Make a backup of the crontab file on edition and deletion

[iTrooz]

This will help users that mistakenly run crontab -r, by providing a way to restore the crontab file

A bit related to #12

[t8m]

This is a nice idea however I'd like to see it a little bit more general - i.e., backup the previous user's crontab any time a writing to a crontab happens. Also the backup file should be placed somewhere in the home directory - I assume $(XDG_CACHE_HOME)/crontab.backup (if XDG_CACHE_HOME is set) and $HOME/.cache/crontab.backup otherwise.

[iTrooz]

I think that should be good !

[t8m]

Final nits. Plus we need the username from -u in the backup file name and also some documentation in the crontab(1) manpage.

[t8m]

Please remove the space between the cast and function name.

[iTrooz]

Other instances of (void) have a space, for example :

cronie/src/crontab.c

Line 348 in 32bced4

(void) strcpy(Host, argv[optind]);

Are you sure ?

[iTrooz]

Sure! Sorry for all these basic mistakes, it's my first time contributing C code

(I know I still have to add documentation to the man, I'll do that when I get time)

[iTrooz]

Do you want me to clean the commit tree with an interactive rebase, before integrating them in master ?

[t8m]

Do you want me to clean the commit tree with an interactive rebase, before integrating them in master ?

Yes, please squash the commits to single one with some descriptive commit message.

[t8m]

Perfect. Merging.

[iTrooz]

Thanks for being patient with me

[anthonyryan1]

This is failing on systems where $XDG_CACHE_HOME or $HOME/.cache doesn't exist yet.

Should the pull request to fix this create the .cache folder where it doesn't exist, or disable the backup when it doesn't exist?

I'm leaning towards creating .cache where missing, rather than failing.

[t8m]

This is failing on systems where $XDG_CACHE_HOME or $HOME/.cache doesn't exist yet.

Should the pull request to fix this create the .cache folder where it doesn't exist, or disable the backup when it doesn't exist?

I'm leaning towards creating .cache where missing, rather than failing.

This was reported as #173

Creating a .cache would be fine IMO.