我的删除cronjob php函数有什么问题？

Question

I'm trying to write a function that helps with deleting cron jobs, I've tried some classes from the net but it didn't work, so I'm writing it myself ,the problem that it's not removing command correctly, it's either deleting it or it's removing half of every cron job that is exist in the file!

Here's my function :

function delete_cronjob($command)
{
   $outputs = array();
    exec('crontab -l',$outputs);

    for($i=0;$i<count($outputs);$i++)
    {
        if ($outputs[$i]==$command)
            $outputs[$i]=NULL;
    }

      shell_exec('crontab -r');
      for($i=0;$i<count($outputs);$i++)
      {
          if ($outputs[$i]!=NULL)
            shell_exec('(crontab -l ; echo "'.$outputs[$i].'") |uniq - | crontab -');
      }

}

And this is the kind of cron job I use :

$command='0 0 * * * ssh -p 22 root@192.168.0.121 "cd /home/sally/;./bckp_rstr.bash _ _ 0 1 test root@192.168.0.196:/home/sally/sal_bckp/ 192.168.0.121 22 1 "';
delete_cronjob($command);

what's wrong ?

Answer 1

If it works on your system like it does on mine (Fedora) I would suggest just using file_put_contents, much less to go wrong

Also I store the cron jobs in a database, so I can flag them as active/inactive and just dump out the active ones - along with a field for comments/description of what it does

it has the downside of overwriting any crons edited manually, but I don't tend to do that. The advantage of having a store of crons that can be accessed by al our servers - there is a field that says which server(s) the crons are for - outweighs that. It also means the the list of crons is backed up along with the rest of the data, and can easily be pushed out to other machines if need be :) worth considering.