cp -t Unix 5th Edition

While reading this marvelous retrospective, 

A Research UNIX Reader:
Annotated Excerpts from the Programmer’s Manual,
1971-1986
M. Douglas McIlroy

I came upon this passage:


CP (v1 page 17, v5 page 18)
     The war-horse utility cp and its close relative mv originally worked on lists of pairs. Such lists, howev er, could not be generated by the shell’s * convention. All too often mistyped lists clobbered precious files. Consequently both utilities were promptly cut back to handle just one from-to pair (v2). At the same time mv was generalized to move files to a named
 directory. Strangely cp picked up only a BUG note suggesting the feature. By the time of v3 both had converged to their present forms,  although an unexplained option -t intruded briefly in v5.  What seems natural in hindsight was not clear cut at the time: the final conventions arose only after long discussions about how properly to handle file permissions and multiple files. In fact the discussion is not yet closed. Whether and how to recurse on directories is still debated: v7, v8, and v9 each offered a different way to do it.


Ever the "Human manual page", I was quite curious what had "cp -t" done.  So off to the Version 5 Unix manual.



Comments