Open Source C Formats and Protocols

Browse free open source C Formats and Protocols and projects below. Use the toggles on the left to filter open source C Formats and Protocols by OS, license, language, programming language, and project status.

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  • 1
    The portable Universal Plug and Play (UPnP) SDK provides support for building UPnP-compliant control points, devices, and bridges on several operating systems. The main repository is at GitHub in https://github.com/pupnp/pupnp. This is just a clone repository for legacy reasons. Old SourceForge repo: git://pupnp.git.sourceforge.net/gitroot/pupnp/pupnp
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    Downloads: 3,901 This Week
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  • 2
    BibDesk

    BibDesk

    Bibliography manager for Mac OS X

    BibDesk is a graphical bibTeX bibliography manager for Mac OS X.
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    Downloads: 2,568 This Week
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  • 3
    Gwyddion

    Gwyddion

    Scanning probe microscopy data visualisation and analysis

    A data visualization and processing tool for scanning probe microscopy (SPM, i.e. AFM, STM, MFM, SNOM/NSOM, ...) and profilometry data, useful also for general image and 2D data analysis.
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    Downloads: 1,918 This Week
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  • 4
    QPDF

    QPDF

    PDF transformation/manipulation program + library

    QPDF is a C++ library and set of programs that inspect and manipulate the structure of PDF files. It can encrypt and linearize files, expose the internals of a PDF file, and do many other operations useful to end users and PDF developers.
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    Downloads: 985 This Week
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  • 5
    a POSIX-C implementation of the http://oauth.net/ protocol. libOauth provides functionality to encode URLs and sign HTTP request data according to the oAuth standard.
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    Downloads: 3,284 This Week
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  • 6
    jq

    jq

    Lightweight and flexible command-line JSON processor

    jq is like sed for JSON data - you can use it to slice, filter, map and transform structured data with the same ease that sed, awk, grep and friends let you play with text. jq is written in portable C, and it has zero runtime dependencies. You can download a single binary, scp it to a far away machine of the same type, and expect it to work. jq can mangle the data format that you have into the one that you want with very little effort, and the program to do so is often shorter and simpler than you'd expect. Data in jq is represented as streams of JSON values - every jq expression runs for each value in its input stream, and can produce any number of values to its output stream. jq filters run on a stream of JSON data. The input to jq is parsed as a sequence of whitespace-separated JSON values which are passed through the provided filter one at a time. The output(s) of the filter are written to standard out, again as a sequence of whitespace-separated JSON data.
    Downloads: 100 This Week
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  • 7
    pdfcrack is a command line, password recovery tool for PDF-files.
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    Downloads: 487 This Week
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  • 8
    gSOAP Toolkit

    gSOAP Toolkit

    Development toolkit for Web Services and XML data bindings for C & C++

    The gSOAP toolkit is an extensive suite of portable C and C++ software to develop XML Web services with powerful type-safe XML data bindings. Easy-to-use code-generator tools allow you to directly integrate XML data in C and C++. Serializes native application data in XML. Includes WSDL/XSD schema binding and auto-coding tools, stub/skeleton compiler, Web server integration with Apache module and IIS extension, high-performance XML processing with schema validation, fast MIME/MTOM streaming, SOAP and REST Web API development, WS-* protocols (WS-Security, WS-Policy, WS-ReliableMessaging, etc), XML-RPC and JSON. Licensed under GPLv2. Visit the developer center with guides, tutorials, and examples at www.genivia.com/dev.html The documentation of the toolkit, libraries, plugins and more is available at www.genivia.com/docs.html Commercial-use licenses and expert technical support services are available at competitive pricing levels, please visit www.genivia.com/products.html
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    Downloads: 451 This Week
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  • 9

    Expat XML Parser

    Fast XML parser library in C

    PLEASE NOTE that we are in the process of moving to GitHub: https://github.com/libexpat/libexpat This is James Clark's Expat XML parser library in C. It is a stream oriented parser that requires setting handlers to deal with the structure that the parser discovers in the document. PLEASE NOTE that we are in the process of moving to GitHub: https://github.com/libexpat/libexpat
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    Downloads: 396 This Week
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  • 10
    xrdp

    xrdp

    An open source RDP server

    xrdp provides a graphical login to remote machines using RDP (Microsoft Remote Desktop Protocol). xrdp accepts connections from a variety of RDP clients: FreeRDP, rdesktop, NeutrinoRDP and Microsoft Remote Desktop Client (for Windows, macOS, iOS and Android). As Windows-to-Windows Remote Desktop can, xrdp supports not only graphics remoting but also two-way clipboard transfer (text, bitmap, file), audio redirection, drive redirection (mount local client drives on a remote machine). Connect to a Linux desktop using RDP from anywhere (requires xorgxrdp Xorg module). Reconnect to an existing session. Session resizing (both on-connect and on-the-fly). RDP/VNC proxy (connect to another RDP/VNC server via xrdp). xrdp primarily targets GNU/Linux operating system. x86 (including x86-64) and ARM processors are most mature architecture to run xrdp on. Most Linux distributions should distribute the latest release of xrdp in their repository.
    Downloads: 59 This Week
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  • 11
    matio is an C library for reading and writing MATLAB MAT files.
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    Downloads: 285 This Week
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  • 12
    libmng -THE reference library for reading, displaying, writing and examining Multiple-Image Network Graphics. MNG is the animation extension to the popular PNG image-format.
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    Downloads: 1,079 This Week
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  • 13
    Biosignal Tools
    BioSig is a software library for processing of biomedical signals (EEG, ECG, etc.) with Matlab, Octave, C/C++ and Python. About 50 different data formats are supported.
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    Downloads: 167 This Week
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  • 14
    FLAC is a free lossless compressed audio format which supports streaming and archival. The FLAC project maintains the format and provides a reference encoder/decoder and input plugins for several popular audio players.
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    Downloads: 162 This Week
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  • 15
    Apache Guacamole

    Apache Guacamole

    HTML5 Clientless Remote Desktop

    Apache Guacamole is a clientless remote desktop gateway. It supports standard protocols like VNC, RDP, and SSH. We call it clientless because no plugins or client software are required. Thanks to HTML5, once Guacamole is installed on a server, all you need to access your desktops is a web browser.
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    Downloads: 129 This Week
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  • 16
    An ultra-lightweight, portable, single-file, simple-as-can-be ANSI-C compliant JSON parser, under MIT license. Moved to https://github.com/DaveGamble/cJSON
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    Downloads: 128 This Week
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  • 17
    The USB/IP Project
    The USB/IP Project aims to develop a general USB device sharing system over IP network. To share USB devices between computers with their full functionality, USB/IP encapsulates USB I/O requests into IP packets and transmits them between computers.
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    Downloads: 139 This Week
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  • 18
    Tidy

    Tidy

    The granddaddy of HTML tools, with support for modern standards

    Tidy is a console application for macOS, Linux, Windows, UNIX, and more. It corrects and cleans up HTML and XML documents by fixing markup errors and upgrading legacy code to modern standards. libtidy is a C static and dynamic library that developers can integrate into their applications in order to bring all of Tidy’s power to your favorite tools. libtidy is used today in desktop applications, web servers, and more. Tidy tidies HTML and XML. It can tidy your documents by itself, and developers can easily integrate its features into even more powerful tools. Thanks for the efforts of HTACG and prominent contributors, HTML Tidy has a whole new heartbeat and a whole new life.
    Downloads: 22 This Week
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  • 19
    MiKTeX

    MiKTeX

    the MiKTeX source code

    MiKTeX is a modern TeX distribution for Windows, Linux, and macOS. MiKTeX's integrated package manager installs missing components from the Internet if required. This allows you to keep your TeX installation as minimal as possible (“Just enough TeX”). MiKTeX is open source. You are welcome to redistribute MiKTeX under certain conditions.
    Downloads: 20 This Week
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  • 20
    Mozilla JPEG Encoder Project

    Mozilla JPEG Encoder Project

    Improved JPEG encoder

    MozJPEG improves JPEG compression efficiency achieving higher visual quality and smaller file sizes at the same time. It is compatible with the JPEG standard, and the vast majority of the world's deployed JPEG decoders. MozJPEG is compatible with the libjpeg API and ABI. It is intended to be a drop-in replacement for libjpeg. MozJPEG is a strict superset of libjpeg-turbo's functionality. All MozJPEG's improvements can be disabled at run time, and in that case it behaves exactly like libjpeg-turbo. MozJPEG is meant to be used as a library in graphics programs and image processing tools. We include a demo cjpeg command-line tool, but it's not intended for serious use. We encourage authors of graphics programs to use libjpeg's C API and link with MozJPEG library instead. Progressive encoding with "jpegrescan" optimization. It can be applied to any JPEG file (with jpegtran) to losslessly reduce file size.
    Downloads: 19 This Week
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  • 21
    gputils is a collection of tools for Microchip PIC microcontrollers. Its goal is to be fully compatible with Microchip's tools, MPASM, MPLINK, and MPLIB.
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    Downloads: 95 This Week
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  • 22
    OpenCTM
    OpenCTM is a file format, a software library and a tool set for compression of 3D triangle meshes. The geometry is compressed to a fraction of comparable file formats (3DS, STL, COLLADA...), and the format is accessible through a simple, portable API
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    Downloads: 354 This Week
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  • 23
    Systems Biology Markup Language (SBML)

    Systems Biology Markup Language (SBML)

    A file format for exchanging computational models in systems biology

    The Systems Biology Markup Language (SBML) is an XML-based description language for representing computational models in systems biology. Visit the project web site to learn more.
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    Downloads: 55 This Week
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  • 24
    MsQuic

    MsQuic

    Cross-platform, C implementation of the IETF QUIC protocol

    MsQuic is a Microsoft implementation of the IETF QUIC protocol. It is cross-platform, written in C and designed to be a general-purpose QUIC library. MsQuic also has C++ API wrapper classes and exposes interop layers for both Rust and C#. QUIC has many benefits when compared to existing "TLS over TCP" scenarios. MsQuic has several features that differentiate it from other QUIC implementations. Optimized for client and server. Optimized for maximal throughput and minimal latency. Asynchronous IO. Receive side scaling (RSS) support. UDP send and receive coalescing support. All packets are encrypted and handshake is authenticated with TLS 1.3. Parallel streams of (reliable and unreliable) application data. Exchange application data in the first round trip (0-RTT). Improved congestion control and loss recovery. Survives a change in the clients IP address or port. Stateless load balancing.
    Downloads: 12 This Week
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  • 25
    Libnodave is a library that provides the necessary functions to connect to and exchange data with Siemens S7 300/400 PLCs (200 family and S5 family now also supported). Can now also be used under Win32.
    Downloads: 49 This Week
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