n" "http://www.amazon.com/Kindle-Wireless-Reading-Display-Generation/dp/B0015T963C?tag=androidpolice-20" -o /dev/null
 
200 http://www.amazon.com/Kindle-Wireless-Reading-Display-Generation/dp/B0015T963C

Here, -s silences curl's progress output, -L follows all redirects as before, -w prints the report using a custom format, and -o redirects curl's HTML output to /dev/null.

Here are the other special variables available in case you want to customize the output some more:

  • url_effective
  • http_code
  • http_connect
  • time_total
  • time_namelookup
  • time_connect
  • time_pretransfer
  • time_redirect
  • time_starttransfer
  • size_download
  • size_upload
  • size_header
  • size_request
  • speed_download
  • speed_upload
  • content_type
  • num_connects
  • num_redirects
  • ftp_entry_path

Is there a better way to do this with curl? Perhaps, but this way offers the most flexibility, as I am in control of all the formatting.

● ● ●
Artem Russakovskii is a San Francisco programmer and blogger. Follow Artem on Twitter (@ArtemR) or subscribe to the RSS feed.

In the meantime, if you found this article useful, feel free to buy me a cup of coffee below.