topic Re: Where is env variable LPATH defined in Operating System - HP-UX

Where is env variable LPATH defined

Ken Englander — Wed, 29 Dec 2010 19:07:03 GMT

Where is LPATH set and defined? When HP-UX boots how does LPATH get set up or when a process is created?

Thanks!

Re: Where is env variable LPATH defined

Dennis Handly — Wed, 29 Dec 2010 19:27:20 GMT

This is set by the driver and you shouldn't be using it.
Do you have a reason for asking?

Re: Where is env variable LPATH defined

Ken Englander — Wed, 29 Dec 2010 19:30:28 GMT

Hi Dennis - I do not know the particulars, but we use it to link our application code. I'm not sure, but I suspect HP probably help us set it up.

The doc I have found about it does not say that it is unacceptable to use.

What driver sets it?

Thanks

Re: Where is env variable LPATH defined

James R. Ferguson — Wed, 29 Dec 2010 19:36:08 GMT

Hi Ken:

If 'LPATH' isn't set the linker uses default paths for library searches otherwise the colon-separated list of paths specified by 'LPATH" is used.

You could set and export LPATH in your profile if you like.

See the manpage for 'ld_ia' or 'ld_pa' for more information.

Regards!

...JRF...

Re: Where is env variable LPATH defined

Dennis Handly — Wed, 29 Dec 2010 19:49:18 GMT

>but we use it to link our application code. I suspect HP probably help us set it up.

If you use it, certain driver options won't work.

>does not say that it is unacceptable to use.

If you use it, you're responsible if things don't work. You should use -L instead.

>What driver sets it?

aCC/cc/c89/c99, f90, etc.

>JRF: otherwise the colon-separated list of paths specified by LPATH is used.

Instead, -L should be used for each path.

>You could set and export LPATH in your profile if you like.

Only if you want to upset the drivers. ;-)
LPATH is likely to be specific to each application you build and shouldn't be in your .profile.

Re: Where is env variable LPATH defined

Ken Englander — Wed, 29 Dec 2010 21:03:39 GMT

It could be that AIX has an LPATH used for similar purposes as we ported our application from AIX (and OpenVMS). I do not know the history but HP was helping us along the way.

It may be the -L is a better choice but it is too late now to change things - the use of LPATH is well embedded in our process.

I still would like to understand a bit more. Does the driver (compiler?) set up this variable during the boot or is it only set up on the fly when using the compiler.

I think the main reason we use it is to link with Oracle for our application.

Re: Where is env variable LPATH defined

Dennis Handly — Thu, 30 Dec 2010 09:31:19 GMT

>Does the driver set up this variable on the fly when using the compiler.

Only when linking. If you link with -v, the driver will print out the value if it sets it.

>I think the main reason we use it is to link with Oracle for our application.

If you are exporting LPATH, then you should know where you are doing it.

Re: Where is env variable LPATH defined

Ken Englander — Thu, 30 Dec 2010 15:27:04 GMT

> If you are exporting LPATH, then you should know where you are doing it

It took a little time to find out where we set it up and I confirmed that we do use it to link with Oracle. It is hard to know everything about what our company is doing! :)

Re: Where is env variable LPATH defined

Ken Englander — Thu, 30 Dec 2010 15:30:41 GMT

Thanks for the input!