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Re: Strange UNIX or strange IDL? [message #13412 is a reply to message #13410]

Wed, 04 November 1998 00:00

davidf
Messages: 2866
Registered: September 1996

Senior Member

Harald Frey (hfrey@ssl.berkeley.edu) writes:

> IDL> print,!version
> { sparc sunos unix 5.1 Apr 13 1998}
> IDL> pwd=getenv('PWD')
> IDL> print,pwd
> /disks/sprite/disk1/hfrey/idl/image/wic
> IDL> pwd=getenv('pwd')
> IDL> print,pwd
>
> IDL>
>
> With the name argument of getenv set to capital letters I get the right
> answer, but in small letters 'pwd' returns the null string. However, if
> I use the same command on the UNIX platform I get
>
> image1 [1] pwd
> /disks/sprite/disk1/hfrey/idl/image/wic
> image1 [2] PWD
> PWD: Command not found
>
> and UNIX does not like the capital letter 'PWD'.
>
> Any explanation?

I think you are confusing the command ("pwd"), which in
UNIX (a case sensitive operating system) is always expressed
in lowercase characters, with the environment variable ("PWD")
which is always expressed in uppercase characters. (So
you can tell them apart. :-)

Here IDL is doing exactly the correct thing and getting
the Environment variable for you. When the environment
variable is undefined, you get a null string back.

If you are really just tying to get the current working
directory, here is an IDL program for you:

PRO PWD
CD, Current=thisDirectory
Print, thisDirectory
END

Wouldn't know how to get along without it. :-)

Cheers,

David

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

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[Message index]

		Re: Strange UNIX or strange IDL? By: Vap User on Mon, 09 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: LC's No-Spam Newsread on Fri, 06 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: Vap User on Fri, 06 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: davidf on Thu, 05 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: David Kastrup on Thu, 05 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: seanosea on Wed, 04 November 1998 00:00
		Re: Strange UNIX or strange IDL? By: davidf on Wed, 04 November 1998 00:00

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