There are some variables that controls the checkurl behavior, so you have to change these variables to change the way it works.
The variables that you can define are:
If this is set to “yes” then checkurl outputs more status messages.
This is the prefix for the email that checkurl sends to you, the default is [checkurl].
Having a prefix can be useful for configuring your MUA or your Gnus split methods see Splitting Mail in Gnus.
The prefix for the subject of sent emails.
If this is set to “yes” then the emails are converted to plain text using html2text.
This contains the options to give to diff see Invoking diff.
This contains the options to give to wget see Invoking wget.
This contains the options to give to html2text.
This contains the name of the checkursl home direcory. The default is $HOME/.checkurl.
This contains the path (including the filename) to the checkurl configuration file. The default is $HOME/.checkurl/conf.sh.
If this is set to “yes”, then only the additions in the diff are sent.
If this is set to “yes”, then all in the diff is sent but the additions.
If this is set to “yes”, then only the subtractions in the diff are sent.
If this is set to “yes”, then all in the diff is sent but the subtractions.
This contains an integer number.
The diff will not be sent if it's shorter than $CU_MIN_LINES.
This contains an integer number.
The diff will not be sent if it's longer than $CU_MAX_LINES.
The program used for HTML to Plain-Text conversion.
Recipients of the sent emails.
You can define these as environment variables, or in your configuration file (that is a shell script, $HOME/.checkurl/conf.sh by default) or using some command line options See Invoking.
Command line options overwrites the configuration file settings and the environment settings.
Configuration file settings overwrites the environment settings.