acyclic - make directed graph acyclic

       Stephen C. North <north@research.att.com>
       Emden R. Gansner <erg@research.att.com>

       If the graph is strict and there is a cycle of length 2, the attributes of the reversed edge are lost.

       Some  edge  attributes are non-symmetric, referring to either the head or tail node. At present, there is
       no mechanism or convention for correctly switching or renaming these.

acyclic  is a filter that takes a directed graph as input and outputs a copy of the graph with sufficient
       edges reversed to make the graph acyclic. The reversed  edge  inherits  all  of  the  attributes  of  the
       original  edge.  The  optional  file  argument specifies where the input graph is stored; by default, the
       program reads from stdin.

       acyclic - make directed graph acyclic

       The following options are supported:

       -n     No output is produced, though the return value will indicate whether the graph is acyclic or not.

       -v     Print information about whether the file is acyclic, has a cycle or is undirected.

       -ooutfile
              causes the output to be written to the specified file; by default, output is written to stdout.

       -?     option causes the program to print usage information.

acyclic returns 0 if the graph is acyclic; 1 if the graph has a cycle; 2 if the graph is undirected;  and
       255 if there are any errors.

gc(1), dot(1), gvpr(1), gvcolor(1), ccomps(1), sccmap(1), tred(1), libgraph(3)

                                                  21 March 2001                                       ACYCLIC(1)

acyclic [ -nv?  ] [ -ooutfile ] [ file ]