paper.ps

早期freebsd实现

-.25 F 1.53(are tool that assists with that task.)-.1 F 1.353(RCS manages re)
111 324 R 1.353(visions of te)-.25 F 1.354
(xt documents, in particular source programs, documentation, and)-.15 F .989
(test data.)111 336 R .989(It automates the storing, retrie)5.989 F -.25(va)
-.25 G .988(l, logging and identi\214cation of re).25 F .988
(visions, and it pro-)-.25 F .964
(vides selection mechanisms for composing con\214gurations.)111 348 R .964
(This paper introduces basic v)5.964 F(ersion)-.15 E .369
(control concepts and discusses the practice of v)111 360 R .369
(ersion control using RCS.)-.15 F -.15(Fo)5.369 G 2.869(rc).15 G .369
(onserving space,)433.981 360 R .705(RCS stores deltas, i.e., dif)111 372 R
.705(ferences between successi)-.25 F 1.006 -.15(ve r)-.25 H -.25(ev).15 G
3.206(isions. Se).25 F -.15(ve)-.25 G .706(ral delta storage methods).15 F .297
(are discussed.)111 384 R .297(Usage statistics sho)5.297 F 2.797(wt)-.25 G
.297(hat RCS')263.605 384 R 2.796(sd)-.55 G .296
(elta storage method is space and time ef)311.988 384 R(\214cient.)-.25 E
(The paper concludes with a detailed surv)111 396 Q .3 -.15(ey o)-.15 H 2.5(fv)
.15 G(ersion control tools.)302.17 396 Q/F3 10/Times-Bold@0 SF -.25(Ke)111 420
S(yw).25 E(ords)-.1 E F0 2.5(:c)C
(on\214guration management, history management, v)163.7 420 Q
(ersion control, re)-.15 E(visions, deltas.)-.25 E(1991/01/03)72 468 Q EP
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/F0 10/Times-Roman@0 SF(RCS \212 A System for V)72 48 Q(ersion Control)-1.11 E
(PSD:13-1)500.55 48 Q/F1 12/Times-Bold@0 SF(RCS\212A System f)212.538 123 Q
(or V)-.3 E(ersion Contr)-1.2 E(ol)-.216 E/F2 10/Times-Italic@0 SF -.92(Wa)
275.96 162 S(lter F).92 E 2.5(.T)-1.35 G(ic)319.53 162 Q(hy)-.15 E F0
(Department of Computer Sciences)236.985 180 Q(Purdue Uni)269.675 192 Q -.15
(ve)-.25 G(rsity).15 E -.8(We)244.8 204 S(st Laf).8 E(ayette, Indiana 47907)-.1
E/F3 10/Times-Bold@0 SF 2.5(1. Intr)72 267.6 R(oduction)-.18 E F0 -1.11(Ve)97
289.2 S .847(rsion control is the task of k)1.11 F .847(eeping softw)-.1 F .847
(are systems consisting of man)-.1 F 3.348(yv)-.15 G .848
(ersions and con\214gurations well)412.746 289.2 R(or)72 307.2 Q -.05(ga)-.18 G
2.5(nized. The).05 F(Re)2.5 E(vision Control System \(RCS\) is a set of UNIX c\
ommands that assist with that task.)-.25 E .29
(RCS' primary function is to manage)97 328.8 R F2 -1.91 -.37(re v)2.79 H .29
(ision gr).37 F(oups)-.45 E F0 5.29(.A)C(re)326.129 328.8 Q .289
(vision group is a set of te)-.25 F .289(xt documents, called)-.15 F F2 -1.91
-.37(re v)2.789 H(i-).37 E(sions)72 346.8 Q F0 2.921(,t)C .421(hat e)100.761
346.8 R -.2(vo)-.25 G(lv).2 E .421(ed from each other)-.15 F 5.421(.A)-.55 G
(ne)231.548 346.8 Q 2.922(wr)-.25 G -.25(ev)254.21 346.8 S .422
(ision is created by manually editing an e).25 F .422(xisting one.)-.15 F .422
(RCS or)5.422 F -.05(ga)-.18 G(nizes).05 E .145(the re)72 364.8 R .145
(visions into an ancestral tree.)-.25 F .144(The initial re)5.145 F .144
(vision is the root of the tree, and the tree edges indicate from which)-.25 F
(re)72 382.8 Q .859(vision a gi)-.25 F -.15(ve)-.25 G 3.359(no).15 G .859(ne e)
145.307 382.8 R -.2(vo)-.25 G(lv).2 E 3.359(ed. Besides)-.15 F .859
(managing indi)3.359 F .859(vidual re)-.25 F .859(vision groups, RCS pro)-.25 F
.86(vides \215e)-.15 F .86(xible selection func-)-.15 F .489
(tions for composing con\214gurations.)72 400.8 R .489
(RCS may be combined with MAKE)5.489 F(1)368.341 395.8 Q 2.989(,r)373.341 400.8
S .489(esulting in a po)382.16 400.8 R .488(werful package for v)-.25 F(er)-.15
E(-)-.2 E(sion control.)72 418.8 Q .628(RCS also of)97 440.4 R .628(fers f)-.25
F .628(acilities for mer)-.1 F .629
(ging updates with customer modi\214cations, for distrib)-.18 F .629
(uted softw)-.2 F .629(are de)-.1 F -.15(ve)-.25 G(lop-).15 E .77
(ment, and for automatic identi\214cation.)72 458.4 R .77
(Identi\214cation is the `stamping' of re)5.77 F .77
(visions and con\214gurations with unique)-.25 F(mark)72 476.4 Q 2.546
(ers. These)-.1 F(mark)2.546 E .046
(ers are akin to serial numbers, telling softw)-.1 F .046
(are maintainers unambiguously which con\214guration)-.1 F(is before them.)72
494.4 Q 1.653(RCS is designed for both production and e)97 516 R 1.652
(xperimental en)-.15 F 4.152(vironments. In)-.4 F 1.652(production en)4.152 F
1.652(vironments, access)-.4 F .462(controls detect update con\215icts and pre)
72 534 R -.15(ve)-.25 G .462(nt o).15 F -.15(ve)-.15 G .462(rlapping changes.)
.15 F .462(In e)5.462 F .463(xperimental en)-.15 F .463
(vironments, where strong con-)-.4 F(trols are counterproducti)72 552 Q -.15
(ve)-.25 G 2.5(,i).15 G 2.5(ti)187.13 552 S 2.5(sp)195.19 552 S
(ossible to loosen the controls.)206.58 552 Q 1.165(Although RCS w)97 573.6 R
1.165(as originally intended for programs, it is useful for an)-.1 F 3.665(yt)
-.15 G -.15(ex)403.77 573.6 S 3.664(tt).15 G 1.164(hat is re)422.284 573.6 R
1.164(vised frequently and)-.25 F .743(whose pre)72 591.6 R .743(vious re)-.25
F .743(visions must be preserv)-.25 F 3.243(ed. RCS)-.15 F .744
(has been applied successfully to store the source te)3.243 F .744(xt for dra)
-.15 F(w-)-.15 E(ings, VLSI layouts, documentation, speci\214cations, test dat\
a, form letters and articles.)72 609.6 Q .662
(This paper discusses the practice of v)97 631.2 R .661
(ersion control using RCS.)-.15 F .661(It also introduces basic v)5.661 F .661
(ersion control con-)-.15 F 1.107
(cepts, useful for clarifying current practice and designing similar systems.)
72 649.2 R(Re)6.107 E 1.107(vision groups of indi)-.25 F 1.108(vidual compo-)
-.25 F .227(nents are treated in the ne)72 667.2 R .226
(xt three sections, and the e)-.15 F .226(xtensions to con\214gurations follo)
-.15 F 4.026 -.65(w. B)-.25 H .226(ecause of its size, a surv).65 F -.15(ey)
-.15 G(of v)72 685.2 Q(ersion control tools appears at the end of the paper)
-.15 E(.)-.55 E .32 LW 76 698 72 698 DL 80 698 76 698 DL 84 698 80 698 DL 88
698 84 698 DL 92 698 88 698 DL 96 698 92 698 DL 100 698 96 698 DL 104 698 100
698 DL 108 698 104 698 DL 112 698 108 698 DL 116 698 112 698 DL 120 698 116 698
DL 124 698 120 698 DL 128 698 124 698 DL 132 698 128 698 DL 136 698 132 698 DL
140 698 136 698 DL 144 698 140 698 DL/F4 8/Times-Roman@0 SF(An earlier v)72 708
Q(ersion of this paper w)-.12 E(as published in)-.08 E/F5 8/Times-Italic@0 SF
(Softwar)2 E(e\212Pr)-.296 E(actice & Experience)-.12 E/F6 8/Times-Bold@0 SF
(15)3.333 E F4 2(,7\()C(July 1985\), 637-654.)361.781 708 Q EP
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/F0 10/Times-Roman@0 SF 272.71(PSD:13-2 RCS)72 54 R 2.5(\212AS)2.5 G
(ystem for V)435.84 54 Q(ersion Control)-1.11 E/F1 10/Times-Bold@0 SF 2.5
(2. Getting)72 90 R(started with RCS)2.5 E F0(Suppose a te)97 111.6 Q
(xt \214le)-.15 E/F2 10/Times-Italic@0 SF -.15(f.)2.5 G(c).15 E F0
(is to be placed under control of RCS.)2.5 E(In)5 E -.2(vo)-.4 G
(king the check-in command).2 E F2 2.5(ci f)108 129.6 R(.c)-.15 E F0 .448
(creates a ne)72 153.6 R 2.948(wr)-.25 G -.25(ev)132.784 153.6 S .448
(ision group with the contents of).25 F F2 -.15(f.)2.948 G(c).15 E F0 .449
(as the initial re)2.948 F .449
(vision \(numbered 1.1\) and stores the group into)-.25 F 1.654(the \214le)72
171.6 R F2 -.15(f.)4.154 G(c,v).15 E F0 6.654(.U)C 1.654
(nless told otherwise, the command deletes)138.192 171.6 R F2 -.15(f.)4.154 G
(c).15 E F0 6.654(.I)C 4.154(ta)341.54 171.6 S 1.653
(lso asks for a description of the group.)352.914 171.6 R(The)6.653 E .909
(description should state the common purpose of all re)72 189.6 R .909
(visions in the group, and becomes part of the group')-.25 F 3.409(sd)-.55 G
(ocu-)522.23 189.6 Q 2.916(mentation. All)72 207.6 R .415
(later check-in commands will ask for a log entry)2.916 F 2.915(,w)-.65 G .415
(hich should summarize the changes made.)344.77 207.6 R(\(The)5.415 E
(\214rst re)72 225.6 Q(vision is assigned a def)-.25 E
(ault log message, which just records the f)-.1 E
(act that it is the initial re)-.1 E(vision.\))-.25 E .463(Files ending in)97
247.2 R F2(,v)2.963 E F0 .463(are called)2.963 F F2 .463(RCS \214les)2.963 F F0
(\()2.963 E F2(v)A F0 .463(stands for)2.963 F F2(v)2.963 E F0 .463
(ersions\); the others are called w)B .463(orking \214les.)-.1 F 2.063 -.8
(To g)5.463 H .463(et back).8 F(the w)72 265.2 Q(orking \214le)-.1 E F2 -.15
(f.)2.5 G(c).15 E F0(in the pre)2.5 E(vious e)-.25 E(xample, e)-.15 E -.15(xe)
-.15 G(cute the check-out command:).15 E F2 2.5(co f)108 283.2 R(.c)-.15 E F0
.277(This command e)72 307.2 R .277(xtracts the latest re)-.15 F .276
(vision from the re)-.25 F .276(vision group)-.25 F F2 -.15(f.)2.776 G(c,v).15
E F0 .276(and writes it into)2.776 F F2 -.15(f.)2.776 G(c).15 E F0 5.276(.T)C
.276(he \214le)454.04 307.2 R F2 -.15(f.)2.776 G(c).15 E F0 .276(can no)2.776 F
2.776(wb)-.25 G(e)535.56 307.2 Q(edited and, when \214nished, check)72 325.2 Q
(ed back in with)-.1 E F2(ci)2.5 E F0(:)A F2 2.5(ci f)108 343.2 R(.c)-.15 E(Ci)
72 367.2 Q F0(assigns number 1.2 to the ne)2.5 E 2.5(wr)-.25 G -.25(ev)210.63
367.2 S 2.5(ision. If).25 F F2(ci)2.5 E F0(complains with the message)2.5 E F2
(ci err)108 385.2 Q(or: no loc)-.45 E 2.5(ks)-.2 G(et by <lo)179.56 385.2 Q
(gin>)-.1 E F0 1.187(then the system administrator has decided to con\214gure \
RCS for a production en)72 409.2 R 1.188(vironment by enabling the `strict)-.4
F .589(locking feature'.)72 427.2 R .588(If this feature is enabled, all RCS \
\214les are initialized such that check-in operations require a lock)5.589 F
.343(on the pre)72 445.2 R .343(vious re)-.25 F .343
(vision \(the one from which the current one e)-.25 F -.2(vo)-.25 G(lv).2 E
2.844(ed\). Locking)-.15 F(pre)2.844 E -.15(ve)-.25 G .344(nts o).15 F -.15(ve)
-.15 G .344(rlapping modi\214cations).15 F 1.395(if se)72 463.2 R -.15(ve)-.25
G 1.395(ral people w).15 F 1.395(ork on the same \214le.)-.1 F 1.395
(If locking is required, the re)6.395 F 1.395(vision should ha)-.25 F 1.694
-.15(ve b)-.2 H 1.394(een lock).15 F 1.394(ed during the)-.1 F
(check-out by using the option)72 481.2 Q F2<ad6c>2.5 E F0(:)A F2 2.5
(co \255l f)108 499.2 R(.c)-.15 E F0 .564(Of course it is too late no)72 523.2
R 3.064(wf)-.25 G .564(or the check-out with locking, because)189.848 523.2 R
F2 -.15(f.)3.064 G(c).15 E F0 .564(has already been changed; checking out the)
3.064 F .166(\214le ag)72 541.2 R .166(ain w)-.05 F .166(ould o)-.1 F -.15(ve)
-.15 G .166(rwrite the modi\214cations.).15 F(\(T)5.166 E 2.666(op)-.8 G(re)
278.282 541.2 Q -.15(ve)-.25 G .166(nt accidental o).15 F -.15(ve)-.15 G
(rwrites,).15 E F2(co)2.666 E F0 .165(senses the presence of a w)2.665 F
(orking)-.1 E 1.147(\214le and asks whether the user really intended to o)72
559.2 R -.15(ve)-.15 G 1.148(rwrite it.).15 F 1.148(The o)6.148 F -.15(ve)-.15
G 1.148(rwriting check-out is sometimes useful for).15 F(backing up to the pre)
72 577.2 Q(vious re)-.25 E 2.5(vision.\) T)-.25 F 2.5(ob)-.8 G 2.5(ea)240.96
577.2 S(ble to proceed with the check-in in the present case, \214rst e)252.34
577.2 Q -.15(xe)-.15 G(cute).15 E F2 -.37(rc)108 595.2 S 5<73ad>.37 G 5(lf)
131.6 595.2 S(.c)142.01 595.2 Q F0 .829(This command retroacti)72 619.2 R -.15
(ve)-.25 G .829(ly locks the latest re).15 F .828
(vision, unless someone else lock)-.25 F .828(ed it in the meantime.)-.1 F .828
(In this case,)5.828 F(the tw)72 637.2 Q 2.5(op)-.1 G(rogrammers in)109.12
637.2 Q -.2(vo)-.4 G(lv).2 E(ed ha)-.15 E .3 -.15(ve t)-.2 H 2.5(on).15 G -.15
(eg)233 637.2 S(otiate whose modi\214cations should tak).15 E 2.5(ep)-.1 G
(recedence.)405.24 637.2 Q .06(If an RCS \214le is pri)97 658.8 R -.25(va)-.25
G .061(te, i.e., if only the o).25 F .061(wner of the \214le is e)-.25 F .061
(xpected to deposit re)-.15 F .061(visions into it, the strict lock-)-.25 F
.069(ing feature is unnecessary and may be disabled.)72 676.8 R .069
(If strict locking is disabled, the o)5.069 F .069
(wner of the RCS \214le need not ha)-.25 F -.15(ve)-.2 G 3.162(al)72 694.8 S
.662(ock for check-in.)82.382 694.8 R -.15(Fo)5.662 G 3.162(rs).15 G .662
(afety reasons, all others still do.)178.19 694.8 R -.45(Tu)5.662 G .662
(rning strict locking of).45 F 3.163(fa)-.25 G .663
(nd on is done with the com-)424.362 694.8 R(mands:)72 712.8 Q EP
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/F0 10/Times-Roman@0 SF(RCS \212 A System for V)72 48 Q(ersion Control)-1.11 E
(PSD:13-3)500.55 48 Q/F1 10/Times-Italic@0 SF -.37(rc)108 90 S 5<73ad>.37 G 5
(Uf)131.6 90 S(.c)146.45 90 Q F0(and)170.89 90 Q F1 -.37(rc)207.83 90 S 5<73ad>
.37 G 5(Lf)231.43 90 S(.c)244.62 90 Q F0 .317(These commands enable or disable\
 the strict locking feature for each RCS \214le indi)72 114 R(vidually)-.25 E
5.317(.T)-.65 G .316(he system administra-)451.598 114 R
(tor only decides whether strict locking is enabled initially)72 132 Q(.)-.65 E
1.845 -.8(To r)97 153.6 T .245(educe the clutter in a w).8 F .245
(orking directory)-.1 F 2.745(,a)-.65 G .246(ll RCS \214les can be mo)281.53
153.6 R -.15(ve)-.15 G 2.746(dt).15 G 2.746(oas)392.154 153.6 S .246
(ubdirectory with the name)410.976 153.6 R F1(RCS)2.746 E F0(.)A .56
(RCS commands look \214rst into that directory for RCS \214les.)72 171.6 R .56
(All the commands presented abo)5.56 F .86 -.15(ve w)-.15 H .56(ork with the)
.05 F F1(RCS)3.06 E F0(subdirectory without change.\207)72 189.6 Q .213
(It may be undesirable that)97 211.2 R F1(ci)2.713 E F0 .214(deletes the w)
2.713 F .214(orking \214le.)-.1 F -.15(Fo)5.214 G 2.714(ri).15 G .214
(nstance, sometimes one w)335.458 211.2 R .214(ould lik)-.1 F 2.714(et)-.1 G
2.714(os)481.318 211.2 S -2.25 -.2(av e)492.922 211.2 T .214(the cur)2.914 F(-)
-.2 E(rent re)72 229.2 Q(vision, b)-.25 E(ut continue editing.)-.2 E(In)5 E -.2
(vo)-.4 G(king).2 E F1 2.5(ci \255l f)108 247.2 R(.c)-.15 E F0 .124(checks in)
72 271.2 R F1 -.15(f.)2.624 G(c).15 E F0 .124(as usual, b)2.624 F .124
(ut performs an additional check-out with locking afterw)-.2 F 2.624
(ards. Thus,)-.1 F .124(the w)2.624 F .123(orking \214le does not)-.1 F 1.354
(disappear after the check-in.)72 289.2 R(Similarly)6.354 E 3.854(,t)-.65 G
1.354(he option)241.42 289.2 R F1<ad75>3.854 E F0 1.354(does a check-in follo)
3.854 F 1.355(wed by a check-out without locking.)-.25 F .693(This option is u\
seful if the \214le is needed for compilation after the check-in.)72 307.2 R
.693(Both options update the identi\214cation)5.693 F(mark)72 325.2 Q
(ers in the w)-.1 E(orking \214le \(see belo)-.1 E(w\).)-.25 E
(Besides the operations)97 346.8 Q F1(ci)2.5 E F0(and)2.5 E F1(co)2.5 E F0 2.5
(,R)C(CS pro)237.26 346.8 Q(vides the follo)-.15 E(wing commands:)-.25 E F1
(ident)72 364.8 Q F0 -.15(ex)123.37 364.8 S(tract identi\214cation mark).15 E