Unable to build a shared library

I run R2011b on Mac OSX10.6.8. When I try the users' guide example of shared library compilation and execute the command:

>> mbuild matrixdriver.c -L. -lmatrix -I. -v

the build process terminates immediatly with no error messages, just:

----------------------------------------------------------------
-> mbuildopts.sh sourced from directory (DIR = $PREF_DIR)
   FILE = /Users/dan/.matlab/R2011b/mbuildopts.sh
----------------------------------------------------------------
-> TMW_ROOT = /Applications/MATLAB_R2011b.app
-> CC = gcc-4.2
-> CC flags:
         CFLAGS = -fno-common -no-cpp-precomp -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -mmacosx-version-min=10.5 -I/Applications/MATLAB_R2011b.app/extern/include -DUNIX -DX11
         CDEBUGFLAGS = -g
         COPTIMFLAGS = -O2 -DNDEBUG
         CLIBS = -L/Applications/MATLAB_R2011b.app/runtime/maci64 -lmwmclmcrrt
         arguments = 
-> LD = gcc-4.2
-> Link flags:
         LDFLAGS = -Wl,-twolevel_namespace -undefined error -arch x86_64 -Wl,-syslibroot,/Developer/SDKs/MacOSX10.6.sdk -mmacosx-version-min=10.5 -bind_at_load
         LDDEBUGFLAGS = -g
         LDOPTIMFLAGS = -O
         arguments = -L.
----------------------------------------------------------------
-> gcc-4.2 -c -I. -fno-common -no-cpp-precomp -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -mmacosx-version-min=10.5 -I/Applications/MATLAB_R2011b.app/extern/include -DUNIX -DX11 -O2 -DNDEBUG "matrixdriver.c"
-> gcc-4.2 -O -Wl,-twolevel_namespace -undefined error -arch x86_64 -Wl,-syslibroot,/Developer/SDKs/MacOSX10.6.sdk -mmacosx-version-min=10.5 -bind_at_load -framework CoreFoundation -L. -o matrixdriver.app/Contents/MacOS/matrixdriver matrixdriver.o -L/Applications/MATLAB_R2011b.app/runtime/maci64 -lmwmclmcrrt -lmatrix
----------------------------------------------------------------
The directory matrixdriver.app has been created and the files matrixdriver.app/Contents/MacOS/applauncher matrixdriver prelaunch 
are also created.
I have set correctly the DYLD_LYBRARY_PATH for MCR.
When I try to execute in the Terminal window the command:

> .../work/libexample/matrixdriver.app/Contents/MacOS/matrixdriver
I get the message:
dyld: Library not loaded: @loader_path/libmatrix.dylib
  Referenced from: .../work/libexample/matrixdriver.app/Contents/MacOS/matrixdriver
  Reason: no suitable image found. Did find:
/System/Library/Frameworks/JavaVM.framework/JavaVM/libmatrix.dylib: stat() failed with errno=20
Trace/BPT trap

apparently the DYLD lib has not been correctly linked.

Can you provide any suggestion? best regards

Answer 1

[Kaustubha Govind]

Are you running the example on this page? If yes, you should have also run the following command to generate libmatrix.dylib:

   mcc -B csharedlib:libmatrix addmatrix.m multiplymatrix.m 
eigmatrix.m -v

You probably need to add the directory containing this library also to DYLD_LYBRARY_PATH.

Answer 2

[Daniele Marini]

Indeed I have previously complide the library creating the files: libmatrix.c libmatrix.dylib libmatrix.exports libmatrix.h

then I run: mbuild matrixdriver.c -L. -lmatrix -I.

I open a Terminal and check the path:

DYLD_LIBRARY_PATH=/Applications/MATLAB/MATLAB_Compiler_Runtime/v716/runtime/maci64: /Applications/MATLAB/MATLAB_Compiler_Runtime/v716/sys/os/maci64: /Applications/MATLAB/MATLAB_Compiler_Runtime/v716/bin/maci64: /System/Library/Frameworks/JavaVM.framework/JavaVM: /System/Library/Frameworks/JavaVM.framework/Libraries XAPPLRESDIR=/Applications/MATLAB/MATLAB_Compiler_Runtime/v716/X11/app-defaults

and run the command:

my_work_directory/matrixdriver.app/Contents/MacOS/matrixdriver

getting the message:

dyld: Library not loaded: @loader_path/libmatrix.dylib Referenced from: /Users/dan/Documents/MATLAB/work/sharedlib/matrixdriver.app/Contents/MacOS/matrixdriver Reason: no suitable image found. Did find: /System/Library/Frameworks/JavaVM.framework/JavaVM/libmatrix.dylib: stat() failed with errno=20 Trace/BPT trap

any other suggestion? Daniele

Answer 3

[Daniele Marini]

Oops. I have added the path to the compiled shared library and now it works! many thanks Daniele