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(textutils.info)tsort invocation

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`tsort': Topological sort
=========================

   `tsort' performs a topological sort on the given FILE, or standard
input if no input file is given or for a FILE of `-'.  Synopsis:

     tsort [OPTION] [FILE]

   `tsort' reads its input as pairs of strings, separated by blanks,
indicating a partial ordering.  The output is a total ordering that
corresponds to the given partial ordering.

   For example

     tsort <<EOF
     a b c
     d
     e f
     b c d e
     EOF

will produce the output

     a
     b
     c
     d
     e
     f

   `tsort' will detect cycles in the input and writes the first cycle
encountered to standard error.

   Note that for a given partial ordering, generally there is no unique
total ordering.

   The only options are `--help' and `--version'.  Note: Common
options.