System Settings/Task Scheduler: Difference between revisions

    From KDE UserBase Wiki
    m (Fix minor typo)
    (Split lists)
    Line 3: Line 3:


    == General Information == <!--T:1-->
    == General Information == <!--T:1-->
    Task Scheduler is a graphical front end to the standard "cron" utility. With it, commands (or "tasks") can be run at specific times, on a certain day or date, or at specific intervals (time between execution).
    Task Scheduler is a graphical front end to the standard "cron" utility. With it, commands (or "tasks") can be run at specific times, on a certain day or date, or at specific intervals (time between execution).
    [[Image:Kcron-screenshot-de.png|thumb|300px|center|Task Scheduler in Plasma 5]]
    [[Image:Kcron-screenshot-de.png|thumb|300px|center|Task Scheduler in Plasma 5]]


    Line 36: Line 38:


    <!--T:19-->
    <!--T:19-->
    * Using the buttons, choose when the command should be run. Not all parameters are required, those not needed may be left blank.
    * Using the buttons, choose when the command should be run. Not all parameters are required, those not needed may be left blank.</translate>
    <translate>
    ** Hours and Minutes are the time of day to run the task, not an interval.
    ** Hours and Minutes are the time of day to run the task, not an interval.


    Line 56: Line 59:


    <!--T:28-->
    <!--T:28-->
    * Enter the name of the variable to use. This name:
    * Enter the name of the variable to use. This name:</translate>
    ** Must consist of letters, digits, and underscore ('_') only
    <translate>
    ** Must start with a letter
    ** Must consist of letters, digits, and underscore ('_') only</translate>
    <translate>
    ** Must start with a letter</translate>
    <translate>
    ** Should not be a reserved or commonly used system variable. See https://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html for more information
    ** Should not be a reserved or commonly used system variable. See https://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html for more information



    Revision as of 08:22, 1 June 2019

    General Information

    Task Scheduler is a graphical front end to the standard "cron" utility. With it, commands (or "tasks") can be run at specific times, on a certain day or date, or at specific intervals (time between execution).

    Task Scheduler in Plasma 5

    Usage

    Task Scheduler can be started by starting the System Settings application. Select Startup and Shutdown follwed by Task Scheduler.

    Adding and Modifying tasks

    • Click New Task... to add a new task, or "Modify" to modify an existing task. The Add or modify existing task page will be displayed.
    The "Add or modify task" page of SystemSettings
    • Enter the command to be run. Click the folder icon to choose it from a dialog.
    • Enter a comment (optional). This should be descriptive, explaining what the task will do as the command may not always be obvious.
    • Click Enable this task to enable the task to run.
    • Click Run at system bootup to enable the script to run each time the system is booted.
    • Click Run every day to enable the script to run every day. This will automatically select the appropriate options.
    • Using the buttons, choose when the command should be run. Not all parameters are required, those not needed may be left blank.
      • Hours and Minutes are the time of day to run the task, not an interval.
    • When done, click OK. The task will be added and scheduled if enabled.

    Tip

    Click Run Now to run a task immediately after adding or modifying the task.


    Removing a task

    To completely remove a task, select the task from the list and click the Delete button. This will permanently remove the task.

    Environment Variables

    Sometimes a task or multiple tasks need a specific variable set, it must be added in the Environment Variables section. The cron utility uses its own environment, system-wide and user-specific variables are not used. Click New Variable to add a new variable definition, or Modify to change an existing variable.

    • The value the variable will contain. This can be a number or string.
    • Enter a brief description of the variable.

    Hints

    • All the files that are modified are located in the /etc/cron directory where there are numerous files to look at.
    • The command-line tool that allows you to have a look at the currently installed cron-jobs is
      crontab -l
      (that's the letter L).

    More Information