GNU cflow

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Table of Contents

Introduction to cflow

GNU cflow analyzes a collection of C source files and prints a graph, charting control flow within the program.

GNU cflow is able to produce both direct and inverted flowgraphs for C sources. Optionally a cross-reference listing can be generated. Two output formats are implemented: POSIX and GNU (extended).

Input files can optionally be preprocessed before analyzing.

The package also provides Emacs major mode for examining the produced flowcharts in Emacs.

A sample of a direct flowchart is available online.

News About the Project

The version 1.6 of GNU cflow was released on February 23, 2019.

Visit the project page in Savannah for the information about development status and recent news.

Downloading cflow

Stable releases of GNU cflow are available for download from FTP archives on and from various mirrors worldwide. Please choose the location closer to you.

For the information about alpha releases, patches etc., please see the project's home page.


Complete documentation in TeXinfo format is included in the distribution. An online manual is available.

Mailing Lists

Send your bug reports, requests for help, suggestions, etc. to address bug-cflow at gnu dot org.

The project maintainer distributes via this list patches, announces and progress reports regarding GNU cflow. The list is moderated and low-traffic, no spam gets through to it, so you may wish to be subscribed.

Visit bug-cflow page to subscribe to the list.


GNU cflow is being maintained by Sergey Poznyakoff.

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