Command Line Polling
In an ideal world, we wouldn't have to poll for anything; we would always have events to trigger other functions. This isn't an ideal world, however, so it's important to know how to poll in multiple programming languages. I've covered JavaScript polling (with and without Promises), but what about command line polling? For example, ensuring MYSQL is up before attempting to perform more operations.
Here's the basic syntax:
# while ! (command here); do
while ! mysql -uroot; do
sleep 1
done
The example above performs the mysql -uroot
operation (which will fail until mysqld
is up) every second. Keep in mind the poll operation you run should be as simple as possible, just enough to know that what you want to use is available!
![Regular Expressions for the Rest of Us]()
Sooner or later you'll run across a regular expression. With their cryptic syntax, confusing documentation and massive learning curve, most developers settle for copying and pasting them from StackOverflow and hoping they work. But what if you could decode regular expressions and harness their power? In...
![From Webcam to Animated GIF: the Secret Behind chat.meatspac.es!]()
My team mate Edna Piranha is not only an awesome hacker; she's also a fantastic philosopher! Communication and online interactions is a subject that has kept her mind busy for a long time, and it has also resulted in a bunch of interesting experimental projects...
![Fx.Rotate: Animated Element Rotation with MooTools]()
I was recently perusing the MooTools Forge and I saw a neat little plugin that allows for static element rotation: Fx.Rotate. Fx.Rotate is an extension of MooTools' native Fx class and rotates the element via CSS within each A-grade browser it...
![Flexbox Equal Height Columns]()
Flexbox was supposed to be the pot of gold at the long, long rainbow of insufficient CSS layout techniques. And the only disappointment I've experienced with flexbox is that browser vendors took so long to implement it. I can't also claim to have pushed flexbox's limits, but...