# Shared library not found

**URL:** <https://discourse.julialang.org/t/shared-library-not-found/3476>\
**Category:** General Usage\
**Tags:** ccall\
**Created:** [May 2, 2017, 9:50am UTC](https://discourse.julialang.org/t/shared-library-not-found/3476 "2017-05-02T09:50:53Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ettersi](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ettersi/32/6829_2.png) [@ettersi](https://discourse.julialang.org/u/ettersi)\
**Post date:** [May 2, 2017, 9:50am UTC](https://discourse.julialang.org/t/shared-library-not-found/3476/1 "2017-05-02T09:50:54Z")

</div>

I’m working on writing a julia interface to SuperLU ([https://github.com/dmbates/SuperLU.jl](https://github.com/dmbates/SuperLU.jl) is outdated). So I download and install SuperLU, and check that the shared library is properly installed:

```julia
~: ls /usr/local/lib/libsuperlu.so* -l
lrwxrwxrwx 1 root root 15 May 2 10:06 /usr/local/lib/libsuperlu.so -> libsuperlu.so.5
lrwxrwxrwx 1 root root 19 May 2 10:06 /usr/local/lib/libsuperlu.so.5 -> libsuperlu.so.5.2.1
-rwxr-xr-x 1 root root 724818 May 2 10:06 /usr/local/lib/libsuperlu.so.5.2.1

```

However, julia doesn’t find it:

```julia
julia> ptr = ccall(("intMalloc",:libsuperlu), Ptr{Cint},(Cint,),4)
ERROR: error compiling anonymous: could not load library "libsuperlu"
libsuperlu.so: cannot open shared object file: No such file or directory

julia> Base.Libdl.find_library("libsuperlu",String[])
""

```

Any idea what I’m doing wrong?

---

<div class="post-metadata">

**Author:** ![ettersi](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ettersi/32/6829_2.png) [@ettersi](https://discourse.julialang.org/u/ettersi)\
**Post date:** [May 2, 2017, 10:28am UTC](https://discourse.julialang.org/t/shared-library-not-found/3476/2 "2017-05-02T10:28:43Z")

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Found the issue, and it had nothing do with julia. Running `ldconfig` as suggested [here](https://codeyarns.com/2014/01/14/how-to-add-library-directory-to-ldconfig-cache/) solved the problem.