3. Windows

The easiest way to install YAZ on Windows is by downloading an installer from Index Data's Windows support area . The installer comes with source too - in case you wish to compile YAZ with different compiler options, etc.

3.1. Compiling from Source on Windows

YAZ is shipped with "makefiles" for the NMAKE tool that comes with Microsoft Visual Studio. It has been tested with Microsoft Visual Studio 2017 and 2019.

Start a command prompt and switch the sub directory WIN where the file makefile is located. Customize the installation by editing the makefile file (for example by using notepad). The following summarizes the most important settings in that file:


If set to 1, the software is compiled with debugging libraries (code generation is multi-threaded debug DLL). If set to 0, the software is compiled with release libraries (code generation is multi-threaded DLL).


If HAVE_TCL is set to 1, nmake will use the ASN.1 compiler (Tcl based). You must set TCL to the full path of the Tcl interpreter. A Windows version of Tcl is part of Git for Windows.

If you do not have Tcl installed, set HAVE_TCL to 0.


If GNU Bison is present, you might set HAVE_BISON to 1 and specify the Bison executable in BISON. Bison is only required if you use the Git version of YAZ or if you modify the grammar for CQL (cql.y).

A Windows version of GNU Bison can be fetched from here: Index Data's Windows support area .


If HAVE_ICONV is set to 1, YAZ is compiled with iconv support. In this configuration, set ICONV_DIR to the iconv source directory.


If HAVE_LIBXML2 is set to 1, YAZ is compiled with SRU support. In this configuration, set LIBXML2_DIR to the libxml2 source directory.

You can get pre-compiled Libxml2+Libxslt DLLs and headers from here. Should you with to compile those libraries yourself, refer to to Section 3.3, “Compiling Libxml2 and Libxslt on windows”


If HAVE_LIBXSLT is set to 1, YAZ is compiled with XSLT support. In this configuration, set LIBXSLT_DIR to the libxslt source directory.


libxslt depends on libxml2.


If HAVE_ICU is set to 1, YAZ is compiled with ICU support. In this configuration, set ICU_DIR to the ICU source directory.

Pre-compiled ICU libraries for various versions of Visual Studio can be found here or from Index Data's Windows support site.

When satisfied with the settings in the makefile, type



If the nmake command is not found on your system you probably haven't defined the environment variables required to use that tool. To fix that, find and run the batch file vcvarsall.bat. You need to run it from within the command prompt or set the environment variables "globally"; otherwise it doesn't work.

If you wish to recompile YAZ - for example if you modify settings in the makefile you can delete object files, etc by running.

      nmake clean

The following files are generated upon successful compilation:

bin/yaz5.dll / bin/yaz5d.dll

YAZ Release/Debug DLL.

lib/yaz5.lib / lib/yaz5d.lib

Import library for yaz5.dll / yaz5d.dll.

bin/yaz_cond5.dll / bin/yaz_cond5d.dll

Release/Debug DLL for condition variable utilities (condvar.c).

lib/yaz_cond5.lib / lib/yaz_cond5d.lib

Import library for yaz_cond5.dll / yaz_cond5d.dll.

bin/yaz_icu5.dll / bin/yaz_icu5d.dll

Release/Debug DLL for the ICU wrapper utility. Only build if HAVE_ICU is 1.

lib/yaz_icu5.lib / lib/yaz_icu5d.lib

Import library for yaz_icu5.dll / yaz_icu5d.dll.


Z39.50 multi-threaded test/example server. It's a WIN32 console application.


YAZ Z39.50 client application. It's a WIN32 console application. See chapter YAZ client for more information.


This program exposes the ICU wrapper library if that is enabled for YAZ. Only if ICU is available this program is built.


Simple console application implemented on top of the ZOOM functions. The application is a command line shell that allows you to enter simple commands to perform ZOOM operations.

bin/zoomtst1.exe, bin/zoomtst2.exe, ..

Several small applications that demonstrate the ZOOM API.

3.2. How to make apps using YAZ on Windows

This section will go though the process of linking your Windows applications with YAZ.

Some people are confused by the fact that we use the nmake tool to build YAZ. They think they have to do that too - in order to make their Windows applications work with YAZ. The good news is that you don't have to. You can use the integrated environment of Visual Studio if desired for your own application.

When setting up a project or Makefile you have to set the following:

include path

Set it to the include directory of YAZ.

import library yaz5.lib

You must link with this library. It's located in the sub directory lib of YAZ. If you want to link with the debug version of YAZ, you must link against yaz5d.lib instead.

dynamic link library yaz5.dll

This DLL must be in your execution path when you invoke your application. Specifically, you should distribute this DLL with your application.

3.3. Compiling Libxml2 and Libxslt on windows

Download libxml2 and Libxslt source and unpack it. In the example below we install Libxml2 2.9.2 and Libxslt 1.1.28 for 32-bit, so we use the destination directories libxml2.2.9.2.win32 and libxslt-1.1.28.win32 to reflect both version and architecture.

      cd win32
      cscript configure.js prefix=c:\libxml2-2.9.2.win32 iconv=no
      nmake install


There's an error in configure.js for Libxml2 2.9.2. Line 17 should be assigned to configure.ac rather than configure.in.

For Libxslt it is similar. We must ensure that compilation of Libxslt links against the already installed libxml2.

      cd win32
      cscript configure.js prefix=c:\libxslt-1.1.28.win32 iconv=no \
          lib=c:\libxml2-2.9.2.win32\lib \
      nmake install