32v 1m tsort
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TSORT(1) UNIX Programmer's Manual TSORT(1)
tsort - topological sort
tsort [ file ]
_T_s_o_r_t produces on the standard output a totally ordered list of items consistent with a partial ordering of items men- tioned in the input _f_i_l_e. If no _f_i_l_e is specified, the standard input is understood.
The input consists of pairs of items (nonempty strings) separated by blanks. Pairs of different items indicate ord- ering. Pairs of identical items indicate presence, but not ordering.
Odd data: there is an odd number of fields in the input file.
Uses a quadratic algorithm; not worth fixing for the typical use of ordering a library archive file.