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72 293.4 R 2.929(yi)-.05 G 2.929(ss)-2.929 G 2.929(oc)-2.929 G .429
(lose, that it could in f)-2.929 F .429(act easily be used to implement)
-.1 F .017(the ECA)72 305.4 R 2.517(TI)-1.11 G(nde)-2.517 E 2.517(xd)
-.15 G .017(atabase. Ho)-2.517 F(we)-.25 E -.15(ve)-.25 G .817 -.4(r, d)
.15 H .017(irect access to directory \214les \212 through the deprecate\
d \231struct direct\232).4 F 2.962<8a69>72 317.4 S 2.962(sf)-2.962 G(ro)
-2.962 E .461(wned upon today)-.25 F 2.961(,w)-.65 G .461(hich mak)
-2.961 F .461(es lar)-.1 F .461(ge directories a bit a)-.18 F(wkw)-.15 E
.461(ard. It is also con)-.1 F -.15(ve)-.4 G .461(nient to ha).15 F .761
-.15(ve a)-.2 H(ddi-).15 E .504
(tional information in the directory \214le \()72 329.4 R/F3 10
/Times-Italic@0 SF(i.e)A(.)-.15 E F2 3.005(,i)C .505
(nstead of storing the information in a data \214le\). This informa-)
-3.005 F .978(tion could be \231hidden\232 in the \214le name, gi)72
341.4 R -.15(ve)-.25 G 3.478(nt).15 G .978(he lar)-3.478 F .978
(ge \214le component sizes allo)-.18 F .977(wed in modern \214le sys-)
-.25 F(tems, b)72 353.4 Q(ut this too is clumsy)-.2 E(.)-.65 E F0 2.5
(2.2. GDBM)72 377.4 R F2 -.15(Fo)72 393.6 S 3.273(rt).15 G .773
(he reasons discussed abo)-3.273 F -.15(ve)-.15 G 3.273(,t).15 G .773
(he ECA)-3.273 F 3.273(TI)-1.11 G(nde)-3.273 E 3.273(xd)-.15 G .773
(atabase is implemented as a gdbm database. The k)-3.273 F -.15(ey)-.1 G
(s).15 E .656
(are pseudo-inodes, arti\214cially generated as the database is b)72
405.6 R .656(uilt. A v)-.2 F .656
(alue is a sequence of entries \212 much)-.25 F(lik)72 417.6 Q 3.084
<6599>-.1 G .585(struct direct\232. There are actually no data \214les:\
 the URL information that is logically contained in the)-3.084 F
(data \214le is k)72 429.6 Q(ept in the directory entry)-.1 E(.)-.65 E
.022(Directory entries are al)72 445.8 R -.1(wa)-.1 G .022(ys added \
\231in order\232, so that no sorting is required at run-time. Directori\
es are con-).1 F .888(strained not to e)72 457.8 R .888
(xceed a \231reasonable\232 size: lar)-.15 F .888
(ge directories are arti\214cially brok)-.18 F .888
(en into a series of smaller)-.1 F .467(directories, link)72 469.8 R
.467
(ed together for sequential access. Directory entries are either name/k)
-.1 F .767 -.15(ey p)-.1 H .467(airs or name/URL).15 F(pairs.)72 481.8 Q
F0 2.5(2.3. Dir)72 505.8 R(ect Sear)-.18 E(ches)-.18 E F2(Abo)72 522 Q
.331 -.15(ve i)-.15 H 2.531(tw).15 G .031
(as noted that directory entries are k)-2.631 F .031
(ept \231in order\232 to e)-.1 F .032
(xpedite \231direct searches\232. As implication of)-.15 F .088
(this is that multi-w)72 534 R .087
(ord names should be arranged from most important to least important w)
-.1 F(ord.)-.1 E F3(E.g)2.587 E(.)-.15 E F2 2.587<2c99>C(paper)-2.587 E
(,)-.4 E .98
(\214lter\232, not \231\214lter paper\232. This applies equally to cate)
72 546 R .981(gory names created by the MIT ECA)-.15 F 3.481(Tt)-1.11 G
.981(eam, and to)-3.481 F(product item names created by the v)72 558 Q
(arious v)-.25 E(endors.)-.15 E .082(Nothing other than le)72 574.2 R
.082(xicographic searches are supported \212 the goal is to mimic the f\
unctionality of a paper)-.15 F .714(catalogue inde)72 586.2 R .714
(x. Support for pattern matching, e)-.15 F -.15(ve)-.25 G 3.215(nf).15 G
.715(or re)-3.215 F .715(gular e)-.15 F .715
(xpressions, could certainly be added in a)-.15 F
(later release, if such functionality were desired by the general ECA)72
598.2 Q 2.5(Tu)-1.11 G(ser)-2.5 E(.)-.55 E F0(Pr)72 756 Q 132.005
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96 R/F2 10/Times-Roman@0 SF 1.193(The taxonomy \212 the breakdo)72 124.2
R 1.192(wn into cate)-.25 F 1.192(gories \212 is pro)-.15 F 1.192
(vided by the MIT Customer)-.15 F 1.192(-Supplier Services)-.2 F 1.026
(group, and the product items are pro)72 136.2 R 1.027(vided by the v)
-.15 F 1.027(endors. This is not a technical requirement \212 from a)
-.15 F 1.554(technical point of vie)72 148.2 R 4.054(wi)-.25 G 4.054(tm)
-4.054 G(ak)-4.054 E 1.554(es no dif)-.1 F 1.553(ference whatsoe)-.25 F
-.15(ve)-.25 G 4.053(rh).15 G 2.053 -.25(ow t)-4.053 H 1.553
(he tree is de\214ned \212 b).25 F 1.553(ut is a)-.2 F/F3 10
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160.2 R 1.476(endor w)-.15 F 1.476(as allo)-.1 F 1.477(wed \(or w)-.25 F
1.477(orse, required\) to supply their o)-.1 F 1.477(wn branches, the o)
-.25 F -.15(ve)-.15 G(rall).15 E(inde)72 172.2 Q 2.958(xt)-.15 G .458
(ree w)-2.958 F .458(ould no longer present the ECA)-.1 F 2.957(Tu)-1.11
G .457(ser with a single uni\214ed inde)-2.957 F .457(x. The tree w)-.15
F .457(ould be a bizarre)-.1 F
(collection of unrelated trees all grafted onto the basic ECA)72 184.2 Q
2.5(Tr)-1.11 G(oot stock \(to continue the botanical analogy\).)-2.5 E
F0 2.5(3.1. Cr)72 208.2 R(eation of an ECA)-.18 E 2.5(TI)-.95 G(ndex)
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-.25 E 2.5(TI)-1.11 G(nde)-2.5 E 2.5(xD)-.15 G(B:)-2.5 E 12.5(\(1\) the)
77 240.6 R .508(MIT ECA)3.008 F 3.008(Tt)-1.11 G .508
(eam de\214nes a taxonomy)-3.008 F(,)-.65 E F3(i.e)3.008 E(.)-.15 E F2
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(gories, and pro)-.15 F .509(vides the list to)-.15 F(all ECA)103.66
252.6 Q 2.5(Tv)-1.11 G(endors.)-2.65 E 12.5(\(2\) the)77 268.8 R -.15
(ve)2.857 G .356(ndors supply a list of items and URL).15 F 1.456 -.55
('s c)-.92 H .356(orresponding to the MIT ECA).55 F 2.856(Tt)-1.11 G
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(eam may wish to restrict the number of items,)-3.208 F F3(i.e)3.209 E
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G 3.209(fd)-3.209 G .709(etail which a v)-3.209 F(endor)-.15 E
(may present.)103.66 294.8 Q/F4 7/Times-Roman@0 SF(1)-4 I F2 12.5
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(ystem administrator\232 compiles all the v)-3.394 F(endor)-.15 E .893
(-supplied information into a single)-.2 F(ECA)103.66 323 Q 3.262(TI)
-1.11 G(nde)-3.262 E 3.262(xd)-.15 G .762
(atabase. Some iteration may be required, if for e)-3.262 F .762
(xample, the v)-.15 F .762(endor feels that addi-)-.15 F(tional cate)
103.66 335 Q(gories are required, or if the v)-.15 E
(endor presents an inappropriate le)-.15 E -.15(ve)-.25 G 2.5(lo).15 G
2.5(fd)-2.5 G(etail.)-2.5 E 12.5(\(4\) at)77 351.2 R 2.718(aw)2.718 G
.218(ell-de\214ned time \212 say Saturday e)-2.718 F -.15(ve)-.25 G .218
(ning at midnight \212 the MIT ECA).15 F 2.718(Ts)-1.11 G .218
(ystem administrator)-2.718 F .522(switches to the ne)103.66 363.2 R
3.022(wE)-.25 G(CA)-3.022 E 3.022(TI)-1.11 G(nde)-3.022 E .523
(x. This allo)-.15 F .523(ws v)-.25 F .523
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377.2 Q -.55('s)-.92 G(.).55 E F4(2)-4 I F0 2.5(3.2. Updating)72 401.2 R
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2.792(Tt)-1.11 G .292(eam must de\214ne a process by which the inde)
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(pdated. This is particularly important if)-2.791 F .413(the URL)72
429.4 R 1.513 -.55('s p)-.92 H .413(oint to an).55 F .414
(ything other than the v)-.15 F .414
(endor homepages, since in that case, there are synchronization)-.15 F
(issues.)72 441.4 Q .32 LW 76 646 72 646 DL 80 646 76 646 DL 84 646 80
646 DL 88 646 84 646 DL 92 646 88 646 DL 96 646 92 646 DL 100 646 96 646
DL 104 646 100 646 DL 108 646 104 646 DL 112 646 108 646 DL 116 646 112
646 DL 120 646 116 646 DL 124 646 120 646 DL 128 646 124 646 DL 132 646
128 646 DL 136 646 132 646 DL 140 646 136 646 DL 144 646 140 646 DL 148
646 144 646 DL 152 646 148 646 DL 156 646 152 646 DL 160 646 156 646 DL
164 646 160 646 DL 168 646 164 646 DL 172 646 168 646 DL 176 646 172 646
DL 180 646 176 646 DL 184 646 180 646 DL 188 646 184 646 DL 192 646 188
646 DL 196 646 192 646 DL 200 646 196 646 DL 204 646 200 646 DL 208 646
204 646 DL 212 646 208 646 DL 216 646 212 646 DL/F5 5/Times-Roman@0 SF
(1)93.6 656.4 Q/F6 8/Times-Roman@0 SF .613(E.g., VWR Scienti\214c)3.2 J
/F7 8/Times-Italic@0 SF(could)2.613 E F6 .612
(supply the names of 100 dif)2.613 F .612(ferent types of pipettes \212\
 \231pipette, 1 ml, 10 cm\232, \231pipette, 2 ml, 10)-.2 F(cm\232,)72
669.2 Q F7(etc.)2.184 E F6 2.184<8a6f>2.184 G 2.184(rt)-2.184 G(he)
-2.184 E 2.184(yc)-.12 G .184
(ould supply the single generic name \231pipette\232. F)-2.184 F .184
(or the sak)-.12 F 2.184(eo)-.08 G 2.185(fu)-2.184 G(niformity)-2.185 E
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(eam should specify the de-)-2.185 F(sired le)72 678.8 Q -.12(ve)-.2 G 2
(lo).12 G 2(fd)-2 G(etail.)-2 E F5(2)93.6 689.2 Q F6
(This assumes, of course, that the v)3.2 I(endor URL)-.12 E .88 -.44
('s d)-.736 H 2(oi).44 G 2(nf)-2 G(act point to lo)-2.08 E(wer)-.2 E
(-le)-.16 E -.12(ve)-.2 G 2(lp).12 G(ages and not just the v)-2 E
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(et Deli)-.14 E -.14(ve)-.14 G(rables).14 E/F2 10/Times-Roman@0 SF
(Netmark)72 124.2 Q(et will pro)-.1 E(vide the follo)-.15 E
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E 5<8363>77 140.4 S .853(onsulting on the design of the user interf)-5 F
.852(ace. The interf)-.1 F .852(ace will pro)-.1 F .852
(vide the ability to search by cate-)-.15 F
(gory and directly by item name.)85.5 152.4 Q 5<8343>77 164.4 S
(GI programs to dynamically create pages to na)-5 E(vig)-.2 E
(ate the hierarch)-.05 E 2.5(yo)-.05 G 2.5(fi)-2.5 G(tems.)-2.5 E 5
<8361>77 176.4 S(Mak)-1.995 E .505
(e\214le and programs to compile item/URL lists supplied by the v)-.1 F
.506(endors into a single ECA)-.15 F 3.006(TI)-1.11 G(nde)-3.006 E(x.)
-.15 E(The ECA)85.5 188.4 Q 2.5(TI)-1.11 G(nde)-2.5 E 2.5(xw)-.15 G
(ill consist of one or more gdbm databases.)-2.5 E F0 2.5(4.1. User)72
212.4 R(Interface)2.5 E F2 .952
(Each page will include a standard masthead, b)72 228.6 R .952
(ut no other graphics. There will be one basic page format.)-.2 F 1.004
(This will include an HTML list of \231items\232 \()72 240.6 R/F3 10
/Times-Italic@0 SF(i.e)A(.)-.15 E F2 3.504(,e)C 1.004
(ither product or cate)-3.504 F 1.004(gory names\); if there are suf)
-.15 F(\214cient)-.25 E 1.112(items \()72 252.6 R F3(i.e)A(.)-.15 E F2
3.612(,m)C 1.111(ore than some compile-time constant\), then the page w\
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-.15(ve)-.15 G(backw)72 264.6 Q(ards and forw)-.1 E
(ards laterally page by page, and a te)-.1 E
(xt input \214eld for direct searching.)-.15 E F0 2.5(4.2. CGI)72 288.6
R(Pr)2.5 E(ograms)-.18 E F2 .22
(The pages will be dynamically generated from the ECA)72 304.8 R 2.721
(TI)-1.11 G(nde)-2.721 E 2.721(xD)-.15 G .221(B. There will be se)-2.721
F -.15(ve)-.25 G .221(ral CGI programs at).15 F .902(most, perhaps e)72
316.8 R -.15(ve)-.25 G 3.401(no).15 G .901(nly one. The CGI program is \
written in C, and will directly access the ECA)-3.401 F 3.401(TI)-1.11 G
(nde)-3.401 E(x)-.15 E(DB.)72 328.8 Q F0 2.5(4.3. ECA)72 352.8 R 2.5(TI)
-.95 G(ndex Compilation)-2.5 E F2(NetMark)72 369 Q .89(et will pro)-.1 F
.89(vide a Mak)-.15 F .891
(e\214le and programs or scripts, as required, to generate the ECA)-.1 F
3.391(TI)-1.11 G(nde)-3.391 E 3.391(xD)-.15 G(B)-3.391 E .646
(from the information supplied by the MIT ECA)72 381 R 3.146(Tt)-1.11 G
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(endors. NetMark)-.15 F .645(et will docu-)-.1 F
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57(4.2 CGI)72 312 R .95(Programs ......................................\
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(eliminary A)-.18 F(pril 30, 1996)-.25 E(Con\214dential)133.195 E EP
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