How to print variable inside function

Question

I'm using RRDs::Simple function and it needs bunch of parameters.

I have placed these parameters in a special variable (parsing, sorting and calculating data from a file) with all quotes, commas and other stuff.

Of course

RRDs::create ($variable);

doesn't work.

I've glanced through all perl special variables and have found nothing.

How to substitute name of variable for the data that contained in that variable? At least could you tell me with what kind of tools(maybe another special variables) it can be done?

Sobrique · Accepted Answer · 2014-08-29 10:01:13Z

3

Assuming I'm understanding what you're asking:

You've build the 'create' data in $variable, and are now trying to use RRDs::create to actually do it?

First step is:

print $variable,"\n"; - to see what is actually there. You should be able to use this from the command line, with rrdtool create. (Which needs a filename, timestep, and some valid DS and RRA parameters)

usually, I'll use an array to pass into RRDs::create:

RRDs::create ( "test.rrd", "-s 300", 
            "DS:name:GAUGE:600:U:U", )

etc.

If $variable contains this information already, then that should be ok. The way to tell what went wrong is:

  if ( RRDs::error ) { print RRDs::error,"\n"; }

It's possible that creating the file is the problem, or that your RRD definitions are invalid for some reason. rrdtool create on command line will tell you, as will RRDs::error;

answered Aug 29, 2014 at 10:01

Sobrique

53.6k8 gold badges63 silver badges107 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Pentoxide Over a year ago

Thank you for your answer. You understand me right. Also thank you for "RRDs::error"! I've found mistake inside $variable. So, turns out I do not need "some special variable", just print errors in RRDs.

Collectives™ on Stack Overflow

How to print variable inside function

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related