NAME    [Toc]    [Back]

     tsort -- topological sort of a directed graph

SYNOPSIS    [Toc]    [Back]

     tsort [-dlq] [file]

DESCRIPTION    [Toc]    [Back]

     The tsort utility takes a list of pairs of node names representing
     directed arcs in a graph and prints the nodes in topological order on
     standard output.  Input is taken from the named file, or from standard
     input if no file is given.

     Node names in the input are separated by white space and there must be an
     even number of nodes.

     Presence of a node in a graph can be represented by an arc from the node
     to itself.  This is useful when a node is not connected to any other
     nodes.

     If the graph contains a cycle (and therefore cannot be properly sorted),
     one of the arcs in the cycle is ignored and the sort continues.  Cycles
     are reported on standard error.

     The options are as follows:

     -d      Turn on debugging.

     -l      Search for and display the longest cycle.	Can take a very long
	     time.

     -q      Do not display informational messages about cycles.  This is primarily
 intended for building libraries, where optimal ordering is
	     not critical, and cycles occur often.

SEE ALSO    [Toc]    [Back]

     ar(1)

HISTORY    [Toc]    [Back]

     A tsort command appeared in Version 7 AT&T UNIX.  This tsort command and
     manual page are derived from sources contributed to Berkeley by Michael
     Rendell of Memorial University of Newfoundland.


FreeBSD 5.2.1			 April 1, 1994			 FreeBSD 5.2.1