Directory Path listing of .sl in ldd

[Vibhor Kumar Agarwal]

Hello,

When doing ldd file.sl,
I am getting full path names of shared libs.
Eg.
a.sl -> /A/x.sl
b.sl -> /A/B/y.sl

Now the problem that I am facing is that:
There are 3 variable paths from where a .sl searches shared libs during runtime
SH_LIBPATH, LD_LIBRARY_PATH and Embedded Path (which contains the above eg. path )

Now during runtime it will search the shared libs in the following order
Embedded Path -> LD_LIBRARY_PATH -> SH_LIBPATH

So if i change my build location shared libs for some unit testing, then central testing will give abnormal results as it will start referencing these libs.

I have tried to disable path using
chatr +b disable
and
chatr +s disable

It gives me warning Embedded paths can't be disabled in an ELF file, and it disables the LD and SH ones.

So what should I do to overcome this.

[Ermin Borovac]

You can do

$ chatr +s enable file.sl

to change the search order to

LD_LIBRARY_PATH first
SHLIB_PATH second
embedded path third

Is that what you were looking for or am I a way off?

[ranganath ramachandra]

i am not sure i understand exactly what the problem is. if you do not want any embedded path (RPATH in elf lingo?), you can use the "+nodefaultrpath" linker option.

but i think the proper way to handle this is to set LD_LIBRARY_PATH appropriately in the different environments.

if you turn off all paths, where do you want the program to pick up libraries from ? the system libraries path (/usr/lib/...)?

[Vibhor Kumar Agarwal]

Phew,

All confused.

That day i had tried all the options including chatr +s enable file.sl and nothing worked.

Today by itself its showing the different order.

LD_LIBRARY_PATH -> SH_LIBPATH -> EmbeddedPath

+nodefaultrpath option worked out.
But what is it doing exactly, i think its not letting the .sl to search for that shared lib during runtime or something else.

[ranganath ramachandra]

+nodefaultrpath prevents the recording of link-time LPATH (typically /usr/lib/pa20_64:/opt/langtools/lib/pa20_64, set by compiler) as RPATH (embedded path).

[Vibhor Kumar Agarwal]

Thanks,

Can you help me in finding out what did i do wrong on the first occasion,
as it showed different order of all the 3 paths and i couldn't change them,

next time onwards its giving a different order. should i use +nodefaultrpath in my linking.
will there be any side effets?

[ranganath ramachandra]

"chatr +s enable +b enable " should set the order such that environment variable lookup is first in the order before embedded path. you can also pass '+s' and '+b' (in this order) to the linker (as -Wl,+s,+b through compiler). if you dont want any embedded path, you can use "+nodefaultrpath".