comp.lang.idl-pvwave archive: archive » Re: openr and /get

Home » Public Forums » archive » Re: openr and /get_lun

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: openr and /get_lun [message #19740 is a reply to message #19734]

Fri, 14 April 2000 00:00

davidf
Messages: 2866
Registered: September 1996

Senior Member

Craig Markwardt (craigmnet@cow.physics.wisc.edu) writes:

> I have noticed that the use of /GET_LUN and ERROR keywords to openr is
> not as helpful as I would have hoped. Do other have this experience?
> The problem is that when an error occurs, it is hard to know whether
> the file unit was "gotten" or not.
>
> For example:
>
> pro test1
> openr, unit, filename, /get_lun, error=err
> free_lun, unit
> end
>
> If there was an error, then it is possible that UNIT was never set,
> and is hence undefined. FREE_LUN doesn't take undefined variables.
>
> If there is error checking to do, I don't know exactly what it should
> be. So I find myself explicitly doing this instead:
>
> pro test2
> get_lun, unit
> openr, unit, filename, error=err
> free_lun, unit
> end
>
> Comments?

I guess I'd use the ol' IF N_Elements(lun) NE 0 THEN Free_Lun, lun

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Toll-Free IDL Book Orders: 1-888-461-0155

Report message to a moderator

[Message index]

		Re: openr and /get_lun By: Nando Iavarone on Mon, 17 April 2000 00:00
		Re: openr and /get_lun By: majewski on Sun, 16 April 2000 00:00
		Re: openr and /get_lun By: mallors on Sun, 16 April 2000 00:00
		Re: openr and /get_lun By: davidf on Fri, 14 April 2000 00:00

Previous Topic:	Re: interactive plotting and ps output.
Next Topic:	ROUTINE_NAMES and other magic

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Sun Oct 12 13:08:53 PDT 2025

Total time taken to generate the page: 1.84011 seconds