Getting Started With The POCO C++ Libraries
AAAIntroduction

!!!Welcome

Thank you for downloading the POCO C++ Libraries and welcome to the growing community of POCO C++ Libraries
users. This document will help you in getting a smooth ride while installing and setting up the
POCO C++ Libraries and going the first steps with the software.


!!!Setting Up The POCO C++ Libraries

The POCO C++ Libraries are delivered in full source code only. Due to the
large number of possible build configurations, no binary releases are provided
from the project maintainers.
This means that you have to build the libraries and tools before you can use them the first time.

<*Note: There are binary releases available as installation packages for
various operating systems (e.g., Debian Linux, Ubuntu Linux, OpenBSD,
OpenWRT, etc.). However, these packages are not maintained by the core
team and may not always be up to date.*>

Up-to-date [[https://conan.io Conan]] packages are available via
[[https://bintray.com/pocoproject/conan/Poco%3Apocoproject Bintray]].


!!Source Code Distribution Format

The source code for the POCO C++ Libraries is delivered in a ZIP file
for Windows users and/or in a compressed TAR file (.tar.gz or .tar.bz2)
for Unix/Linux users. Both archives contain the same files, the only
difference is that all text files in the ZIP files have line endings
suitable for Windows (CR-LF), while the text files in the TAR file have
line endings suitable for Unix/Linux (LF only).
All libraries and tools follow a common convention for the directory
layout. This directory layout is shown below.

    build/                     the build system for Unix and additional utility scripts
        config/                build configurations for various Unix platforms
        rules/                 common build rules for all platforms
        scripts/               build and utility scripts
        vxconfig/              VxWorks build configurations

    cmake/                     Support files for CMake

    bin/                       all executables (dynamic link libraries on Windows)
    bin64/                     all 64-bit executables (and DLLs)

    doc/                       additional documentation

    lib/                       all libraries (import libraries on Windows)
    lib64/                     all 64-bit libraries

    CppUnit/                   project and make/build files for the CppUnit unit testing framework
        doc/                   additional documentation
        include/
            CppUnit/           header files for CppUnit
        src/                   source files for CppUnit
        WinTestRunner/         Windows GUI for CppUnit

    Foundation/                project and make/build files for the Foundation library
        include/
            Poco/              header files for the Foundation library
        src/                   source files for the Foundation library
        testsuite/             project and make/build files for the Foundation testsuite
            src/               source files for the Foundation testsuite
            bin/               test suite executables
        samples/               sample applications for the Foundation library

    XML/                       project and make/build files for the XML library
        include/
            Poco/
                XML/           header files for the core XML library
                SAX/           header files for SAX support
                DOM/           header files for DOM support
        src/                   source files for the XML library
        testsuite/             project and make/build files for the XML testsuite
            src/               source files for the XML testsuite
            bin/               test suite executables
        samples/               sample applications for the XML library

    Net/                       project and make/build files for the Net library
        include/
            Poco/
                Net/           header files for the Net library
        src/                   source files for the Net library
        testsuite/             project and make/build files for the Net testsuite
            src/               source files for the Net testsuite
            bin/               test suite executables
        samples/               sample applications for the Net library
----

Depending on what package you have downloaded (Basic or Complete
Edition), there may be other libraries as well (such as Data, Crypto,
NetSSL_OpenSSL and Zip).


!!External Dependencies

The following libraries require third-party software (header files and
libraries) being installed to build properly:

  - NetSSL_OpenSSL and Crypt require OpenSSL.
  - Data/ODBC requires ODBC
    (Microsoft ODBC on Windows, unixODBC or iODBC on Unix/Linux)
  - Data/MySQL requires the MySQL client.


!OpenSSL

<*Unix/Linux*>

Most Unix/Linux systems already have OpenSSL
preinstalled, or OpenSSL can be easily installed using the system’s
package management facility. For example, on Ubuntu (or other
Debian-based Linux distributions) you can type

    $ sudo apt-get install openssl libssl-dev
----

to install the necessary packages.
If your system does not have OpenSSL, please get it from
http://www.openssl.org/ or another source. You do not have to build
OpenSSL yourself -- a binary distribution is fine.

On macOS, it's recommended to install OpenSSL via Homebrew.

    $ brew install openssl
----


<*Windows*>

On Windows, there are three options:

  - Use POCO pre-built OpenSSL binaries (simplest and recommended)
  - Build OpenSSL using scripts from POCO distribution package
  - Use a third-party pre-built OpenSSL


<*POCO pre-built OpenSSL binaries*>

OpenSSL binaries (version 1.1.0) built with Visual Studio 2013 are available for
[[https://github.com/pocoproject/openssl/tree/master/build download]].

In case you are using pre-built binaries, please make sure to copy the
entire directory to <*C:\%POCO_BASE%\openssl\*>.

Or, %POCO_BASE%\openssl directory can be deleted (if existing) and POCO openssl
github repository cloned into it:

  $ cd %POCO_BASE%
  $ rmdir /s /q openssl
  $ git clone https://github.com/pocoproject/openssl

All libraries are located in their proper folders (eg. <*win64/bin/debug/*>),
and all are named accordingly (<*libcrypto[mt[d]]*> and <*libssl[mt[d]]*>).


<*Build OpenSSL using scripts from POCO distribution package*>

Alternatively, if you choose to build your own OpenSSL, POCO C++ Libraries
distribution package comes with scripts to build OpenSSL on Windows operating
system. This requires Windows PowerShell.

Usage:

    C:\%POCO_BASE%\openssl\build.ps1 [-openssl_release 1.0.0 | 1.1.0]
                                     [-vs_version 150 | 140 | 120 | 110 | 100 | 90]
                                     [-config     release | debug | both]
                                     [-platform   Win32 | x64]
                                     [-library    shared | static]
----

Example: Building OpenSSL 1.1.0, DLL release build for x64 with Visual Studio 2013:

    C:\%POCO_BASE%\openssl\build.ps1 -openssl_release 1.1.0 -vs_version 120 -config release -platform x64 -library shared
----

The above command will download all the necessary packages (perl, nasm, etc)
and build OpenSSL in <*C:\%POCO_BASE%\openssl\build*> directory; the built OpenSSL
binaries can be linked from EXEs and DLLs built with Visual Studio 2008 to 2017.

Pre-generated POCO Visual Studio projects are configured to use headers and
libraries from <*C:\%POCO_BASE%\openssl\build*> directory.

<*Use a third-party pre-built OpenSSL*>

Yet another way to install OpenSSL on Windows is to use a binary
(prebuild) release, for example the one from Shining Light
Productions that comes with a Windows installer
(http://www.slproweb.com/products/Win32OpenSSL.html).
Depending on where you have installed the OpenSSL libraries,
you might have to edit the build script (buildwin.cmd), or add the
necessary paths to the INCLUDE and LIB environment variables. You might also
have to edit the project settings if the names of the OpenSSL libraries
from your build differ from the names used in the project files.


!ODBC

The Data library requires ODBC support on your system if you want to
build the ODBC connector (which is the default). On Windows platforms,
ODBC should be readily available if you have the Windows SDK installed.
On Unix/Linux platforms, you can use [[http://www.iodbc.org/ iODBC]]
or [[http://www.unixodbc.org/ unixODBC]. On
Linux, use your distribution's package management system to install the
necessary libraries and header files. For example, on Ubuntu, type

    $ sudo apt-get install libiodbc2 libiodbc2-dev
----

to install the iODBC library and header files.

The Data/ODBC and Data/MySQL Makefiles will search for the ODBC and
MySQL headers and libraries in various places. Nevertheless, the
Makefiles may not be able to find the headers and libraries. In this
case, please edit the Makefile in Data/ODBC and/or Data/MySQL
accordingly.


!MySQL Client

The Data library requires the [[http://dev.mysql.com MySQL]] client
libraries and header files if you want to build the MySQL connector
(which is the default). On Windows platforms, use the MySQL client
installer to install the necessary files. On Unix/Linux platforms, use
the package management system of your choice to install the necessary
files. Alternatively, you can of course build MySQL yourself from
source.


!!Building using CMake

As an alternative to the platform specific Makefiles and Solutions, CMake can be used
to do build POCO C++ Libraries on any platform with any compiler. CMake is a meta build system and it 
generate native makefiles and workspaces that can be used in the compiler environment of 
your choice. For a quick overview see http://cgold.readthedocs.io/en/latest/overview/cmake-can.html

POCO C++ Libraries requires CMake 3.2 or higher. Static binaries for many platforms can be downloaded from http://www.cmake.org/

CMake supports out of source builds and this is the recommended way to build POCO C++ Libraries using CMake.

Assuming the POCO C++ Libraries source is located in /path/to/poco directory and you like to build POCO C++ Libraries just type the 
following commands (Command parameters are all the same on any platform).

    $ cmake -H/path/to/poco -B/path/to/poco-build
    $ cmake --build /path/to/poco-build --target all

This will build POCO C++ Libraries in a subdirectory <*poco-build*>. All files produced during build are located in this directory.

POCO C++ Libraries allows you to set some build time options. As an example: to disable the SevenZip support
type the following command:

    $ cmake -H/path/to/poco -B/path/to/poco-build -DENABLE_SEVENZIP=OFF
    $ cmake --build /path/to/poco-build --target all

Similar options are available for other components. To see and enable or disable available options execute following command:

    $ cmake-gui /path/to/poco-build

or for console only:

    $ ccmake /path/to/poco-build

POCO C++ Libraries options are prefixed with <*ENABLE_*>. (This will be changed in POCO 2.x.x to <*POCO_*>)

To use POCO C++ Libraries in your cmake project, add following line in your project for example to use crypto:

    find_package(Poco REQUIRED PocoCrypto)
    ....
    target_link_libraries(yourTargetName ... Poco::Crypto)

If you get an error like 'By not providing "FindPoco.cmake"', then you should set CMAKE_PREFIX_PATH to the installation directory of your POCO C++ Libraries. For example: 

    $ cmake -H/path/to/yourProject -B/path/to/yourProject-build -DCMAKE_PREFIX_PATH=/path/to/installationOf/poco
    
Some other Hints:

To use the compiler of your choice for example clang compiler, execute following cmake command:

    $ cmake -H/path/to/poco -B/path/to/poco-build -DCMAKE_C_COMPILER=/path/to/clang -DCMAKE_CXX_COMPILER=/path/to/clang++
    $ cmake --build /path/to/poco-build --target all
    
To cross compile POCO C++ Libraries for another architecture/device you should have a <*cmake toolchain file*> and execute following command:

    $ cmake -H/path/to/poco -B/path/to/poco-build -DCMAKE_TOOLCHAIN_FILE=/path/to/toolchainfile
    $ cmake --build /path/to/poco-build --target all    

See https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html for more information.

For a faster build, use ninja as build system. See https://ninja-build.org/
For example on Ubuntu execute following commands:

    $ sudo apt-get install ninja-build
    
This install <*ninja*> command. To use ninja-build execute following cmake commands:

    $ cmake -H/path/to/poco -B/path/to/poco-build -GNinja
    $ cmake --build /path/to/poco-build --target all

See https://cmake.org/cmake/help/latest/manual/cmake-generators.7.html for other generators.

To enable verbose output from Makefile builds, execute following cmake commands:

    $ cmake -H/path/to/poco -B/path/to/poco-build -DCMAKE_VERBOSE_MAKEFILE=ON
    $ cmake --build /path/to/poco-build --target all


Some more infos about cmake see:

$ cmake --help-full
https://cmake.org/cmake/help/latest/
http://cgold.readthedocs.io/en/latest/index.html
    

!!Building On Windows

Microsoft Visual Studio 2008 or newer is required to build the
POCO C++ Libraries on Windows platforms.
Solution and project files for all versions are included.
64-bit (x64) builds are supported as well.
You can either build from within Visual Studio (<*Build->Batch
Build->Select All;Rebuild*>) or from the command line. To build from the
command line, start the Visual Studio 2008 (or 2010, 2013, etc.) Command
Prompt and go (<[cd]>) to the directory where you have extracted the POCO
C++ Libraries sources. Then, simply start the <*buildwin.cmd*> script and
pass as argument the version of visual studio (90, 100, 110, ... 150). You
can customize what is being built by <*buildwin.cmd*> by passing appropriate
command line arguments to it. Call <*buildwin.cmd*> without arguments to see
what is available. Build environment is set up by the buildwin.cmd; to avoid
build problems, it is recommended to start the build in a clean command
prompt console, i.e. not in the one provided by Visual Studio for 32/64-bit
builds (although those will work fine if used appropriately for the right
32/64-bit build type).

To disable certain components (e.g., NetSSL_OpenSSL or Data/MySQL) from
the build, edit the text file named <*components*> in the distribution
root directory and remove or comment the respective lines.

Certain libraries, like NetSSL_OpenSSL, Crypto or Data/MySQL have
dependencies to other libraries. Since the build script does not know where to
find the necessary header files and import libraries, you have to either add
the header file paths to the <[INCLUDE]> environment variable and the
library path to the <[LIB]> environment variable, or you'll have to edit the
buildwin.cmd script, where these environment variables can be set as
well.

In order to run the test suite and the samples, the top-most bin
directory containing the resulting shared libraries must be in the PATH
environment variable.


!!Building On Unix/Linux/macOS

For building on Unix platforms, the POCO C++ Libraries come with their
own build system. The build system is based on GNU Make 3.80 (or newer),
with the help from a few shell scripts. If you do not have GNU Make 3.80
(or newer) installed on your machine, you will need to download it from
http://directory.fsf.org/devel/build/make.html and
build and install it prior to building the POCO C++ Libraries.

You can check the version of GNU Make installed on your system with

    $ gmake --version
----

or

    $ make --version
----

Once you have GNU Make up and running, the rest is quite simple.
To extract the sources and build all libraries, testsuites and samples, simply

    $ gunzip poco-X.Y.tar.gz
    $ tar -xf poco-X.Y.tar
    $ cd poco-X.Y
    $ ./configure
    $ gmake -s
----

For help, either invoke

    $ ./configure --help
----

Alternatively, you can read the configure script source for a list of possible options.
For starters, we recommend <[--no-tests]> and <[--no-samples]>, to reduce build times.
On a multicore or multiprocessor machine, use parallel makes to speed up
the build (<[make -j4]>).

Once you have successfully built POCO, you can install it
to <*/usr/local*> (or another directory specified as parameter
to configure <[--prefix=<path>]>):

    $ sudo gmake -s install
----

You can omit certain components from the build. For example, you might
want to omit Data/ODBC or Data/MySQL if you do not have the corresponding
third-party libraries (iodbc or unixodbc, mysqlclient) installed
on your system. To do this, use the <[--omit]> argument to configure:

    $ ./configure --omit=Data/ODBC,Data/MySQL
----

<*IMPORTANT: Make sure that the path to the build directory does not
contain symbolic links. Furthermore, on macOS (or other systems
with case insensitive filesystems), make sure that the characters in
the path have the correct case. Otherwise you'll get an error saying
"Current working directory not under $PROJECT_BASE.".*>


!!Building On QNX Neutrino

For QNX Neutrino, the Unix build system (see the instructions above) is used.
You can use the build system to cross-compile for a target platform on a
Solaris or Linux host. Unfortunately, the Cygwin-based Windows host
environment has some major quirks that prevent the build system from
working there. You can also use the build system on a self-hosted QNX
system. The default build configuration for QNX (found in
build/config/QNX) is for a self-hosted x86 platform. To specify another
target, edit the CCVER setting in the build configuration file. For
example, to compile for a PowerPC target, specify
CCVER=3.3.1,gcc_ntoppcbe.

Service Pack 1 for QNX Neutrino 6.3 must be installed, otherwise compiling the
Foundation library will fail due to a problem with the <*<list>*> header in the
default (Dinkumware) C++ standard library.

When building on QNX, you might want to disable NetSSL_OpenSSL, Crypto and
some Data connectors, unless you have the necessary third party components
available:

    $ ./configure --omit=NetSSL_OpenSSL,Crypto,Data/ODBC,Data/MySQL
----

!!!Tutorials And Sample Code

Introductory documentation consisting of various documents and tutorials
in the form of slide decks can be found at the
[[http://pocoproject.org/documentation/ POCO C++ Libraries Documentation]] page.

Sample applications demonstrating the various features of the POCO C++
Libraries are delivered with the source code. Every library's source
code directory
has a <*samples*> directory containing various sample applications.

When building the sample applications on platforms using the gmake-based
build system, please make sure that the environment variable
<[POCO_BASE]> contains
the path to the POCO C++ Libraries source tree root directory.


!!!Creating Your Own POCO-based Applications

The best way to create your first POCO-based application is by copying
one of the sample projects and making the desired changes. Examine the
project files and Makefiles to see what compiler options must be set for
your specific platform.