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.de X
.ie '\\n(.z'' \\!x X \\$1 \\$2 \\$3
.el \\!.X \\$1 \\$2 \\$3
..
.ds sd /usr/lib/tmac
.\"	RT -  reset everything to normal state
.de RT
.if !\\n(1T .BG
.ce 0
.if !\\n(IK .if !\\n(IF .if !\\n(IX .if !\\n(BE .di
.ul 0
.if \\n(QP \{\
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.el .if !\\n(IR \{\
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.if !\\n(AB .ft 1
.ta 5n 10n 15n 20n 25n 30n 35n 40n 45n 50n 55n 60n 65n 70n 75n 80n
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..
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.de IZ
.so \\*(sd/tmac.sdisp
.nr TN 0
.em EM
. \"  ACCENTS  say \*'e or \*`e to get e acute or e grave
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.ds v \\\\k:\\\\h'+\\\\w'e'u/4u'\\\\v'-0.6m'\\\\s6v\\\\s0\\\\v'0.6m'\\\\h'|\\\\n:u'
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.ch FO \\n(YYu
.if !\\n(FM .nr FM .7i
.nr YY -\\n(FMu
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.nr QI 5n
.nr I0 \\n(PIu
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.ev
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.wh 0 NP
.wh -\\n(FMu FO
.ch FO 16i
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.ch FO -\\n(FMu
.wh -\\n(FMu+.5v BT   \" was 1v
.nr CW 0-1
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..
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.de TL
.IZ
.rm IZ
.br
....sp |\\nx
....CO
.nr X .5i
....X "SP \\nX TL"
.nr TV 1
.ME
.rm ME
.di WT
.na
.fi
.ll \\n(LLu-.5i
.ft 1
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..
.de TX
.rs
.sp .5i
.ce 1000
.if n .ul 1000
.ps 12
.ft 3
.vs 15p
.ne 4
.hy 0
.WT
.hy 14
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.nf
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..
.de AX
.ft 1
.rs
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..
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.br
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.WS .4i
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\s9SUMMARY\s0
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..
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..
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..
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..
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'lt \\n(LLu
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..
.de PS	\" start picture
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.br
.nr X 0.35v
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.if \\$1>0 .sp .35
.ie \\$1>0 .nr $1 \\$1
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.in (\\n(.lu-\\$2)/2u
.ne \\$1
..
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.in
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..
.de ME
.nr SJ \\n(.j
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.if \\n(mo-9 .ds MO October
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.if "\\*(DY"" .ds DY \\*(MO \\n(dy, 19\\n(yr
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..
.	\"EM end up macro - process left over keep-release
.de EM
.br
.if \\n(AJ .tm Syntax error: no .AE
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..
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.CM
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'sp |\\n(HMu/2u
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.nr PX \\n(.s
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.nr PV \\n(.v
.lt \\n(LTu
.ps \\n(PS
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....nr Po \\n(.ou
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.PT
....po \\n(Pou
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'sp |\\n(HMu
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.mk
.os
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.ns
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\}
.mk #T
..
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.nf
.ls 1
.in 0
.rn KJ KL
.KL
.rm KL
.if "\\n(.z"KJ" .di
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.br
.in
.ls
.fi
.if (\\n(nl+1v)>(\\n(.p-\\n(FM) \{\
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.nr TD 0
..
.de KD
.nr KM 0
.if "\\n(.z"" .if \\$2>0 .if \\n(nl>\\n(HM \{\
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.if "\\n(.z"" .if \\n(nl>\\n(HM .if \\$2=0 .if (\\n(nl+1v)>(\\n(.p-\\n(FM) .sp 15i
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.nr KR \\n(.t
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.if \\n(KM=0 \{\
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.		di KJ
.		nr KM 1\}
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.rs
.if \\n(KM=0 .if \\$2>0 .sp \\n(.tu-\\$1u
..
.de PT
.lt \\n(LLu
.pc %
.nr PN \\n%
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.if \\n%-1 .if e .tl '\\n(PN'\s7\\*(Tl\s0''
.if \\n%-1 .if o .tl ''\s7\\*(Tr\s0'\\n(PN'
.lt \\n(.lu
..
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.nr FC +1
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..... probably ought to be just below after the .RC
.if \\n(FC<=1 .if \\n(XX .XF
.rn FZ FO
.nr MF 0
.if \\n(dn  .nr MF 1
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.	ch FO \\n(YYu\}
.if !\\n(dn .nr WF 0
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.nr FC -1
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..
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.de 2C
.MC \" default MC is double column
..
.de MH
A\^T\|\|&\|\|T Bell Laboratories, 600 Mountain Avenue, Murray Hill, NJ 07974 U.S.A.
..
.de BT
.ev 1
.nr Ss \\n(.s
.nr Sf \\n(.f
.ps \\n(PS
.vs \\n(VSp
.lt \\n(LLu
.ft 1
.nr yr \\n(yr%1900
.af NU 01
.af VN 01
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.\" price = 1.00 if <= 10 pages, otherwise .10/page.
.nr p1 (1+\\n(P>-\\n(P<)*10
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.nr p2 \\n(p1%100
.nr p1 \\n(p1/100
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.if \\n(Pf=0 .pl +.6i
.nr Pf \\n(Pf+1
.af % 1
.ps \\n(Ss
.ft \\n(Sf
.ev
..
.	\"PP - paragraph
.de PP
.RT
.if \\n(SH .sp .5
.nr SH 0
.if \\n(1T .X "SP \\n(PD PP"
.if \\n(1T .sp \\n(PDu
.ti +\\n(PIu
..
.	\"SH - (unnumbered) section heading
.de SH
.ti \\n(.iu
.RT
.nr X 1v
.if \\n(1T .X "SP \\nX SH
.ie \\n(1T .sp 2
.el .BG
.RT
.ne 4
.nr Sh 1
.if \\n(.$ .nr Sh \\$1
.if \\n(Sh=1 .ce
.if \\n(Sh=2 .ft B
.if \\n(Sh=3 .ft I
.nr SH 1
..
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.de NH
.RT
.nr X 1v
.if \\n(1T .X "SP \\nX NH"
.ie \\n(1T .sp 2
.el .BG
.RT
.ne 4
.if n .ul 1000
.ce
.nr NS \\$1
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.if !\\n(NS .nr NS 1
.nr H\\n(NS +1
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.if !\\n(NS-3 .nr H4 0
.if !\\n(NS-2 .nr H3 0
.if !\\n(NS-1 .nr H2 0
.if !\\$1 .if \\n(.$ .nr H1 1
.ds SN \\n(H1.
.ti \\n(.iu
.if \\n(NS-1 .as SN \\n(H2.
.if \\n(NS-2 .as SN \\n(H3.
.if \\n(NS-3 .as SN \\n(H4.
.if \\n(NS-4 .as SN \\n(H5.
\\*(SN
..
.	\"BG - begin, execute at first PP
.de BG
.br
.ME
.rm ME
.di
.ce 0
.nr KI 0
.hy 14
.nr 1T 1
.S\\n(ST
.rm S0 S1 S2 S3 OD OK TX AX WT TM IM MF MR RP I1 I2 I3 I4 I5 CB E1 E2
.de TL
.ft 3
.sp
.if n .ul 100
.ce 100
.ps +2
\\..
.RA
.rm RA
.rn FJ FS
.rn FK FE
.nf
.ev 1
.ps \\n(PS-2
.vs \\n(.s+1p
.ev
.if !\\n(KG .nr FP 0 
.if \\n(GA>1 .if \\n(KG=0 .nr GA 0 \" next UNIX must be flagged.
.nr KG 0 
.if \\n(FP \{\
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.	FG
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.br
.if t .if \\n(TV .sp 1
.fi
.ll \\n(LLu
.ev 1
.if !\\n(FL .nr FL \\n(LLu*11u/12u
.ll \\n(FLu
.ev
..
.	\"IP - indented paragraph
.de IP
.RT
.if !\\n(IP .nr IP +1
.ie \\n(ID>0 .X "SP \\n(ID IP"
.el .X "SP \\n(PD IP"
.ie \\n(ID>0 .sp \\n(IDu
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.nr IU \\n(IR+1
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.in \\n(I\\n(IUu
.nr TY \\n(TZ-\\n(.i
.nr JQ \\n(I\\n(IU-\\n(I\\n(IR
.ta \\n(JQu \\n(TYuR
.if \\n(.$ \{\
.ti \\n(I\\n(IRu
\&\\$1\t\c\}
..
.	\"LP - left aligned (block) paragraph
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.ti \\n(.iu
.RT
.if \\n(SH .sp .5
.nr SH 0
.if \\n(1T .X "SP \\n(PD LP"
.if \\n(1T .sp \\n(PDu
..
.de QP
.ti \\n(.iu
.RT
.if \\n(1T .X "SP \\n(PD QP"
.if \\n(1T .sp \\n(PDu
.ne 1.1
.nr QP 1
.in +\\n(QIu
.ll -\\n(QIu
.ti \\n(.iu
..
.	\"IE - synonym for .LP
.de IE
.LP
..
.	\"RS - prepare for double indenting
.de RS
.nr IS \\n(IP
.RT
.nr IP \\n(IS
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.nr IR +1
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.in \\n(I\\n(IRu
.nr TY \\n(TZ-\\n(.i
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..
.	\"RE - retreat to the left
.de RE
.nr IS \\n(IP
.RT
.nr IP \\n(IS
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.in \\n(I\\n(IRu
..
.de TC
.nr TZ \\n(.lu
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AT&T Bell Laboratories
Holmdel, New Jersey 07733
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AT&T Bell Laboratories
Whippany, New Jersey 07981
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AT&T Bell Laboratories
Naperville, Illinois 60540
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SOFTWARE\(emPRACTICE AND EXPERIENCE, VOL. \\*(VN(\\*(NU), \\n(P<-\\n(P> (\\*(MO 19\\n(yr)
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