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Version: Version 1.7

Get started with C

This guide walks you through the steps to use a sample project, and then explains how to integrate the Pdftools SDK into your application with the C programming language.

Getting started with a sample project

Learn how to use the Pdftools SDK using a C sample project and convert a PDF file to an image.


This sample project uses GCC toolset 4.8+ and CMake version 3.16 or higher.

Compile and run the sample

  1. Download a sample project, and then unzip the file.

  2. Navigate to the root directory of the unzipped sample project, and then run:

    cmake .
  3. Build the sample:

    cmake --build .
  4. Run the compiled sample application. Provide inputPath for the input PDF file and outputPath path for the output image file:

    ./pdftoolspdf2imgsimple <inputPath> <outputPath>

    For example, to render the sample PDF file PdfPrimerWhitePaper.pdf to a multi-page TIFF image format, run:

    ./pdftoolspdf2imgsimple PdfPrimerWhitePaper.pdf PdfPrimerWhitePaper.tiff

You can apply a similar procedure as described in this tutorial for other code samples. For more information, see Code samples page.

Integrate the SDK into your application

Integrate and initialize the Pdftools SDK into your application by following the instructions in the next sections.

Add the SDK to your project

  1. Click the download link to get the latest version of the Pdftools SDK for C in a zip archive.

    Optional: For older Linux distributions running glibc 2.12+, download the SDK from a separate download.

  2. Unzip the file on your machine into a local directory recommended for your operating system. For example:

    C:\Program Files\PDF Tools AG\

    Included subdirectories are:

    ~Containts important information in the file.
    libRuntime executable binaries and runtime import libraries:
    win-x86\PdfToolsSdk.dll and win-x86\PdfToolsSdk.lib for 32-bit Windows
    win-x64\PdfToolsSdk.dll and win-x64\PdfToolsSdk.lib for 64-bit Windows
    includeHeader files to include in your C or C++ project. The main header PdfTools.h includes all the other headers.
  3. Optional: The native libraries must be available in your compiler's library path. This step is only required if your build process doesn't resolve it automatically:

    Add the lib\win-x64 or lib\win-x86 subdirectory to the %PATH% environment variable.

Initialize the SDK

Initialize the Pdftools SDK with your license key. Substitute the <PDFSDK,V1,include-your-key-here> in the following function with the value of your license key:

// Initialize library

// Optional: Without a license key the Pdftools SDK returns watermarked results.
// Initialize the Pdftools SDK with a license key to remove the watermark.
// The Pdftools SDK returns an error if you use an invalid license key.
GOTO_CLEANUP_IF_FALSE_PRINT_ERROR(PdfTools_Sdk_Initialize(_T("$<PDFSDK,V1,include-your-key-here>$"), NULL), _T("Failed to set the license key. %s (ErrorCode: 0x%08x).\n"), szErrorBuff, PdfTools_GetLastError());

Without a valid license key the output files are watermarked. Get in touch with the Pdftools sales team through the Contact page to get a full license.

Uninitialize the SDK

After processing files with the Pdftools SDK, call the Uninitialize function to unload the library correctly:

// Uninitialize library

Implement your use case

  • Find more use cases and sample projects at the Code samples page.
  • For more technical information about the Pdftools SDK for C, consult the C technical notes.