IRIX Base Documentation 2001 May/SGI IRIX Base Documentation 2001 May.iso/usr/share/catman/u_man/cat1/rcsintro.z/rcsintro

Text File | 2001-04-17 | 13.3 KB | 331 lines

RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))                                                        RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))



NNNNAAAAMMMMEEEE
     rcsintro - introduction to RCS commands

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     The Revision Control System (RCS) manages multiple revisions of files.
     RCS automates the storing, retrieval, logging, identification, and
     merging of revisions.  RCS is useful for text that is revised frequently,
     for example programs, documentation, graphics, papers, and form letters.

     The basic user interface is extremely simple.  The novice only needs to
     learn two commands:  cccciiii(1) and ccccoooo(1).  cccciiii, short for "check in", deposits
     the contents of a file into an archival file called an RCS file.  An RCS
     file contains all revisions of a particular file.  ccccoooo, short for "check
     out", retrieves revisions from an RCS file.

   FFFFuuuunnnnccccttttiiiioooonnnnssss ooooffff RRRRCCCCSSSS
     +o    Store and retrieve multiple revisions of text.  RCS saves all old
          revisions in a space efficient way.  Changes no longer destroy the
          original, because the previous revisions remain accessible.
          Revisions can be retrieved according to ranges of revision numbers,
          symbolic names, dates, authors, and states.

     +o    Maintain a complete history of changes.  RCS logs all changes
          automatically.  Besides the text of each revision, RCS stores the
          author, the date and time of check-in, and a log message summarizing
          the change.  The logging makes it easy to find out what happened to
          a module, without having to compare source listings or having to
          track down colleagues.

     +o    Resolve access conflicts.  When two or more programmers wish to
          modify the same revision, RCS alerts the programmers and prevents
          one modification from corrupting the other.

     +o    Maintain a tree of revisions.  RCS can maintain separate lines of
          development for each module.  It stores a tree structure that
          represents the ancestral relationships among revisions.

     +o    Merge revisions and resolve conflicts.  Two separate lines of
          development of a module can be coalesced by merging.  If the
          revisions to be merged affect the same sections of code, RCS alerts
          the user about the overlapping changes.

     +o    Control releases and configurations.  Revisions can be assigned
          symbolic names and marked as released, stable, experimental, etc.
          With these facilities, configurations of modules can be described
          simply and directly.

     +o    Automatically identify each revision with name, revision number,
          creation time, author, etc.  The identification is like a stamp that
          can be embedded at an appropriate place in the text of a revision.
          The identification makes it simple to determine which revisions of
          which modules make up a given configuration.



                                                                        PPPPaaaaggggeeee 1111






RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))                                                        RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))



     +o    Minimize secondary storage.  RCS needs little extra space for the
          revisions (only the differences).  If intermediate revisions are
          deleted, the corresponding deltas are compressed accordingly.

   GGGGeeeettttttttiiiinnnngggg SSSSttttaaaarrrrtttteeeedddd wwwwiiiitttthhhh RRRRCCCCSSSS
     Suppose you have a file ffff....cccc that you wish to put under control of RCS.
     If you have not already done so, make an RCS directory with the command

          mmmmkkkkddddiiiirrrr  RRRRCCCCSSSS

     Then invoke the check-in command

          cccciiii  ffff....cccc

     This command creates an RCS file in the RRRRCCCCSSSS directory, stores ffff....cccc into it
     as revision 1.1, and deletes ffff....cccc.  It also asks you for a description.
     The description should be a synopsis of the contents of the file.  All
     later check-in commands will ask you for a log entry, which should
     summarize the changes that you made.

     Files in the RCS directory are called RCS files; the others are called
     working files.  To get back the working file ffff....cccc in the previous example,
     use the check-out command

          ccccoooo  ffff....cccc

     This command extracts the latest revision from the RCS file and writes it
     into ffff....cccc.  If you want to edit ffff....cccc, you must lock it as you check it out
     with the command

          ccccoooo  ----llll  ffff....cccc

     You can now edit ffff....cccc.

     Suppose after some editing you want to know what changes that you have
     made.  The command

          rrrrccccssssddddiiiiffffffff  ffff....cccc

     tells you the difference between the most recently checked-in version and
     the working file.  You can check the file back in by invoking

          cccciiii  ffff....cccc

     This increments the revision number properly.

     If cccciiii complains with the message

          cccciiii eeeerrrrrrrroooorrrr:::: nnnnoooo lllloooocccckkkk sssseeeetttt bbbbyyyy _y_o_u_r _n_a_m_e






                                                                        PPPPaaaaggggeeee 2222






RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))                                                        RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))



     then you have tried to check in a file even though you did not lock it
     when you checked it out.  Of course, it is too late now to do the check-
     out with locking, because another check-out would overwrite your
     modifications.  Instead, invoke

          rrrrccccssss  ----llll  ffff....cccc

     This command will lock the latest revision for you, unless somebody else
     got ahead of you already.  In this case, you'll have to negotiate with
     that person.

     Locking assures that you, and only you, can check in the next update, and
     avoids nasty problems if several people work on the same file.  Even if a
     revision is locked, it can still be checked out for reading, compiling,
     etc.  All that locking prevents is a _c_h_e_c_k-_i_n by anybody but the locker.

     If your RCS file is private, i.e., if you are the only person who is
     going to deposit revisions into it, strict locking is not needed and you
     can turn it off.  If strict locking is turned off, the owner of the RCS
     file need not have a lock for check-in; all others still do.  Turning
     strict locking off and on is done with the commands

          rrrrccccssss  ----UUUU  ffff....cccc     and     rrrrccccssss  ----LLLL  ffff....cccc

     If you don't want to clutter your working directory with RCS files,
     create a subdirectory called RRRRCCCCSSSS in your working directory, and move all
     your RCS files there.  RCS commands will look first into that directory
     to find needed files.  All the commands discussed above will still work,
     without any modification.  (Actually, pairs of RCS and working files can
     be specified in three ways:  (a) both are given, (b) only the working
     file is given, (c) only the RCS file is given.  Both RCS and working
     files may have arbitrary path prefixes; RCS commands pair them up
     intelligently.)

     To avoid the deletion of the working file during check-in (in case you
     want to continue editing or compiling), invoke

          cccciiii  ----llll  ffff....cccc     or     cccciiii  ----uuuu  ffff....cccc

     These commands check in ffff....cccc as usual, but perform an implicit check-out.
     The first form also locks the checked in revision, the second one
     doesn't.  Thus, these options save you one check-out operation.  The
     first form is useful if you want to continue editing, the second one if
     you just want to read the file.  Both update the identification markers
     in your working file (see below).

     You can give cccciiii the number you want assigned to a checked in revision.
     Assume all your revisions were numbered 1.1, 1.2, 1.3, etc., and you
     would like to start release 2.  The command






                                                                        PPPPaaaaggggeeee 3333






RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))                                                        RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))



          cccciiii  ----rrrr2222  ffff....cccc     or     cccciiii  ----rrrr2222....1111  ffff....cccc

     assigns the number 2.1 to the new revision.  From then on, cccciiii will number
     the subsequent revisions with 2.2, 2.3, etc.  The corresponding ccccoooo
     commands

          ccccoooo  ----rrrr2222  ffff....cccc     and     ccccoooo  ----rrrr2222....1111  ffff....cccc

     retrieve the latest revision numbered 2._x and the revision 2.1,
     respectively.  ccccoooo without a revision number selects the latest revision
     on the _t_r_u_n_k, i.e. the highest revision with a number consisting of two
     fields.  Numbers with more than two fields are needed for branches.  For
     example, to start a branch at revision 1.3, invoke

          cccciiii  ----rrrr1111....3333....1111  ffff....cccc

     This command starts a branch numbered 1 at revision 1.3, and assigns the
     number 1.3.1.1 to the new revision.  For more information about branches,
     see rrrrccccssssffffiiiilllleeee(5).

   AAAAuuuuttttoooommmmaaaattttiiiicccc IIIIddddeeeennnnttttiiiiffffiiiiccccaaaattttiiiioooonnnn
     RCS can put special strings for identification into your source and
     object code.  To obtain such identification, place the marker

          $$$$IIIIdddd$$$$

     into your text, for instance inside a comment.  RCS will replace this
     marker with a string of the form

          $$$$IIIIdddd::::  _f_i_l_e_n_a_m_e  _r_e_v_i_s_i_o_n  _d_a_t_e  _t_i_m_e  _a_u_t_h_o_r  _s_t_a_t_e  $$$$

     With such a marker on the first page of each module, you can always see
     with which revision you are working.  RCS keeps the markers up to date
     automatically.  To propagate the markers into your object code, simply
     put them into literal character strings.  In C, this is done as follows:

          ssssttttaaaattttiiiicccc cccchhhhaaaarrrr rrrrccccssssiiiidddd[[[[]]]] ==== """"$$$$IIIIdddd$$$$"""";;;;

     The command iiiiddddeeeennnntttt extracts such markers from any file, even object code
     and dumps.  Thus, iiiiddddeeeennnntttt lets you find out which revisions of which
     modules were used in a given program.

     You may also find it useful to put the marker $$$$LLLLoooogggg$$$$ into your text,
     inside a comment.  This marker accumulates the log messages that are
     requested during check-in.  Thus, you can maintain the complete history
     of your file directly inside it.  There are several additional
     identification markers; see ccccoooo(1) for details.

IIIIDDDDEEEENNNNTTTTIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
     Author: Walter F. Tichy.
     Revision Number: 5.7; Release Date: 2000/10/27.
     Copyright c 1982, 1988, 1989 by Walter F. Tichy.



                                                                        PPPPaaaaggggeeee 4444






RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))                                                        RRRRCCCCSSSSIIIINNNNTTTTRRRROOOO((((1111))))



     Copyright c 1990, 1991, 1992, 1993 by Paul Eggert.

SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ci(1), co(1), ident(1), rcs(1), rcsdiff(1), rcsintro(1), rcsmerge(1),
     rlog(1), RCSsource(1)
     Walter F. Tichy, RCS--A System for Version Control, _S_o_f_t_w_a_r_e--_P_r_a_c_t_i_c_e &
     _E_x_p_e_r_i_e_n_c_e 11115555, 7 (July 1985), 637-654.
















































                                                                        PPPPaaaaggggeeee 5555