Crontab write silently fail

Hi,

We run into an issue where our application tried was creating a wrong job, either with escaped \n in the command or with a command over 999 characters). The crontab write did not reported any error but the crontab was empty. I did a bit of debugging and it seem that the return code of crontab is never checked.

Trying to manually feed crontab the generated file, I got the following :

$ crontab < /tmp/tmp99_buwta
"-":2: command too long
errors in crontab file, can't install.
$ echo $?
1