Is there a program/script to modify .conf files?

Question

I want to modify a file like /etc/gdm/custom.conf from the shell or a script.

# GDM configuration storage
[xdmcp]
[debug]
[daemon]
AutomaticLoginEnable=true;
AutomaticLogin=username;

But the idea is that I can add a line to a section and it check if the section is defined, (add the definition if not), the property is defined, let it undefine (erase the line), (and delete the section header if there is no property defined), etc...

I didn't find anything except gconftool-2 but it do not explain how to modify other files. (there is a shema file there).

Answer

So the answer is NO, there isn't a program/script to achieve this, but can easyly be made for every config file, If someone do something like that, with a little database of which markup use each file, it could become really popular.

Answer 1

Augeas is a: A command line tool to manipulate configuration from the shell (and shell scripts). (among other things)

It uses lenses to transform every file to xml, give special tools to edit them, and use the lenses to write the file back in native format.

Answer 2

Edit:

Some of the config file's use INI file headers. So you could use any INI parsers to do the validation and operations.

For Example, In python, you can use ConfigParser

In Perl , user ConfigAbstract

Answer 3

In vi, search for entries with /. Press n to find the next entry. Edit the files at will.