The cflow utility analyzes a collection of source files
C programming language and outputs a graph charting
dependencies between various functions.
The program is able to produce two kind of graphs: direct
and reverse. Direct graph begins with the main function
main), and displays recursively all functions called by it.
In contrast, reverse graph is a set of subgraphs, charting for
each function its callers, in the reverse order. Due to their
tree-like appearance, graphs can also be called trees.
In addition to these two output modes, cflow is able to produce a cross-reference listing of all the symbols encountered in the input files.
The utility also provides a detailed control over symbols that will appear in its output, allowing to omit those that are of no interest to the user. The exact appearance of the output graphs is also configurable.