You need the following C/C++ libraries to build flowWorkspace from source (using Rtools for windows users).
 -- libxml2

 
 Linux users

 =============

 These libraries are installed in non-standard locations, please pass their 'prefix' to the configure script. e.g.

 R CMD INSTALL flowWorkspace/ --configure-args='--with-xml=/home/yourname/xml_dir'

 
 Also make sure these libraries can be found by R at run-time by adding them to LD_LIBRARY_PATH environment variable. e.g.

  export LD_LIBRARY_PATH=/home/yourname/xml_dir:$LD_LIBRARY_PATH

  
 Add this to your `~/.profile` file can avoid doing so next time.
  

 Windows users
 =============

 
 To install libxml2:
 
 1. Download the pre-built binary from http://rglab.github.io/binaries/
 
 2. unzip it (e.g. to c:\libxml2)
 and you should see the directory structure like below in both i386 and x64 folder
    |-include
    |---libxml2
    |-----libxml (all *.h are here)
    |-lib (we should have static libary libxml2.a here)
    
 3. set up the environment variable LIB_XML2 in order for flowWorkspace to find its library files and header files.  
 You can do this by:
  * right click "Computer" and select "Properties"
  * click "Advanced system settings" and select "Advanced" tab
  * click the "Environment Variables"  button and bring up the dialog box
  * click the "New" button and enter "LIB_XML2" in the "Variable name" field, and /path/to/your/libxml2 (e.g. c:/libxml2) in the "Variable value" field. 
   Remember to use "/" instead of "\" as the directory delimiter.
 
 You can download Rtools at http://www.murdoch-sutherland.com/Rtools/ which provides the resources for building R and R packages. You should add to the Path variable the paths to the various components of Rtools. Please read the "Windows Toolset" appendix at http://cran.r-project.org/doc/manuals/R-admin.html#The-Windows-toolset for more details.