Free software has titles for everyone, including sinners
Like so many inhabitants of America and Spain, at the age of nine I was sent to catechism to take my First Communion. Like most of them, I never set foot in a church again unless it was to attend a wedding or baptism. For this reason, in order to take advantage of the knowledge that insists on remaining in my memory, this list of free software to commit the deadly sins.
Of course, this blog does not encourage (some) sins to be committed. It is just an excuse to get to know some titles from the huge catalog of free and open source software. Also, imagine yourself in Hell having the punishment of reading my posts for all eternity.
What are the deadly sins
Capital sins are behaviors that according to the Catholic Church give rise to all other sins.
They are:
- Laziness: It is the refusal to make a necessary effort.
- Go to: Emotion of hate or uncontrolled anger.
- Pride: Having too high an opinion of oneself.
- Yellow: Consumption of too much food and drink.
- Lust: Using sexual pleasure for one's own gratification.
- Avarice: Desire to possess material goods in greater quantity than is necessary to survive.
- Envy: Resentment for what others have.
Free software to commit the deadly sins: Sloth
The most immediate help for the lazy is Terminal keyboard shortcuts. Some of the most useful are:
- CTRL + U: Delete all commands to the left of the cursor.
- CTRL+L: Delete all the contents of the terminal.
- CTRL+K: Delete all content to the right of the cursor.
- CTRL+W: Delete the word to the left of the cursor.
- CTRL+D: Close the current session.
- CTRL+E: Moves the cursor to the end of the line.
- CTRL+Y: Paste (Use after CTRL +U, K or W)
- TAB: Autocomplete files or commands.
- CTRL + R: Reverse the search history.
- !!: Repeat the last command typed.
- CTRL+Z: Stops the current command and runs it in the background.
- CTRL + CLOSE: Stops the execution of the command.
Automating tasks
Linux offers several tools capable of save us from having to do what the computer can do for us.
The crontab file
Cron is a daemon that is responsible for performing, without user intervention, tasks in a specific time interval. In general, these are maintenance tasks that must be carried out on a regular basis. Nothing prevents us, however, from adding some of the ones we don't want to do.
A crontab file is nothing more than a text file that specifies a series of commands to be executed on a specified datea. We have two types of crontab files: the system generated crontab file and, those created by users.
No way should we get involved; in case we have root privileges, with the system crontab file since it is used by Linux for system configuration and maintenance. This file is located at /etc/crontab.
Creating our own tasks for cron
To create our own crontab files we must define the following parameters (I list them in the order in which they should be written:
m: Represents minutes with a range from 0 to 59.
h: Indicates the execution time with a range from 0 to 23.
d: Determines the day of the month with a range from 1 to 31.
month: Specifies the month of the year with a range from 1 to 12.
s: Marks the day of the week in an interval from 0 to 6 where 0 corresponds to Sunday.
In the event that the cron job is created for the default user, the command is used
crontab –e
If it is for another user, the username must be specified with the -u parameter in the form:
crontab –u nombre de usuario –e
The first time we execute the command (from the terminal emulator) it tells us that there is no crontab file so far, so an empty one will be created. Next, it proposes us to choose one of the text editors installed on the system to edit it.
In the next article we will continue explaining the use of the cron command and we will see other tools to work less.