php - Crontab file is corrupted after remove an job on list? -

im using database controlled cronjobs newsletter. crontab job add / remove functions works fine, when remove job on list main trigger file not work properly. here workbench;

task list table;

id   campaign_id    remove  date                      cron_command  1        1            0     2015-04-22 17:00:00       * * * * * curl -s http://example.com/tasks.php?id=1 

main trigger file (cron.php) checking table, if date reach current date add cron_command crontab, works fine here. tasks.php file works fine , send "id1" campaign mails.

after campaign task done , mails sent successfully, above record updated to

id   campaign_id    remove  date                      cron_command  1        1            1     2015-04-22 17:00:00       * * * * * curl -s http://example.com/tasks.php?id=1 

main trigger file check remove 1 marked commands , should have remove record both side (crontab / db table). not remove command on crontab , db table, main trigger file gives error "php command error: no input file specified", "curl command error: 400 bad request", "wget command: ambiguous redirect"

crontab manager class

class crontab {      // in class, array instead of string standard input / output format.      // legacy way add job:     // $output = shell_exec('(crontab -l; echo "'.$job.'") | crontab -');      static private function stringtoarray($jobs = '') {         $array = explode("\r\n", trim($jobs)); // trim() gets rid of last \r\n         foreach ($array $key => $item) {             if ($item == '') {                 unset($array[$key]);             }         }         return $array;     }      static private function arraytostring($jobs = array()) {         $string = implode("\r\n", $jobs);         return $string;     }      static public function getjobs() {         $output = shell_exec('crontab -l');         return self::stringtoarray($output);     }      static public function savejobs($jobs = array()) {         $output = shell_exec('echo "'.self::arraytostring($jobs).'" | crontab -');         return $output;      }      static public function doesjobexist($job = '') {         $jobs = self::getjobs();         if (in_array($job, $jobs)) {             return true;         } else {             return false;         }     }      static public function addjob($job = '') {         if (self::doesjobexist($job)) {             return false;         } else {             $jobs = self::getjobs();             $jobs[] = $job;             return self::savejobs($jobs);         }     }      static public function removejob($job = '') {         if (self::doesjobexist($job)) {             $jobs = self::getjobs();             unset($jobs[array_search($job, $jobs)]);             return self::savejobs($jobs);         } else {             return false;         }     }  } 

main trigger file cron.php

/* task list modifier */ $modchr = new crontab(); $optasks = $myconn->query("select * tasks order remove desc") or die(mysqli_error($myconn)); while($optasksrs = $optasks->fetch_assoc()){     /* remove crons */     if($optasksrs['remove']==1){         if($modchr->removejob($optasksrs['cron_command'])){             $myconn->query("delete tasks id=". $optasksrs['id'] ."");         }else{             echo('command not executed');         }     }     /* add crons */     else{         if($optasksrs['date']<=date('y-m-d h:i:s')){             $modchr->addjob($optasksrs['cron_command']);         }     } } $optasks->free(); 

shortly issue; cron.php file not work after add new cron job via shell, when try run cron.php file via browser works fine. whats wrong?

regards.