July 2018
Beginner
264 pages
8h 9m
English
Content preview from Bash Cookbook
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Getting ready
In earlier recipes, we introduced the use of trap to catch signals, and the use of kill to send signals to processes. These will be explained further in this recipe, but here are three new native Bash variables:
- $$: Which returns the PID of the current script
- $?: Which returns the PID of the last job that was sent to the background
- $@ :Which returns the array of input variables (for example, $!, $2)
We are skirting around the ideas of jobs, tasks, background, and foreground as they will appear again in proper detail in a later administrative recipe.
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.