I don't understand the "module called cron" part of your question. I believe you are confused, cron
is a service on Linux and other Unix systems configured thru crontab
.
A crontab(5) entry is defined by a time and date and a command to run.
On Linux and Posix systems, you cannot execute or run an URL. Running something involves the execve(2) system call, which requires an executable file path (and arguments).
Perhaps you want to retrieve some URL using the HTTP protocol. You might use a command-line HTTP client, like wget
or curl
.
So perhaps the command you want to run in your crontab might be
wget http://www.xyz.com/controllera/functiona
but you could use curl
My guess is that you are confused, and don't understand well enough your question. Consider reading some material.
For example, to retrieve that URL once a day at 3 pm, you would have the following crontab entry:
# run everyday at 3 pm a GET HTTP request
0 15 * * * /usr/bin/wget http://www.xyz.com/controllera/functiona
Use the crontab(1) command to configure your crontab (which may contain several entries, and several variable definitions, so you may have to edit it).