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@Rinzwind Hi rinz, practical question about askubuntu.com/a/412001/115155 Do you know how to run a command when iwatch sees a file change? I can't seem to figure it out from the docs. I want to run tests when code changes...

terdon

@don.joey Check out inotify instead

1

A: Open a text file in a terminal and auto-refresh it whenever it is changed

As suggested in the comments, you could also use inotify though it is overkill. By far the simplest is to use watch. Here's one way to do it with inotify: Install the inotify-tools package sudo apt-get install inotify-tools Use inotifywatch to check your file for changes. Run it in a loop and...

don.joey

@terdon, thanks. not sure if I'm a fan of an infinite while true loop though

@terdon any alternative?

terdon

@don.joey There probably is in the inotify tools suite. I don't know much about it.

@don.joey if you only want it to run once when the file is changed, you don't need the loop. The loop is only so that it keeps monitoring.

Also, bear in mind that whatever you do there will be some kind of loop. How else can you get a process to run constantly?

don.joey

agreed

terdon

Either a loop or a daemon which wakes every n seconds but that's the same idea really.

don.joey

12:45 PM

only an infinite one cannot be stopped

blade19899

Dell Precision M3800 — 15" mobile workstation also available with Ubuntu 14.04

terdon

Sure it can, you just have to do it manually. Or give it a timeout or something.

If you want this to be run every time a text file changes, you kinda need an infinite loop.

Oli

This might be a more pleasing alternative... askubuntu.com/a/465835/449

don.joey

point taken, I was talking about your snippet

terdon

You might be able to do something clever like launching it in a script which then calls it again. Something like:

inotifywatch -e modify -t 1 file.txt && DO SOMETHING && foo.sh

Where foo.sh is the script itself. That might work since, in principle, it will relaunch itself each time it exits.

don.joey

12:48 PM

hmm

that's a clever solution (though it does require the script)

the manual says "inotifywatch - gather filesystem access statistics using inotify"

ByteCommander

@terdon Won't there be something like a call stack that would grow with each relaunch?

terdon

Yes, I think Oli's suggestion is exactly what you need.

overactor

Hi guys, I figured some of you might be interested in a proposal for a site over on area 51 I made about a week ago:

52

Open Source

Proposed Q&A site for questions regarding motivation, marketing, organisation and licences pertaining specifically to open source projects.

Currently in definition.

don.joey

is this really the right tool for the job?

terdon

There's an -m option for inotifywait which will make it monitor indefinitely

@ByteCommander There may very well be. I don't really know. I just thought of that now, I've never tested it.

ByteCommander

12:50 PM

@Fabby Could you please look over this answer of mine? I want to be sure that I did everything right? askubuntu.com/a/578631/367990

Fabby

reading...

terdon

@don.joey Yeah, that's what inotify is for. I was just giving you a convoluted way but Oli gave you what I'm pretty sure is The Right Way®.

ByteCommander

@terdon I don't know either. I was just thinking that every recursive task has to have a well defined end point where it stops and goes back up in the call hierarchy. There is no such break condition here, is it?

blade19899

Can I officially call myself an icon creator now?:

ByteCommander

@blade19899 Sure you have the licenses to include all those symbols in your artwork?

terdon

12:54 PM

@ByteCommander No. I would just kill it with Ctrl+C manually. Not elegant but it should work.\

Fabby

@ByteCommander: perfect answer... The OP is a help vampire and tries to drag you into solving his problem completely for him... TYou can only point him in the right direction

blade19899

@ByteCommander Haven't thought of that :/

ByteCommander

@Fabby Thanks! I just saw the gren rep icon flash up :D

Hey, it crossed the 700 line this morning! 721 c(=D

RPi's Hackintosh

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