curl allows to add extra headers to HTTP requests.
The HTTP headers are used to pass additional information between the client and the server.
In this article i am showing the examples of how to add header in curl, how to add multiple headers and how to set authorization header from the Linux command line. (more…)
JFrog’s Artifactory is a binary repository manager.
The artifacts from Artifactory can be downloaded using REST API.
In this note i am showing how to download an artifact (simple file.zip) from generic Artifactory repository using curl command from the command line in Linux or from the PowerShell in Windows. (more…)
When browser connects to a website, it includes a User-Agent string in its HTTP header.
Sometimes you may need to change User-Agent with curl to access some URL as a different browser.
This is a small note on how to set a custom User-Agent with curl from the command line in Linux. (more…)
You can easily test a a website availability from the Linux command line and get the status codes from the web-server using commands like TELNET or CURL.
Execute the following command to check whether a web site is up, and what status message the web server is showing:
$ curl -Is http://www.shellhacks.com | head -1 HTTP/1.1 200 OK
Status code ‘200 OK’ means that the request has succeeded and a website is reachable.
Here is an another example that shows you how curl displays different status codes.
$ curl -Is http://shellhacks.com | head -n 1 HTTP/1.1 301 Moved Permanently
You’ll notice that if you visit: http://shellhacks.com you are redirected to http://www.shellhacks.com, because I prefer to have www in my site’s URL. I do this by implementing a 301 Redirect (Permanently moved) for any visitor who goes to http://shellhacks.com.
You can also check the availability of a particular page on the site:
$ curl -Is http://www.shellhacks.com/Bash-Colors | head -n 1 HTTP/1.1 200 OK
Read more: Status Code Definitions
You can also test website availability and get the response code using telnet command:
$ telnet www.shellhacks.com 80 Trying 91.206.200.119... Connected to www.shellhacks.com. Escape character is '^]'. HEAD / HTTP/1.0 HOST: www.shellhacks.com <PRESS ENTER> <PRESS ENTER>
You will get the output as follows:
HTTP/1.1 200 OK Server: nginx/1.1.10 Date: Sun, 26 May 2013 19:29:46 GMT ***
That also means that the website is OK.
Use one of the following commands to check your public IP address from the Linux command line.
Get your external IP address using the curl command:
$ curl ifconfig.me $ curl ip.appspot.com $ curl icanhazip.com
Get your external IP address using the wget command:
$ wget -q -O - ifconfig.me $ wget -q -O - ip.appspot.com $ wget -q -O - icanhazip.com
$ wget -q -O - checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//'
$ curl -s checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//'
$ lynx -dump checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//' | sed '/^$/d'