Open Source C Communications Software

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

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  • 1
    Zero Install
    Zero Install is a decentralised cross-distribution software installation system. Create one package that works everywhere! With dependency handling and automatic updates, full support for shared libraries, and integration with native package managers
    Leader badge
    Downloads: 2,488 This Week
    Last Update:
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  • 2
    fldigi

    fldigi

    Ham Radio Digital Modem Application

    Fldigi is a modem program for most of the digital modes used by radio amateurs today: CW, PSK, MFSK, RTTY, Hell, DominoEX, Olivia, and Throb are all supported. It can help calibrate a sound card to a time signal and do frequency measurement tests. NOTICE: You must proceed to the Files section to locate the correct fldigi, flrig etal download for your particular operating system. Do not blithely use the big green Download button! Use the "Files" menu item or the "Browse All Files" link.
    Leader badge
    Downloads: 2,468 This Week
    Last Update:
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  • 3
    Pidgin IM

    Pidgin IM

    A universal instant messaging (IM) program

    See https://pidgin.im/about/ for more information. Pidgin is an instant messaging program which lets you log in to accounts on multiple chat networks simultaneously. It runs on Windows, Linux, and other UNIX operating systems. Pidgin is compatible with the following chat networks out of the box: AIM, ICQ, Google Talk, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, MXit, Novell GroupWise Messenger, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr. It is written in C and makes heavy use of GLib and GTK+. Finch is a command line instant messaging program. It also lets you log in to accounts on multiple chat network simultaneously, and it is compatible with the same chat networks as Pidgin. It is written in C and makes heavy use of GLib and ncurses.
    Leader badge
    Downloads: 4,893 This Week
    Last Update:
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  • 4
    Gtk-Gnutella

    Gtk-Gnutella

    A GTK+ Gnutella client, optimized for speed and scalability

    A GTK+ Gnutella client, efficient, reliable and fast, written in C. It has been optimized for speed and scalability, with low-memory consumption. It is meant to be left running 24x7, using little CPU and only the configured bandwidth. It is possible to run gtk-gnutella without a GUI or using a shell interface.
    Downloads: 357 This Week
    Last Update:
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    Gpredict

    Gpredict

    Real time satellite tracking and orbit prediction

    Gpredict is a real-time satellite tracking and orbit prediction application. Gpredict can track an unlimited number of satellites and display the data in tables and various graphical view.
    Leader badge
    Downloads: 270 This Week
    Last Update:
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  • 6
    BlackBelt Privacy Tor/i2p+WASTE+VidVoIP

    BlackBelt Privacy Tor/i2p+WASTE+VidVoIP

    Browse on Tor/i2p, Anon p2p Chat / FileTx, Conf / Video VoIP

    Open Source - GPLv3 inc images. *** PLEASE NOTE: There are now 2 seperate versions here. *** One is Pre Firefox 57. The other is Post Firefox 57. *** For those providing mirrors, please enable your users to realize this. Vidalia Based, Tor as a Service Solution. MicroSip: enables FREE PC to PC video calling with no account sign-up and no middleman server. WASTE: enables FREE Conference VoIP, chat, file transfer and support. *** AI Powered *** Tor/i2p: enables safer browsing. Tor/i2p Profile: Browse over Tor/i2p on Firefox (Vanilla, ESR), Waterfox (Classic, New), Palemoon , LibreWolf and legacy CyberFox. As with all versions of Tor - do not rely on this for strong anonymity. A usability enhanced Privacy Pack. Use alongside Tor Browser Bundle. An installer, for : Vista 32/64, Win7 32/64, Win8 32/64, Win10 32/64, Win11, Linux (Wine)
    Downloads: 46 This Week
    Last Update:
    See Project
  • 7
    Protocol plugin for Office 365/Lync/OCS

    Protocol plugin for Office 365/Lync/OCS

    for Adium, Pidgin, Miranda and Telepathy IM Framework

    Please make sure to read this page: http://sourceforge.net/p/sipe/wiki/Frequently%20Asked%20Questions/ A third-party Pidgin/Adium/Miranda/Telepathy plugin for the extended version of SIP/SIMPLE used by various products: * Skype for Business * Microsoft Office 365 * Microsoft Business Productivity Online Suite (BPOS) * Microsoft Lync Server * Microsoft Office Communications Server (OCS 2007/2007 R2) * Microsoft Live Communications Server (LCS 2003/2005)
    Downloads: 28 This Week
    Last Update:
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  • 8
    RetroShare

    RetroShare

    [WARNING] Project has moved to http://github.com/Retroshare/Retroshare

    [IMPORTANT] Retroshare is now distributed on Github. Please go to http://retroshare.net to find the latest releases and sources. RetroShare is a cross-platform, secured and decentralized communication system. It lets you to securely chat, share photos, videos, and more with family and friends, using OpenPGP to authenticate peers and OpenSSL to encrypt all communication.
    Downloads: 16 This Week
    Last Update:
    See Project
  • 9
    emesene
    emesene is a platform independent instant messaging client for the Windows Live Messenger (tm) network. emesene is distributed free of charge under the GNU General Public License 2 or any later version.
    Downloads: 7 This Week
    Last Update:
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  • 10
    Repeater controller and EchoLink software for Linux including a GUI, Qtel - the Qt EchoLink client. The SvxLink project has now moved to GitHub. The new home page for the project is http://svxlink.org/ .
    Downloads: 13 This Week
    Last Update:
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  • 11
    Bot Sentry is a Pidgin (libpurple) plugin to prevent Instant Message (IM) spam. It allows you to ignore IMs unless the sender is in your Buddy List, the sender is in your Allow List, or the sender correctly answers a question you have predefined.
    Downloads: 8 This Week
    Last Update:
    See Project
  • 12
    Xdx DX Cluster client

    Xdx DX Cluster client

    DX Cluster client for radio amateurs

    A handy stand-alone GTK+ client for accessing your favorite DX Cluster or Reverse Beacon Net server via telnet over TCP/IP.
    Downloads: 18 This Week
    Last Update:
    See Project
  • 13
    MailCleaner

    MailCleaner

    Anti Spam SMTP Gateway

    MailCleaner Open Source Edition is now discontinued but will continue under the spamtagger project https://github.com/SpamTagger [antispam] MailCleaner is an anti-spam / anti-virus filter SMTP gateway with user and admin web interfaces, quarantine, multi-domains, multi-templates, multi-languages. Using Bayes, RBLs, Spamassassin, MailScanner, ClamAV. Based on Debian. Enterprise ready. MailCleaner is an anti spam gateway installed between your mail infrastructure and the Internet. It includes a complete GNU/Linux OS and a graphical web interface for user and administrative access. It comes in the form of virtual machine templates.. - fully compatible with any SMTP mail server (Exchange, Zimbra, O365,...)
    Downloads: 7 This Week
    Last Update:
    See Project
  • 14
    Mailman is the GNU mailing list manager. It provides standard list management features, integrated with a web interface. Please note: the subversion repository has been retired. Please see http://wiki.list.org/x/DgAJ for details.
    Downloads: 10 This Week
    Last Update:
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  • 15

    linSmith

    Smith chart intended for educational use

    A Smith charting program. You can enter either discrete components or transmission lines, see the results on screen and/or generate Postscript output. Component values can be changed numerically or using scrollbars.
    Downloads: 10 This Week
    Last Update:
    See Project
  • 16
    provides popups for pidgin via a libnotify interface
    Downloads: 8 This Week
    Last Update:
    See Project
  • 17

    Darkbot

    The IRC's Talking Robot

    [ Please read https://sourceforge.net/p/darkbot/news/2014/01/darkbots-revitalization/ ] Darkbot is a portable IRC chat robot written in the C language that can be taught responses to user inquiries, and even have conversations with them. Darkbot was originally created by Jason Hamilton as an aid for help channels on Intenet Relay Chat.
    Leader badge
    Downloads: 23 This Week
    Last Update:
    See Project
  • 18
    Kiax is a softphone (soft phone, VoIP client) with a simple and comfortable user interface for making VoIP calls to Asterisk PBX. It depends on the iaxclient library to use Asterisk's IAX2 protocol for easy call configuration and audio setup.
    Downloads: 5 This Week
    Last Update:
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  • 19
    QmailAdmin is a web interface for managing email addresses in virtual domains created by Vpopmail.
    Downloads: 4 This Week
    Last Update:
    See Project
  • 20

    MBSE BBS for Linux & Unix

    MBSE BBS is a full FTN-capable ANSI BBS and mailer package.

    MBSE BBS is a fully FTN-capable ANSI BBS package including a mailer (ifcico clone), BinkP daemon, mail tosser, TIC processor, filefind, and other utilities allowing access via modem and the Internet using telnet, ssh, http and ftp. Support is offered through the Fidonet MBSE echo and the Micronet MIN_BBS echo.
    Downloads: 5 This Week
    Last Update:
    See Project
  • 21
    XASTIR

    XASTIR

    Multiplatform Ham Radio APRS and Mapping Program

    NOTE: Code commits are FROZEN on SourceForge: New code is now at <http://github.com/Xastir/Xastir>. Real-time tracking & messaging of stations via radio/internet APRS data streams, w/125 map formats supported. Linux/FreeBSD/Solaris/MacOSX/Windows in any of 7 languages. Can also be used for mobile mapping w/GPS. MAILING LISTS ARE AT: PROJECT->WEB SITE.
    Downloads: 3 This Week
    Last Update:
    See Project
  • 22
    Graphical user interface for the Overnet and eDonkey2000 file-sharing command line clients. Runs on Linux, *BSD, MacOSX, and MS Windows.
    Downloads: 13 This Week
    Last Update:
    See Project
  • 23
    YAM - Yet Another Mailer

    YAM - Yet Another Mailer

    YAM - The E-mail client for Amiga computers

    YAM (short for Yet Another Mailer) is a commonly used MIME-compliant Internet mailer written for AmigaOS computers. It supports POP3, SMTP, TLSv1/SSLv3, multiple users, PGP, hierarchical folders, filters, a configurable GUI, an ARexx interface and more...
    Downloads: 12 This Week
    Last Update:
    See Project
  • 24
    Anope Services are built off of the original Epona code written by Lara which is built off of IRC Services. These services have advanced the original Epona code and include new features such as Modules, Mysql, and Defcon Mode.
    Downloads: 2 This Week
    Last Update:
    See Project
  • 25
    Yammy (Yahoo Messenger Archive Decoder) allows you to decode and view not only yours but, also other stored YM conversations. You don't even need a password!
    Downloads: 8 This Week
    Last Update:
    See Project
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