Which command could you use to verify whether a crontab file exists for the thobbs user?
I have a Show
It's supposed to run every day at 7:30a est. I don't want to have to wait hours to see if it runs. Aside from changing the time it runs, are there other places I can look to ensure that the script will run at the desired time? I basically want to ensure the crontab file has been loaded in Thanks! Edit: When I Is it possible to check for a file existence in a crontab oneliner, and only execute a script if that file existed? Pseudocode:
asked Jul 28 at 11:51
2 Use an ordinary test for existence, then run the script if the test succeeds.
or
Or, using the short-circuit syntax. Doing it this way would cause the job to fail if the file does not exist (which may trigger an email from the cron daemon):
or
You could use the answered Jul 28 at 11:53
Kusalananda♦Kusalananda 285k32 gold badges566 silver badges859 bronze badges 7 In case you want to adapt full Checking if the path is a file can be a bit more complicated, as the direct test like Option 1 One knows that the file
will never be empty allows for using Option 2 If the file may also be of zero size and one needs to check for mere existence and it being a file, one could test for the existence of the path and it not being a directory:
Where answered Jul 28 at 13:48
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Atrm 2,3 If a system is down at the time of a recurring regularly scheduled task is supposed to run, which task scheduling service will run the task when the system is back up again? anacron What is the full path and filename of the file that is used to schedule tasks for the anacron daemon? /etc/anacrontab You have anacrontab file with the following settings: RANDOM_DELAY=35 START_HOURS_RANGE=17-23 #period in days delay in minutes job-identifier command 1 5 cron.daily nice run-parts /etc/cron.weekly 7 20 cron.weekly nice run-parts /etc/cron.weekly @monthly 50 cron.monthly nice run-parts /etc/cron.monthly Between which hours of the day will tasks schedule with anacron start to run? If the system was down during the time period a weekly task was scheduled to run, what is the minimum amount of time anacron will wait, after the system is back up, before running the task? If the "delay in minutes" for daily tasks is 5 minutes, how much time will anacron add to the delay of 5 minutes before the scheduled daily task? Between 5 pm and 11 pm 20 minutes A randomly chosen number of minutes between 0 and 35 What service does cron rely on to run the scripts in the /etc/cron.daily, /etc/cron.weekly, and /etc/cron.monthly directories? anacron Anacron creates a timestamp file that tells you the last time a regularly scheduled job was run. What is the full path and name of the directory that contains these timestamp files? /var/spool/anacron You need to install an email server. Which of the following applications are valid Linux email applications? Sendmail and Postfix What do you enter at the command prompt to display the contents of an MTA mail queue? mailq Which of the following MTAs use the QMQP and QMTP protocols? qmail Which of the following MTAs are modular? Postfix and qmial By default, which protocol is used by an MTA to send messages to other MTAs? 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DELETE FROM shirts WHERE color=’pink’ AND type =’polo’ AND gender=’male’; Records for men’s pink polo shirts will be removed from the shirts table Which command should you use to edit the crontab file for the Gshant user account?Linux + Exam 2.3. Which crontab option should you use to display the contents of the crontab file for the current user?The crontab -l command displays the contents of a crontab file much the same way that the cat command displays the contents of other types of files. You do not have to change the directory to /var/spool/cron/crontabs directory (where crontab files are located) to use this command.
Which command displays the Ppid?The “pstree” command is a good approach to identify the parent process ID (PPID) as it shows the parent-child relationship in a tree hierarchy.
What command would you enter at the command prompt to start the gedit program in the background?You can stop, resume, and move jobs to the background or foreground as needed. Let's resume gedit in the background and free up a prompt to run other commands. You can do this using the bg command, followed by job ID (notice [1] from the output of jobs above. [1] is the job ID).
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