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ASH.1：源码内容
							%!PS-Adobe-1.0
%%Creator: devps (Pipeline Associates, Inc.)
%%CreationDate: Fri Sep 13 13:03:10 1996
%%Pages: (atend)
%%DocumentFonts: (atend)
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systemdict /setpacking known
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/fontnum 1 def 
systemdict /setpacking known { savepacking setpacking} if
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0 1 255 {Encoding-1 exch /.notdef put} for
Encoding-1 8#301 StandardEncoding 8#101 26 getinterval putinterval %A-B
Encoding-1 8#341 StandardEncoding 8#141 26 getinterval putinterval %a-b
Encoding-1 8#241 StandardEncoding 8#301 16 getinterval putinterval %accents
Encoding-1 8#373 StandardEncoding 8#365 1 getinterval putinterval %dotlessi
Encoding-1
dup 8#41 /copyright put
dup 8#42 /registered put
dup 8#43 /trademark put
dup 8#44 /logicalnot put
dup 8#45 /Eth put
dup 8#46 /eth put
dup 8#47 /Thorn put
dup 8#50 /thorn put
dup 8#51 /brokenbar put
dup 8#52 /degree put
dup 8#53 /divide put
dup 8#54 /multiply put
dup 8#55 /minus put
dup 8#56 /onehalf put
dup 8#57 /onequarter put
dup 8#60 /threequarters put
dup 8#101 /Aacute put
dup 8#102 /Acircumflex put
dup 8#103 /Adieresis put
dup 8#104 /Agrave put
dup 8#105 /Aring put
dup 8#106 /Atilde put
dup 8#107 /Ccedilla put
dup 8#110 /Eacute put
dup 8#111 /Ecircumflex put
dup 8#112 /Edieresis put
dup 8#113 /Egrave put
dup 8#114 /Iacute put
dup 8#115 /Icircumflex put
dup 8#116 /Idieresis put
dup 8#117 /Igrave put
dup 8#120 /Ntilde put
dup 8#121 /Oacute put
dup 8#122 /Ocircumflex put
dup 8#123 /Odieresis put
dup 8#124 /Ograve put
dup 8#125 /Otilde put
dup 8#126 /Scaron put
dup 8#127 /Uacute put
dup 8#130 /Ucircumflex put
dup 8#131 /Udieresis put
dup 8#132 /Ugrave put
dup 8#133 /Ydieresis put
dup 8#134 /Zcaron put
dup 8#135 /aacute put
dup 8#136 /acircumflex put
dup 8#137 /adieresis put
dup 8#140 /agrave put
dup 8#141 /aring put
dup 8#142 /atilde put
dup 8#143 /ccedilla put
dup 8#144 /eacute put
dup 8#145 /ecircumflex put
dup 8#146 /edieresis put
dup 8#147 /egrave put
dup 8#150 /iacute put
dup 8#151 /icircumflex put
dup 8#152 /idieresis put
dup 8#153 /igrave put
dup 8#154 /ntilde put
dup 8#155 /oacute put
dup 8#156 /ocircumflex put
dup 8#157 /odieresis put
dup 8#160 /ograve put
dup 8#161 /otilde put
dup 8#162 /scaron put
dup 8#163 /uacute put
dup 8#164 /ucircumflex put
dup 8#165 /udieresis put
dup 8#166 /ugrave put
dup 8#167 /ydieresis put
dup 8#170 /zcaron put
pop
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Enc-dict /tmpstr1 50 string put
Enc-dict /tmpstr2 50 string put
Enc-dict /tmpstr3 50 string dup (Encoding-) exch cvs pop put
/AEnc-def { % arguments: the original font's name, encoding nr
Enc-dict begin
tmpstr2 cvs /Enc-no exch def % Remember the number in a string
dup /OrigName exch def % remember the name
findfont dup maxlength dict /newdict exch def % get dictionary for new font
{ exch dup /FID ne
   { exch newdict 3 1 roll put }
   { pop pop } % Ignore FID
   ifelse
} forall
newdict begin
/Encoding
  tmpstr3 9 Enc-no putinterval tmpstr3 0 9 Enc-no length add getinterval
  cvn load
  def % Replace encoding
currentdict /UniqueID known
{ /UniqueID UniqueID Enc-no cvi 49999 mul add def } if % Derive New UniqueID
end % newdict
/FNlength OrigName tmpstr1 cvs length def % convert name, remember length
FNlength 1 add Enc-no length add string
dup 0 OrigName tmpstr1 cvs putinterval
dup FNlength (-) putinterval
dup FNlength 1 add Enc-no putinterval
dup 0 tmpstr1 0 FNlength getinterval putinterval % Add old name
cvn dup newdict /FontName 3 2 roll put newdict definefont
end % Enc-dict
} def
/Times-Roman 1 AEnc-def pop
/R-1{/Times-Roman-1 FF}def
/R{/Times-Roman FF}def
/B{/Times-Bold FF}def
/I{/Times-Italic FF}def
%%EndProlog
%%Page: 1 1
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10 R
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2304 V
10 B
864(Invocation)S
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1182(the)S
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2338(the)S
2498(standard)S
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1836(the)S
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1993(-s)S
10 R
2100(or)S
10 B
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2994(then)S
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3552(arg)S
10 R
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4730(a)S
4810(256le)S
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5087(read)S
2832 V
1080(commands)S
1547(from.)S
1825(If)S
1925(this)S
2102(is)S
2201(impossible)S
(because)319 2668 A
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3409(no)S
3541(arguments)S
3991(following)S
4413(the)S
4567(options,)S
4918(then)S
10 I
5122(ash)S
2952 V
10 R
(will)157 1080 A
1262(set)S
1399(the)S
10 B
1547(-s)S
10 R
1645(257ag)S
1821(and)S
(will)157 1991 A
2173(read)S
2372(commands)S
2832(from)S
3053(the)S
3201(standard)S
(input.)231 3567 A
3120 V
1080(The)S
1266(shell)S
1485(sets)S
1665(the)S
(initial)235 1817 A
2081(value)S
2328(of)S
2441(the)S
(positional)396 2593 A
3018(parameters)S
3490(from)S
3715(the)S
10 I
3867(arg)S
10 R
4014(s)S
4082(remaining)S
4519(after)S
4734(any)S
10 I
4908(arg)S
10 R
5077(used)S
3240 V
1080(as)S
1189(the)S
1337(name)S
1580(of)S
1689(a)S
1759(256le)S
1913(of)S
2022(commands)S
2482(is)S
2574(deleted.)S
3408 V
1080(The)S
1264(257ags)S
1481((other)S
1749(than)S
10 B
1949(-c)S
10 R
2028())S
2089(are)S
2240(set)S
2379(by)S
(preceding)397 2506 A
2930(them)S
3158(with)S
(``-'')170 3364 A
3561(and)S
3733(cleared)S
4052(by)S
(preceding)397 4179 A
4604(them)S
4833(with)S
5040(``+'';)S
3528 V
1080(see)S
1240(the)S
10 I
1394(set)S
10 R
(builtin)262 1537 A
1830(command)S
2257(for)S
2406(a)S
2482(list)S
2636(of)S
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4137(the)S
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4291(-i)S
10 R
4384(257ag,)S
4590(the)S
10 B
4743(-s)S
10 R
4846(257ag)S
5027(is)S
5124(set,)S
3648 V
1080(and)S
1253(the)S
1404(standard)S
(input)206 1773 A
2007(and)S
2180(output)S
2464(of)S
2576(the)S
2727(shell)S
2945(are)S
(connected)408 3097 A
3533(to)S
3639(terminals,)S
4067(then)S
4269(the)S
10 B
4421(-i)S
10 R
4512(257ag)S
(will)157 4692 A
4878(be)S
5002(set.)S
5193(If)S
3768 V
1080(no)S
1205(value)S
1448(is)S
1540(speci256ed)S
1923(for)S
2066(the)S
10 B
2214(-j)S
10 R
2307(257ag,)S
2508(then)S
2706(the)S
10 B
2854(-j)S
10 R
2947(257ag)S
(will)157 3123 A
3305(be)S
3425(set)S
3562(if)S
3649(the)S
10 B
3797(-i)S
10 R
3884(257ag)S
4060(is)S
4152(set.)S
3936 V
1080(When)S
1352(the)S
1507(shell)S
1729(is)S
(invoked)323 1828 A
2183(with)S
2394(the)S
10 B
2549(-c)S
10 R
2660(option,)S
2973(it)S
3061(is)S
(good)200 3160 A
3392(practice)S
3744(to)S
3854(include)S
4182(the)S
10 I
4337(-i)S
10 R
4431(257ag)S
4614(if)S
4709(the)S
4865(command)S
4056 V
1080(was)S
1274(entered)S
1608(interactively)S
2149(by)S
2286(a)S
2368(user.)S
2623(For)S
(compatibility)536 2800 A
3373(with)S
3589(the)S
3749(System)S
4082(V)S
4192(shell,)S
4444(the)S
10 I
4604(-i)S
10 R
4702(option)S
(should)267 4994 A
4176 V
1080(come)S
1323(after)S
1534(the)S
10 B
1682(-c)S
10 R
1786(option.)S
4344 V
1080(If)S
1179(the)S
1333(256rst)S
1521(character)S
1923(of)S
2038(argument)S
2449(zero)S
2654(to)S
2763(the)S
2917(shell)S
3138(is)S
(``-'',)195 3236 A
3463(the)S
3618(shell)S
3840(is)S
3939(assumed)S
4317(to)S
4427(be)S
4554(a)S
4631(login)S
4869(shell,)S
5116(and)S
4464 V
1080(the)S
1237(256les)S
10 B
1439(/etc/pro256le)S
10 R
1933(and)S
10 B
2112(.pro256le)S
10 R
2451(are)S
2609(read)S
2817(if)S
2913(they)S
3120(exist.)S
3394(If)S
3496(the)S
3652(environment)S
4193(variable)S
4551(SHINIT)S
4916(is)S
5016(set)S
5161(on)S
4584 V
1080(entry)S
1318(to)S
1427(the)S
1581(shell,)S
1827(the)S
1982(commands)S
2449(in)S
2559(SHINIT)S
2923(are)S
3079(normally)S
3474(parsed)S
3769(and)S
3946(executed.)S
4386(SHINIT)S
4750(is)S
4849(not)S
5009(exam-)S
4704 V
1080(ined)S
1281(if)S
1371(the)S
1522(shell)S
1740(is)S
1835(a)S
1908(login)S
2142(shell,)S
2385(or)S
2497(if)S
2587(it)S
2671(the)S
2822(shell)S
3040(is)S
(running)312 3135 A
3475(a)S
3548(shell)S
3766(procedure.)S
4272((A)S
4407(shell)S
4625(is)S
4720(considered)S
5183(to)S
4824 V
1080(be)S
(running)312 1200 A
1537(a)S
1607(shell)S
1822(procedure)S
2250(if)S
2337(neither)S
2642(the)S
10 B
2790(-s)S
10 R
2888(nor)S
3047(the)S
10 B
3195(-c)S
10 R
3299(options)S
3619(are)S
3768(set.))S
5064 V
10 B
864(Control)S
1225(Structures)S
5232 V
10 R
1080(A)S
10 I
1181(list)S
10 R
1332(is)S
1427(a)S
1500(sequence)S
1897(of)S
2009(zero)S
2211(or)S
2323(more)S
2558(commands)S
3021(separated)S
3430(by)S
3558(newlines,)S
3969(semicolons,)S
4474(or)S
4587(ampersands,)S
5116(and)S
5352 V
1080(optionally)S
1522(terminated)S
1988(by)S
2123(one)S
2303(of)S
2422(these)S
2664(three)S
2901(characters.)S
3396((This)S
3644(differs)S
3942(from)S
4172(the)S
4329(System)S
4659(V)S
4766(shell,)S
5015(which)S
5472 V
1080(requires)S
1433(a)S
1506(list)S
1657(to)S
1763(contain)S
2088(at)S
2190(least)S
2404(one)S
2578(command)S
3003(in)S
3110(most)S
3334(cases.))S
3660(The)S
3846(commands)S
4310(in)S
4417(a)S
4491(list)S
4643(are)S
4796(executed)S
5183(in)S
5592 V
1080(the)S
1232(order)S
1473(they)S
1674(are)S
(written.)311 1826 A
2190(If)S
2286(command)S
2710(is)S
2805(followed)S
3191(by)S
3319(an)S
3442(ampersand,)S
3931(the)S
4082(shell)S
4300(starts)S
4541(the)S
4692(command)S
5116(and)S
5712 V
1080(immediately)S
(proceed)319 1614 A
1964(onto)S
2174(the)S
2329(next)S
2534(command;)S
2990(otherwise)S
3414(it)S
3502(waits)S
3747(for)S
3897(the)S
4052(command)S
4480(to)S
4590(terminate)S
5003(before)S
5832 V
(proceeding)447 1080 A
1552(to)S
1655(the)S
1803(next)S
2001(one.)S
6000 V
1080(``&&'')S
1417(and)S
1607(``||'')S
1828(are)S
1997(binary)S
2299(operators.)S
2769(``&&'')S
3106(executes)S
3498(the)S
3666(256rst)S
3868(command,)S
4335(and)S
4526(then)S
4745(executes)S
5138(the)S
6120 V
(second)279 1080 A
1401(command)S
1839(iff)S
1977(the)S
2142(exit)S
2335(status)S
2606(of)S
2732(the)S
2897(256rst)S
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3534(is)S
3643(zero.)S
3909(``||'')S
4127(is)S
4235(similar,)S
4581(but)S
4750(executes)S
5138(the)S
6240 V
(second)279 1080 A
1394(command)S
1825(iff)S
1956(the)S
2114(exit)S
2300(status)S
2564(of)S
2683(the)S
2841(256rst)S
3033(command)S
3464(is)S
(nonzero.)349 3567 A
3977(``&&'')S
4305(and)S
4486(``||'')S
4698(both)S
4912(have)S
5138(the)S
6360 V
1080(same)S
1312(priority.)S
6528 V
1080(The)S
1272(``|'')S
1463(operator)S
1834(is)S
1937(a)S
2018(binary)S
2311(operator)S
2683(which)S
2965(feeds)S
3214(the)S
3373(standard)S
3750(output)S
4042(of)S
4162(the)S
4321(256rst)S
4514(command)S
4946(into)S
5138(the)S
6648 V
1080(standard)S
(input)206 1460 A
1705(of)S
1828(the)S
(second)279 1990 A
2308(command.)S
2792(The)S
2987(exit)S
3176(status)S
3443(of)S
3565(the)S
3726(``|'')S
3920(operator)S
4294(is)S
4399(the)S
4560(exit)S
4749(status)S
5016(of)S
5138(the)S
6768 V
(second)279 1080 A
1384(command.)S
1855(``|'')S
2036(has)S
2195(a)S
2265(higher)S
2547(priority)S
2874(than)S
3072(``||'')S
3273(or)S
3382(``&&''.)S
6936 V
1080(An)S
10 I
1228(if)S
10 R
1309(command)S
(looks)217 1730 A
1972(like)S
7176 V
10 B
1480(if)S
10 R
1567(list)S
7296 V
10 B
1480(then)S
10 R
1840(list)S
7416 V
1421([)S
10 B
1480(elif)S
10 R
1640(list)S
7536 V
10 B
1530(then)S
10 R
1840(list)S
1988(])S
(...)75 2047 A
7903 V
720(Page)S
941(1)S
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4455(September)S
4911(13,)S
(1996)200 5061 A
8143 V
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5227())S
960 V
1421([)S
10 B
1480(else)S
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1781(list)S
1929(])S
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1480(256)S
1368 V
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1080(A)S
10 I
1178(while)S
10 R
1421(command)S
(looks)217 1842 A
2084(like)S
1608 V
10 B
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1728 V
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10 I
(until)184 4560 A
10 R
4771(command)S
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2208 V
1080(similar,)S
1410(but)S
1563(has)S
1722(the)S
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10 B
2102(until)S
10 R
2329(in)S
(place)213 2432 A
2670(of)S
10 B
2779(while)S
2328 V
10 R
1105(repeats)S
(until)184 1416 A
1625(the)S
1773(exit)S
1949(status)S
2203(of)S
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2460(256rst)S
2642(list)S
2790(is)S
2882(zero.)S
2496 V
1080(The)S
10 I
1262(for)S
10 R
1404(command)S
(looks)217 1825 A
2067(like)S
2736 V
10 B
1480(for)S
10 R
1634(variable)S
10 B
1984(in)S
10 R
(word...)282 2093 A
2856 V
10 B
1480(do)S
10 R
1840(list)S
2976 V
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1480(done)S
3216 V
10 R
1080(The)S
1267(words)S
1543(are)S
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3306(repeatedly)S
3757(with)S
3967(the)S
4121(variable)S
4477(set)S
4620(to)S
(each)185 4729 A
4945(word)S
5183(in)S
3336 V
1080(turn.)S
10 B
1317(do)S
10 R
1448(and)S
10 B
1618(done)S
10 R
1850(may)S
2048(be)S
(replaced)342 2168 A
2535(with)S
2739(``{'')S
2948(and)S
3118(``}''.)S
3504 V
1080(The)S
10 I
1262(break)S
10 R
1516(and)S
10 I
1686(continue)S
10 R
2057(commands)S
(look)178 2517 A
2720(like)S
3744 V
10 B
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10 R
1757([)S
1816(num)S
2019(])S
3864 V
10 B
1480(continue)S
10 R
1875([)S
1934(num)S
2137(])S
4104 V
10 I
1080(Break)S
10 R
1353(terminates)S
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10 I
1960(num)S
10 R
2165(innermost)S
10 I
2599(for)S
10 R
2748(or)S
10 I
2864(while)S
10 R
(loops.)242 3115 A
10 I
3415(Continue)S
10 R
3816(continues)S
4234(with)S
4446(the)S
4602(next)S
4808(iteration)S
5177(of)S
4224 V
1080(the)S
10 I
1228(num'th)S
10 R
1538(innermost)S
(loop.)203 1965 A
2218(These)S
2484(are)S
2633(implemented)S
3183(as)S
(builtin)262 3292 A
3579(commands.)S
4392 V
1080(The)S
10 I
1262(case)S
10 R
1466(command)S
(looks)217 1887 A
2129(like)S
4632 V
10 B
1480(case)S
10 R
1684(word)S
10 B
1916(in)S
4752 V
10 R
1480(pattern)S
10 B
1760())S
10 R
1819(list)S
10 B
1967(;;)S
4872 V
10 R
(...)75 1480 A
4992 V
10 B
1480(esac)S
5232 V
10 R
1080(The)S
1262(pattern)S
1567(can)S
1732(actually)S
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2366(or)S
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2707(patterns)S
3051((see)S
10 I
3239(Patterns)S
10 R
3605(below),)S
3935(separated)S
4341(by)S
4466(``|'')S
4647(characters.)S
5400 V
1080(Commands)S
1562(may)S
1760(be)S
(grouped)329 1880 A
2234(by)S
(writing)291 2359 A
2675(either)S
5640 V
10 B
1480(()S
10 R
1514(list)S
10 B
1637())S
5880 V
10 R
1080(or)S
6120 V
10 B
1480({)S
10 R
1545(list;)S
10 B
1721(})S
6360 V
10 R
1080(The)S
1262(256rst)S
1444(of)S
1553(these)S
1785(executes)S
2157(the)S
2305(commands)S
2765(in)S
2868(a)S
2938(subshell.)S
6528 V
1080(A)S
1178(function)S
(de256nition)385 1538 A
(looks)217 1948 A
2190(like)S
6768 V
1480(name)S
10 B
1723(()S
1782())S
10 R
1841(command)S
7008 V
1080(A)S
1182(function)S
(de256nition)385 1546 A
1960(is)S
2056(an)S
2180(executable)S
2640(statement;)S
3083(when)S
3330(executed)S
3717(it)S
3802(installs)S
4116(a)S
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4554(named)S
10 B
4851(name)S
10 R
5116(and)S
7128 V
1080(returns)S
1385(an)S
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2475(command)S
2896(is)S
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3376(a)S
3446(list)S
3594(enclosed)S
3971(between)S
4332(``{'')S
4541(and)S
4711(``}''.)S
7296 V
1080(Variables)S
1497(may)S
1700(be)S
1825(declared)S
2197(to)S
2305(be)S
2430(local)S
2656(to)S
2764(a)S
2839(function)S
3205(by)S
3336(using)S
3584(a)S
10 I
3660(local)S
10 R
3892(command.)S
4369(This)S
(should)267 4579 A
4877(appear)S
5177(as)S
7416 V
1080(the)S
1228(256rst)S
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1793(of)S
1902(a)S
1972(function,)S
2357(and)S
(looks)217 2527 A
2769(like)S
7903 V
720(September)S
1176(13,)S
(1996)200 1326 A
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4990(Page)S
5211(2)S
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1480(local)S
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1706([)S
1765(variable)S
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(...)75 2278 A
1200 V
10 I
1080(Local)S
10 R
1334(is)S
1426(implemented)S
1976(as)S
2085(a)S
(builtin)262 2155 A
2442(command.)S
1368 V
1080(When)S
1356(a)S
1438(variable)S
1800(is)S
1904(made)S
2159(local,)S
2417(it)S
2510(inherits)S
2849(the)S
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3281(value)S
3536(and)S
(exported)352 3718 A
4107(and)S
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4678(257ags)S
4905(from)S
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1488 V
1080(variable)S
1439(with)S
1652(the)S
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2050(name)S
2302(in)S
2414(the)S
(surrounding)485 2571 A
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3376(if)S
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3806(one.)S
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4663(variable)S
5021(is)S
5121(ini-)S
1608 V
1080(tially)S
1321(unset.)S
10 I
1617(Ash)S
10 R
1802(uses)S
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2760(so)S
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3068(if)S
(you)150 3164 A
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4436(to)S
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4919(f)S
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1881(g)S
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2725(variable)S
10 B
3086(x)S
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10 I
3699(g)S
10 R
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4834(x)S
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10 R
3934('')S
4028(local)S
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5048(func-)S
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1080(tion)S
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2424 V
1080(The)S
10 I
1262(return)S
10 R
1538(command)S
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2664 V
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1480(return)S
10 R
1786([)S
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3144 V
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10 R
1080(A)S
1182(simple)S
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3552 V
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3792 V
1080(executed.)S
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2758(reverse)S
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4248 V
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5043(made)S
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3905(given)S
4157(in)S
4264(the)S
4416(function)S
(de256nition)385 4780 A
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4728 V
1080(executed.)S
1513(The)S
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2584(are)S
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3186(their)S
3396(original)S
3734(values)S
4016(when)S
4259(the)S
4407(command)S
4828(completes.)S
4896 V
1080(Shell)S
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2581(to)S
2684(the)S
2832(shell,)S
(without)307 3072 A
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3814(a)S
3884(new)S
4077(process.)S
5064 V
1080(When)S
1367(a)S
1459(normal)S
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2179(is)S
2293(executed,)S
2723(the)S
2893(shell)S
3130(runs)S
3350(the)S
3520(program,)S
3934(passing)S
4283(the)S
4454(parameters)S
4945(and)S
5138(the)S
5184 V
1080(environment)S
1616(to)S
1722(the)S
1873(program.)S
2292(If)S
2388(the)S
2539(program)S
2907(is)S
3001(a)S
3073(shell)S
3290(procedure,)S
3745(the)S
3895(shell)S
(will)157 4112 A
4296(interpret)S
4665(the)S
4815(program)S
5183(in)S
5304 V
1080(a)S
1156(subshell.)S
1566(The)S
1754(shell)S
(will)157 1975 A
(reinitialize)432 2163 A
2626(itself)S
2859(in)S
2968(this)S
3144(case,)S
3374(so)S
3494(that)S
3676(the)S
3830(effect)S
(will)157 4092 A
4280(be)S
4407(as)S
4523(if)S
4617(a)S
4694(new)S
4894(shell)S
5116(had)S
5424 V
1080(been)S
(invoked)323 1299 A
1651(to)S
1758(handle)S
2055(the)S
2207(shell)S
2426(procedure,)S
2883(except)S
3175(that)S
3355(the)S
3506(location)S
3858(of)S
3970(commands)S
4433(located)S
4752(in)S
4858(the)S
5009(parent)S
5544 V
1080(shell)S
(will)157 1300 A
1487(be)S
1612(remembered)S
2146(by)S
2276(the)S
2429(child.)S
2710(If)S
2808(the)S
2961(program)S
3332(is)S
3429(a)S
3505(256le)S
3665(beginning)S
4097(with)S
(``#!'',)245 4307 A
4583(the)S
4737(remainder)S
5177(of)S
5664 V
1080(the)S
1233(256rst)S
1420(line)S
1601(speci256es)S
1978(an)S
2103(interpreter)S
2554(for)S
2702(the)S
2855(program.)S
3276(The)S
3463(shell)S
3683((or)S
3831(the)S
3984(operating)S
4394(system,)S
(under)229 4728 A
4986(Berke-)S
5784 V
1080(ley)S
1239(UNIX))S
(will)157 1562 A
1755(run)S
1926(the)S
2086(interpreter)S
2544(in)S
2659(this)S
2841(case.)S
3102(The)S
3296(arguments)S
3752(to)S
3867(the)S
4027(interpreter)S
(will)157 4485 A
4679(consist)S
4995(of)S
5116(any)S
5904 V
1080(arguments)S
1526(given)S
1776(on)S
1903(the)S
2053(256rst)S
2237(line)S
2415(of)S
2526(the)S
2676(program,)S
3069(followed)S
3454(by)S
3581(the)S
3731(name)S
3976(of)S
4087(the)S
4236(program,)S
4628(followed)S
5012(by)S
5138(the)S
6024 V
1080(arguments)S
1524(passed)S
1817(to)S
1920(the)S
2068(program.)S
6264 V
10 B
(Redirection)505 864 A
6432 V
10 R
(Input/output)496 1080 A
1601(redirections)S
2102(can)S
2268(be)S
2389(intermixed)S
2851(with)S
3056(the)S
3205(words)S
3477(in)S
3581(a)S
3652(simple)S
3946(command)S
4368(and)S
4539(can)S
4705(be)S
(placed)263 4826 A
5115(fol-)S
6552 V
1080(lowing)S
1390(any)S
1566(of)S
1681(the)S
1835(other)S
2073(commands.)S
2589(When)S
2860(redirection)S
3328(occurs,)S
3646(the)S
3799(shell)S
4019(saves)S
4267(the)S
4420(old)S
4578(values)S
4865(of)S
4979(the)S
5132(256le)S
6672 V
1080(descriptors)S
1554(and)S
1731(restores)S
2077(them)S
2310(when)S
2560(the)S
2715(command)S
3143(completes.)S
3633(The)S
3822(``<'',)S
4073(``>'',)S
4324(and)S
4502(``>>'')S
4785(redirections)S
6792 V
1080(open)S
1309(a)S
1388(256le)S
1551(for)S
(input,)231 1702 A
1966(output,)S
2280(and)S
2458(appending,)S
2934(respectively.)S
3504(The)S
3694(``<&digit'')S
4182(and)S
4360(``>&digit'')S
4848(makes)S
5138(the)S
6912 V
(input)206 1080 A
1313(or)S
1424(output)S
1707(a)S
(duplicate)369 1779 A
2176(of)S
2288(the)S
2439(256le)S
2596(descriptor)S
3027(numbered)S
3457(by)S
3585(the)S
3736(digit.)S
3998(If)S
4094(a)S
4167(minus)S
4440(sign)S
4635(is)S
4730(used)S
4942(in)S
(place)213 5048 A
7032 V
1080(of)S
1189(a)S
1259(digit,)S
1493(the)S
1641(standard)S
(input)206 2007 A
2238(or)S
2347(standard)S
2713(output)S
2994(are)S
3143(closed.)S
7200 V
1080(The)S
1265(``<<)S
1472(word'')S
1775(redirection)S
2240(takes)S
(input)206 2475 A
2709(from)S
2933(a)S
10 I
3007(here)S
10 R
3215(document.)S
3690(As)S
3831(the)S
3983(shell)S
(encounters)436 4202 A
4667(``<<'')S
4946(redirec-)S
7320 V
1080(tions,)S
1337(it)S
1430(collects)S
1775(them.)S
2063(The)S
2257(next)S
2467(time)S
2682(it)S
(encounters)436 2774 A
3246(an)S
3377(unescaped)S
3832(newline,)S
4212(it)S
4304(reads)S
4553(the)S
4712(documents)S
5183(in)S
7440 V
1080(turn.)S
1321(The)S
1507(word)S
1743(following)S
2163(the)S
2315(``<<'')S
2594(speci256es)S
2970(the)S
3122(contents)S
3486(of)S
3599(the)S
3752(line)S
3933(that)S
4114(terminates)S
4564(the)S
4717(document.)S
5193(If)S
7903 V
720(Page)S
941(3)S
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4455(September)S
4911(13,)S
(1996)200 5061 A
8143 V
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480 V
10 R
720(SH)S
857(()S
899(1)S
957())S
2696(Eighth)S
(Edition)296 2989 A
4990(SH)S
5127(()S
5169(1)S
5227())S
960 V
(none)195 1080 A
1303(of)S
1415(the)S
(quoting)306 1566 A
(methods)340 1900 A
(('',)127 2268 A
2423("",)S
2558(or)S
2670(\))S
2760(are)S
2912(used)S
3124(to)S
3230(enter)S
3460(the)S
3610(word,)S
3869(then)S
4069(the)S
4219(document)S
4642(is)S
4736(treated)S
5038(like)S
5216(a)S
1080 V
1080(word)S
1326(inside)S
(double)273 1605 A
(quotes:)290 1917 A
2271(``$'')S
2496(and)S
(backquote)413 2680 A
3132(are)S
3295(expanded)S
3719(and)S
3904(backslash)S
4335(can)S
4515(be)S
4650(used)S
4874(to)S
4992(escape)S
1200 V
1080(these)S
1316(and)S
1490(to)S
1597(continue)S
(long)178 1972 A
2179(lines.)S
2448(The)S
2634(word)S
(cannot)268 2870 A
3167(contain)S
3492(any)S
3666(variable)S
4020(or)S
4132(command)S
(substitutions,)532 4556 A
5116(and)S
1320 V
1080(its)S
1200(length)S
1476((after)S
(quoting))340 1721 A
2086(must)S
2306(be)S
2426(in)S
2529(the)S
2677(range)S
2926(of)S
3035(1)S
3110(to)S
3214(79)S
3340(characters.)S
3826(If)S
(``<<-'')284 3920 A
4230(is)S
4323(used)S
4533(in)S
(place)213 4637 A
4876(of)S
4986(``<<'',)S
1440 V
1080(then)S
1281(leading)S
1605(tabs)S
1795(are)S
1947(deleted)S
2266(from)S
2490(the)S
2641(lines)S
2859(of)S
2971(the)S
3122(document.)S
3596((This)S
3837(is)S
3932(to)S
4038(allow)S
(you)150 4290 A
4468(do)S
4596(indent)S
4875(shell)S
5093(pro-)S
1560 V
1080(cedures)S
1413(containing)S
1862(here)S
2061(documents)S
2521(in)S
2624(a)S
2694(natural)S
2999(fashion.))S
1728 V
1080(Any)S
1301(of)S
1433(the)S
(preceding)397 1604 A
2049(redirection)S
2534(operators)S
2957(may)S
3178(be)S
(preceded)364 3321 A
3733(by)S
3881(a)S
3974(single)S
4262(digit)S
4494(specifying)S
4961(the)S
5132(256le)S
1848 V
1080(descriptor)S
1524(to)S
1643(be)S
1779(redirected.)S
2274(There)S
(cannot)268 2551 A
2860(be)S
2996(any)S
3182(white)S
(space)224 3447 A
3712(between)S
4089(the)S
4252(digit)S
4476(and)S
4661(the)S
4824(redirection)S
1968 V
1080(operator.)S
2208 V
10 B
864(Path)S
1091(Search)S
2376 V
10 R
1080(When)S
1351(locating)S
1706(a)S
1782(command,)S
2234(the)S
2388(shell)S
2609(256rst)S
(looks)217 2797 A
3045(to)S
3154(see)S
3314(if)S
3407(it)S
3494(has)S
3659(a)S
3735(shell)S
3956(function)S
4322(by)S
4453(that)S
4635(name.)S
4935(Then,)S
5199(if)S
2496 V
1080(PATH)S
1370(does)S
1580(not)S
1734(contain)S
2056(an)S
2177(entry)S
2410(for)S
("%builtin",)453 2554 A
3032(it)S
(looks)217 3113 A
3355(for)S
3498(a)S
(builtin)262 3568 A
3855(command)S
4276(by)S
4401(that)S
4577(name.)S
4870(Finally,)S
5205(it)S
2616 V
1080(searches)S
(each)185 1447 A
1657(entry)S
1889(in)S
1992(PATH)S
2281(in)S
2384(turn)S
2571(for)S
2714(the)S
2862(command.)S
2784 V
1080(The)S
1266(value)S
1513(of)S
1626(the)S
1778(PATH)S
2071(variable)S
(should)267 2425 A
2721(be)S
2845(a)S
2919(series)S
3178(of)S
3292(entries)S
3591(separated)S
4002(by)S
4132(colons.)S
4474(Each)S
4706(entry)S
4943(consists)S
2904 V
1080(of)S
1192(a)S
1265(directory)S
1657(name,)S
1928(or)S
2040(a)S
2113(directory)S
2505(name)S
2751(followed)S
3137(by)S
3265(a)S
3338(257ag)S
3517(beginning)S
3945(with)S
4151(a)S
4223(percent)S
4547(sign.)S
4791(The)S
4975(current)S
3024 V
1080(directory)S
(should)267 1469 A
1761(be)S
1881(indicated)S
2275(by)S
2400(an)S
2520(empty)S
2796(directory)S
3185(name.)S
3192 V
1080(If)S
1177(no)S
1306(percent)S
1632(sign)S
1828(is)S
1924(present,)S
2269(then)S
2471(the)S
2623(entry)S
2859(causes)S
3151(the)S
3303(shell)S
3522(to)S
3629(search)S
3916(for)S
4063(the)S
4216(command)S
4642(in)S
4750(the)S
4903(speci256ed)S
3312 V
1080(directory.)S
1528(If)S
1630(the)S
1787(257ag)S
1972(is)S
(``%builtin'')482 2073 A
2589(then)S
2796(the)S
2953(list)S
3110(of)S
3228(shell)S
(builtin)262 3452 A
3748(commands)S
4217(is)S
4317(searched.)S
4753(If)S
4854(the)S
5010(257ag)S
5194(is)S
3432 V
1080(``%func'')S
1511(then)S
1716(the)S
1871(directory)S
2267(is)S
2366(searched)S
2751(for)S
2901(a)S
2978(256le)S
3139(which)S
3417(is)S
3517(read)S
3724(as)S
(input)206 3841 A
4080(to)S
4191(the)S
4347(shell.)S
4620(This)S
4832(256le)S
(should)267 4994 A
3552 V
1080(de256ne)S
1351(a)S
1421(function)S
1781(whose)S
2063(name)S
2306(is)S
2398(the)S
2546(name)S
2789(of)S
2898(the)S
3046(command)S
3467(being)S
3715(searched)S
4093(for.)S
3720 V
1080(Command)S
1523(names)S
1805(containing)S
2254(a)S
2324(slash)S
2550(are)S
2699(simply)S
2997(executed)S
(without)307 3380 A
3712(performing)S
4190(any)S
4360(of)S
4469(the)S
(above)240 4617 A
4882(searches.)S
3960 V
10 B
864(The)S
1057(Environment)S
4128 V
10 R
1080(The)S
1266(environment)S
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1916(a)S
1990(command)S
2415(is)S
2511(a)S
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2726(of)S
2839(name/value)S
3332(pairs.)S
3607(When)S
3877(the)S
4030(shell)S
4250(is)S
(invoked,)348 4347 A
4725(it)S
4811(reads)S
5054(these)S
4248 V
1080(names)S
1366(and)S
1540(values,)S
1851(sets)S
2031(the)S
2183(shell)S
2402(variables)S
2794(with)S
3001(these)S
3236(names)S
3521(to)S
3627(the)S
(corresponding)575 3778 A
4381(values,)S
4691(and)S
4864(marks)S
5138(the)S
4368 V
1080(variables)S
1469(as)S
(exported.)377 1578 A
2005(The)S
10 I
2187(export)S
10 R
2469(command)S
2890(can)S
3055(be)S
3175(used)S
3384(to)S
3487(mark)S
(additional)402 3719 A
4146(variables)S
4535(as)S
(exported.)377 4644 A
4536 V
1080(The)S
1267(environment)S
1805(of)S
1919(a)S
1995(command)S
2422(is)S
2520(constructed)S
3015(by)S
3146(constructing)S
3674(name/value)S
4169(pairs)S
4396(from)S
4623(all)S
4755(the)S
(exported)352 4909 A
4656 V
1080(shell)S
1295(variables,)S
1709(and)S
1879(then)S
2077(modifying)S
2520(this)S
2690(set)S
2827(by)S
2952(the)S
3100(assignments)S
3616(which)S
(precede)314 3887 A
4226(the)S
4374(command,)S
4820(if)S
4907(any.)S
4896 V
10 B
864(Expansion)S
5064 V
10 R
1080(The)S
1272(process)S
1609(of)S
1728(evaluating)S
2182(words)S
2463(when)S
2716(a)S
2796(shell)S
3021(procedure)S
3459(is)S
3562(executed)S
3956(is)S
4059(called)S
10 I
(expansion)407 4336 A
10 R
4751(.)S
4837(Expansion)S
5184 V
1080(consists)S
1431(of)S
1548(four)S
1748(steps:)S
2034(variable)S
(substitution,)493 2391 A
2916(command)S
(substitution,)493 3344 A
3869(word)S
(splitting,)354 4108 A
4494(and)S
4671(256le)S
4832(name)S
5082(gen-)S
5304 V
1080(eration.)S
1442(If)S
1542(a)S
1619(word)S
1858(is)S
1957(the)S
2112(expression)S
2574(following)S
2998(the)S
3154(word)S
10 B
3394(case)S
10 R
3606(in)S
3717(a)S
3795(case)S
4002(statement,)S
4446(the)S
4602(256le)S
4764(name)S
5015(which)S
5424 V
1080(follows)S
1408(a)S
1479(redirection)S
1942(symbol,)S
2288(or)S
2398(an)S
2519(assignment)S
2997(to)S
3101(the)S
3250(environment)S
3784(of)S
3894(a)S
3965(command,)S
4412(then)S
4611(the)S
4760(word)S
(cannot)268 4993 A
5544 V
1080(be)S
(split)173 1200 A
1398(into)S
(multiple)335 1579 A
1939(words.)S
2260(In)S
2369(these)S
2601(cases,)S
2864(the)S
3012(last)S
3177(two)S
3353(steps)S
3579(of)S
3688(the)S
3836(expansion)S
4268(process)S
4595(are)S
(omitted.)332 4744 A
5784 V
10 B
864(Variable)S
(Substitution)527 1264 A
5952 V
10 R
1080(To)S
1217(be)S
(written.)311 1337 A
6192 V
10 B
864(Command)S
(Substitution)527 1342 A
6360 V
10 I
1080(Ash)S
10 R
(accepts)297 1256 A
1578(two)S
1754(syntaxes)S
2125(for)S
2268(command)S
(substitution:)496 2689 A
6600 V
1480(`)S
10 I
1514(list)S
10 R
1637(`)S
6840 V
1080(and)S
7080 V
1480($()S
10 I
1564(list)S
10 R
1687())S
7320 V
1080(Either)S
1362(of)S
1481(these)S
1723(may)S
1931(be)S
2061(included)S
2442(in)S
2555(a)S
2635(word.)S
2927(During)S
3248(the)S
3407(command)S
(substitution)468 3839 A
4343(process,)S
4706(the)S
4865(command)S
7440 V
1080((syntactly)S
1507(a)S
10 I
1582(list)S
10 R
1713())S
(will)157 1777 A
1964(be)S
2089(executed)S
2477(and)S
2652(anything)S
3033(that)S
3213(the)S
3365(command)S
3790(writes)S
4066(to)S
4173(the)S
4325(standard)S
4695(output)S
(will)157 4980 A
5166(be)S
7903 V
720(September)S
1176(13,)S
(1996)200 1326 A
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4990(Page)S
5211(4)S
8143 V
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4990(SH)S
5127(()S
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5227())S
960 V
1080(captured)S
1452(by)S
1577(the)S
1726(shell.)S
1992(The)S
2175(256nal)S
2380(newline)S
2725((if)S
2847(any))S
3052(of)S
3162(the)S
3311(output)S
(will)157 3593 A
3776(be)S
3897(deleted;)S
4242(the)S
4391(rest)S
4563(of)S
4673(the)S
4822(output)S
(will)157 5104 A
1080 V
1080(be)S
(substituted)435 1200 A
1660(for)S
1803(the)S
1951(command)S
2372(in)S
2475(the)S
2623(word.)S
1320 V
10 B
864(Word)S
1140(Splitting)S
1488 V
10 R
1080(When)S
1350(the)S
1503(value)S
1751(of)S
1865(a)S
1940(variable)S
2295(or)S
2409(the)S
2562(output)S
2848(of)S
2962(a)S
3037(command)S
3463(is)S
(substituted,)460 3560 A
4050(the)S
(resulting)352 4204 A
4587(text)S
4769(is)S
4867(subject)S
5183(to)S
1608 V
1080(word)S
(splitting,)354 1323 A
1713(unless)S
2000(the)S
2159(dollar)S
2430(sign)S
(introducing)463 2633 A
3132(the)S
3291(variable)S
3652(or)S
(backquotes)452 3772 A
4260(containing)S
4720(the)S
4878(text)S
5064(were)S
1728 V
1080(enclosed)S
1459(in)S
(double)273 1564 A
(quotes.)287 1864 A
2203(In)S
(addition,)354 2314 A
2695(``$@'')S
3001(is)S
3095(subject)S
3407(to)S
3512(a)S
3584(special)S
3891(type)S
4091(of)S
(splitting,)354 4202 A
4584(even)S
4802(in)S
4908(the)S
5059(pres-)S
1848 V
1080(ence)S
1290(of)S
(double)273 1399 A
(quotes.)287 1697 A
2016 V
1080(Ash)S
1273(uses)S
1477(two)S
1659(different)S
(splitting)329 2039 A
2400(algorithms.)S
2912(The)S
3101(normal)S
3418(approach,)S
3844(which)S
4122(is)S
4221(intended)S
4599(for)S
(splitting)329 4749 A
5110(text)S
2136 V
1080(separated)S
1487(by)S
1613(which)S
(space,)249 1884 A
2158(is)S
2250(used)S
2459(if)S
2546(the)S
2694(256rst)S
2876(character)S
3272(of)S
3381(the)S
3529(shell)S
3744(variable)S
4094(IFS)S
4265(is)S
4357(a)S
(space.)249 4427 A
4726(Otherwise)S
5166(an)S
2256 V
1080(alternative)S
1537(experimental)S
2094(algorithm,)S
2541(which)S
2818(is)S
2916(useful)S
3193(for)S
(splitting)329 3343 A
3704((possibly)S
4104(empty))S
4421(256elds)S
4671(separated)S
5084(by)S
5216(a)S
2376 V
1080(separator)S
1475(character,)S
1896(is)S
1988(used.)S
2544 V
1080(When)S
1347(performing)S
(splitting,)354 1827 A
2208(the)S
2358(shell)S
2575(scans)S
2820(the)S
(replacement)493 2971 A
3492(text)S
(looking)306 3671 A
4005(for)S
4151(a)S
4224(character)S
4623((when)S
4903(IFS)S
5077(does)S
2664 V
1080(not)S
1244(begin)S
1503(with)S
1718(a)S
(space))258 1799 A
2093(or)S
2213(a)S
2294(sequence)S
2699(of)S
2819(characters)S
3265((when)S
3553(IFS)S
3734(does)S
3953(begin)S
4211(with)S
4425(a)S
(space),)283 4505 A
4823(deletes)S
5138(the)S
2784 V
1080(character)S
1479(or)S
1591(sequence)S
1988(of)S
2100(characters,)S
2563(and)S
2736(spits)S
2948(the)S
3099(word)S
3334(into)S
3518(two)S
3697(strings)S
3993(at)S
4094(that)S
4273(point.)S
4557(When)S
4825(IFS)S
4999(begins)S
2904 V
1080(with)S
1290(a)S
(space,)249 1366 A
1646(the)S
1800(shell)S
2021(deletes)S
2332(either)S
2593(of)S
2708(the)S
2861(strings)S
3159(if)S
3251(they)S
3454(are)S
3608(null.)S
3844(As)S
3986(a)S
4061(special)S
4371(case,)S
4600(if)S
4692(the)S
4845(word)S
5082(con-)S
3024 V
1080(taining)S
1384(the)S
(replacement)493 1532 A
2050(text)S
2226(is)S
2318(the)S
2466(null)S
2647(string,)S
2926(the)S
3074(word)S
3306(is)S
3398(deleted.)S
3192 V
1080(The)S
1266(variable)S
1620(``$@'')S
1928(is)S
2024(special)S
2333(in)S
2440(two)S
2620(ways.)S
2906(First,)S
(splitting)329 3146 A
3505(takes)S
(place)213 3742 A
3985(between)S
4351(the)S
(positional)396 4504 A
4930(parame-)S
3312 V
1080(ters,)S
1281(even)S
1501(if)S
1593(the)S
1746(text)S
1927(is)S
2023(enclosed)S
2404(in)S
(double)273 2511 A
(quotes.)287 2813 A
(Second,)321 3154 A
3504(if)S
3595(the)S
3747(word)S
3983(containing)S
4436(the)S
(replacement)493 4588 A
5110(text)S
3432 V
1080(is)S
1179(the)S
1334(null)S
1522(string)S
1783(and)S
1960(there)S
2194(are)S
2351(no)S
(positional)396 2484 A
2913(parameters,)S
3414(then)S
3620(the)S
3776(word)S
4016(is)S
4116(deleted.)S
4490(The)S
4680(result)S
4937(of)S
5054(these)S
3552 V
1080(rules)S
1309(is)S
1409(that)S
1593("$@")S
1851(is)S
1951(equivalent)S
2403(to)S
2514("$1")S
2729("$2")S
(...)75 2944 A
3052("$)S
10 I
3143(n)S
10 R
3193(",)S
3292(where)S
10 I
3572(n)S
10 R
3655(is)S
3755(the)S
3910(number)S
4249(of)S
(positional)396 4365 A
4793(parameters.)S
3672 V
1080((Note)S
1356(that)S
1553(this)S
1744(differs)S
2054(from)S
2297(the)S
2467(System)S
2810(V)S
2930(shell.)S
3217(The)S
3421(System)S
3764(V)S
3884(documentation)S
4528(claims)S
4838(that)S
5036("$@")S
3792 V
1080(behaves)S
1436(this)S
1613(way;)S
1841(in)S
1951(fact)S
2134(on)S
2265(the)S
2419(System)S
2746(V)S
2850(shell)S
3071("$@")S
3327(is)S
3425(equivalent)S
3875(to)S
3984("")S
4097(when)S
4346(there)S
4579(are)S
4734(no)S
(positional)396 4865 A
3912 V
1080(paramteters.))S
4152 V
10 B
864(File)S
1052(Name)S
1329(Generation)S
4320 V
10 R
1080(Unless)S
1382(the)S
10 B
1533(-f)S
10 R
1629(257ag)S
1808(is)S
1903(set,)S
2068(256le)S
2225(name)S
2471(generation)S
2925(is)S
3021(performed)S
3470(after)S
3685(word)S
(splitting)329 3921 A
4279(is)S
4375(complete.)S
4823(Each)S
5054(word)S
4440 V
1080(is)S
1173(viewed)S
1490(as)S
1600(a)S
1671(series)S
1927(of)S
2036(patterns,)S
2405(separated)S
2811(by)S
2936(slashes.)S
3296(The)S
3478(process)S
3805(of)S
3914(expansion)S
(replaces)331 4346 A
4702(the)S
4850(word)S
5082(with)S
4560 V
1080(the)S
1233(names)S
1520(of)S
1634(all)S
1765(existing)S
2113(256les)S
2311(whose)S
2598(names)S
2885(can)S
3055(be)S
3180(formed)S
3501(by)S
3631(replacing)S
(each)185 4037 A
4253(pattern)S
4564(with)S
4774(a)S
4850(string)S
5110(that)S
4680 V
1080(matches)S
1441(the)S
1595(speci256ed)S
1984(pattern.)S
2345(There)S
2612(are)S
2767(two)S
2949(restrictions)S
3428(on)S
3558(this:)S
3786(256rst,)S
3998(a)S
4073(pattern)S
(cannot)268 4383 A
4681(match)S
4957(a)S
5032(string)S
4800 V
1080(containing)S
1539(a)S
1619(slash,)S
1881(and)S
(second,)304 2062 A
2402(a)S
2483(pattern)S
(cannot)268 2799 A
3103(match)S
3385(a)S
3466(string)S
3731(starting)S
4069(with)S
4284(a)S
4365(period)S
4658(unless)S
4945(the)S
5104(256rst)S
4920 V
1080(character)S
1476(of)S
1585(the)S
1733(pattern)S
2038(is)S
2130(a)S
2200(period.)S
5088 V
1080(If)S
1175(a)S
1247(word)S
1481(fails)S
1682(to)S
1787(match)S
2060(any)S
2232(256les)S
2427(and)S
2599(the)S
10 B
2749(-z)S
10 R
2855(257ag)S
3033(is)S
3127(not)S
3282(set,)S
3446(then)S
3646(the)S
3796(word)S
(will)157 4030 A
4215(be)S
4338(left)S
4501(unchanged)S
4964((except)S
5208 V
1080(that)S
1263(the)S
1418(meta-characters)S
(will)157 2090 A
2279(be)S
(converted)397 2406 A
2835(to)S
2945(normal)S
3262(characters).)S
3787(If)S
3886(the)S
10 B
4040(-z)S
10 R
4150(257ag)S
4332(is)S
4430(set,)S
4598(then)S
4802(the)S
4956(word)S
5194(is)S
5328 V
1080(only)S
1290(left)S
1458(unchanged)S
1926(if)S
(none)195 2021 A
2249(of)S
2366(the)S
2522(patterns)S
2874(contain)S
3203(a)S
3281(character)S
3685(that)S
3869(can)S
4042(match)S
4321(anything)S
4705(besides)S
5034(itself.)S
5448 V
1080(Otherwise)S
1524(the)S
10 B
1676(-z)S
10 R
1784(257ag)S
1964(forces)S
2240(the)S
2392(word)S
2628(to)S
2735(be)S
(replaced)342 2859 A
3230(with)S
3438(the)S
3590(names)S
3876(of)S
3988(the)S
4139(256les)S
4335(that)S
4514(it)S
4598(matches,)S
4981(even)S
5199(if)S
5568 V
1080(there)S
1307(are)S
1456(zero)S
1655(names.)S
5808 V
10 B
864(Patterns)S
5976 V
10 R
1080(A)S
10 I
1195(pattern)S
10 R
1527(consists)S
1887(of)S
2013(normal)S
2340(characters,)S
2817(which)S
3106(match)S
3395(themselves,)S
3910(and)S
4098(meta-characters.)S
4831(The)S
5031(meta-)S
6096 V
1080(characters)S
1533(are)S
(``!'',)195 1699 A
1936(``*'',)S
2189(``?'',)S
2437(and)S
(``[''.)195 2624 A
2886(These)S
3169(characters)S
3621(lose)S
3825(there)S
4069(special)S
4391(meanings)S
4818(if)S
4922(they)S
5137(are)S
6216 V
(quoted.)298 1080 A
1428(When)S
1693(command)S
2114(or)S
2223(variable)S
(substitution)468 2573 A
3066(is)S
3158(performed)S
3603(and)S
3773(the)S
3921(dollar)S
4181(sign)S
4373(or)S
4482(back)S
(quotes)262 4697 A
4984(are)S
5133(not)S
6336 V
(double)273 1080 A
(quoted,)298 1386 A
1716(the)S
1871(value)S
2121(of)S
2237(the)S
2392(variable)S
2749(or)S
2865(the)S
3020(output)S
3308(of)S
3424(the)S
3579(command)S
4007(is)S
4106(scanned)S
4462(for)S
4612(these)S
4851(characters)S
6456 V
1080(and)S
1250(they)S
1448(are)S
1597(turned)S
1879(into)S
2060(meta-characters.)S
6624 V
1080(Two)S
1293(exclamation)S
1813(points)S
2086(at)S
2187(the)S
2338(beginning)S
2767(of)S
2879(a)S
2952(pattern)S
3260(function)S
3623(as)S
3736(a)S
3810(``not'')S
4103(operator,)S
4493(causing)S
4829(the)S
4981(pattern)S
6744 V
1080(to)S
1187(match)S
1462(any)S
1636(string)S
1893(that)S
2072(the)S
2223(remainder)S
2660(of)S
2772(the)S
2923(pattern)S
3231(does)S
10 I
3443(not)S
10 R
3599(match.)S
3923(Other)S
4181(occurances)S
4657(of)S
4769(exclamation)S
6864 V
1080(points)S
1357(in)S
1467(a)S
1544(pattern)S
1856(match)S
2134(exclamation)S
2658(points.)S
2985(Two)S
3202(exclamation)S
3726(points)S
4004(are)S
4161(required)S
4530(rather)S
4799(than)S
5005(one)S
5183(to)S
6984 V
1080(decrease)S
1468(the)S
(incompatibility)614 1631 A
2285(with)S
2504(the)S
2667(System)S
3003(V)S
3116(shell)S
3346((which)S
3666(does)S
3890(not)S
4058(treat)S
4278(exclamation)S
4809(points)S
5093(spe-)S
7104 V
1080(cially).)S
7272 V
1080(An)S
1230(asterisk)S
((``*''))254 1566 A
1848(matches)S
2206(any)S
2379(string)S
2636(of)S
2748(characters.)S
3236(A)S
3337(question)S
3705(mark)S
3940(matches)S
4298(any)S
4471(single)S
4739(character.)S
5188(A)S
7392 V
1080(left)S
1244(bracket)S
((``[''))238 1570 A
(introduces)419 1837 A
2285(a)S
2359(character)S
2759(class.)S
3034(The)S
3220(end)S
3394(of)S
3506(the)S
3657(character)S
4056(class)S
4280(is)S
4375(indicated)S
4772(by)S
4900(a)S
(``]'';)198 4973 A
5199(if)S
7512 V
1080(the)S
(``]'')170 1233 A
1433(is)S
1530(missing)S
1872(then)S
2075(the)S
(``['')170 2228 A
2428(matches)S
2789(a)S
(``['')170 2865 A
3066(rather)S
3333(than)S
(introducing)463 3537 A
4031(a)S
4107(character)S
4509(class.)S
4786(A)S
4890(character)S
7903 V
720(Page)S
941(5)S
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4455(September)S
4911(13,)S
(1996)200 5061 A
8143 V
EP
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/slant 0 def
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480 V
10 R
720(SH)S
857(()S
899(1)S
957())S
2696(Eighth)S
(Edition)296 2989 A
4990(SH)S
5127(()S
5169(1)S
5227())S
960 V
1080(class)S
1325(matches)S
1704(any)S
1898(of)S
2031(the)S
2203(characters)S
2662(between)S
3046(the)S
3217(square)S
3528(brackets.)S
3962(A)S
4083(range)S
4355(of)S
4487(characters)S
4945(may)S
5166(be)S
1080 V
1080(speci256ed)S
1475(using)S
1729(a)S
1811(minus)S
2093(sign.)S
2347(The)S
2542(character)S
2951(class)S
3185(may)S
3396(be)S
3529(complemented)S
4159(by)S
4297(making)S
4636(an)S
4769(exclamation)S
1200 V
1080(point)S
1311(the)S
1459(256rst)S
1641(character)S
2037(of)S
2146(the)S
2294(character)S
2690(class.)S
1368 V
1080(To)S
1231(include)S
1567(a)S
(``]'')170 1652 A
1862(in)S
1980(a)S
2065(character)S
2476(class,)S
2737(make)S
2995(it)S
3091(the)S
3254(256rst)S
3451(character)S
3862(listed)S
4120((after)S
4380(the)S
(``!'',)195 4543 A
4778(if)S
4880(any).)S
5149(To)S
1488 V
1080(include)S
1401(a)S
1471(minus)S
1741(sign,)S
1958(make)S
2201(it)S
2282(the)S
2430(256rst)S
2612(or)S
2721(last)S
2886(character)S
3282(listed.)S
1728 V
10 B
864(The)S
1057(/u)S
(Directory)415 1166 A
1896 V
10 R
1080(By)S
(convention,)471 1227 A
1728(the)S
1881(name)S
(``/u/user'')410 2129 A
2569(refers)S
2830(to)S
2938(the)S
3091(home)S
3344(directory)S
3738(of)S
3852(the)S
4005(speci256ed)S
4393(user.)S
4641(There)S
4907(are)S
(good)200 5061 A
2016 V
1080(reasons)S
1409(why)S
1609(this)S
1781(feature)S
(should)267 2089 A
2383(be)S
(supported)396 2505 A
2928(by)S
3054(the)S
3203(256le)S
3358(system)S
3663((using)S
3940(a)S
4011(feature)S
4318(such)S
4528(as)S
4638(symbolic)S
5032(links))S
2136 V
1080(rather)S
1343(than)S
1543(by)S
1670(the)S
1821(shell,)S
2064(but)S
10 I
2220(ash)S
10 R
2387(is)S
2482(capable)S
2818(of)S
2930(performing)S
3411(this)S
3584(mapping)S
3963(if)S
4053(the)S
4204(256le)S
4361(system)S
4668(doesn't.)S
5042(If)S
5138(the)S
2256 V
1080(mapping)S
1456(is)S
(done)195 1548 A
1768(by)S
10 I
1893(ash)S
10 R
2040(,)S
(setting)268 2090 A
2383(the)S
10 B
2531(-f)S
10 R
2624(257ag)S
(will)157 2800 A
2982(turn)S
3169(it)S
3250(off.)S
2496 V
10 B
864(Character)S
1332(Set)S
2664 V
10 I
1080(Ash)S
10 R
1265(silently)S
1595(discards)S
1959(nul)S
2121(characters.)S
2615(Any)S
2823(other)S
3065(character)S
(will)157 3471 A
3663(be)S
3793(handled)S
4146(correctly)S
4540(by)S
10 I
4675(ash)S
10 R
4822(,)S
4882(including)S
2784 V
1080(characters)S
1515(with)S
1719(the)S
1867(high)S
2070(order)S
2308(bit)S
2439(set.)S
3024 V
10 B
864(Job)S
1045(Names)S
1361(and)S
1548(Job)S
1729(Control)S
3192 V
10 R
1080(The)S
1267(term)S
10 I
1482(job)S
10 R
1640(refers)S
1901(to)S
2009(a)S
2084(process)S
2416(created)S
2738(by)S
2868(a)S
2944(shell)S
3165(command,)S
3617(or)S
3732(in)S
3841(the)S
3995(case)S
4200(of)S
4315(a)S
4391(pipeline,)S
4771(to)S
4880(the)S
5034(set)S
5177(of)S
3312 V
1080(processes)S
1491(in)S
1594(the)S
1742(pipeline.)S
2141(The)S
2323(ways)S
2555(to)S
2658(refer)S
2875(to)S
2978(a)S
3048(job)S
3201(are:)S
3552 V
1480(%)S
10 I
1564(number)S
3672 V
10 R
1480(%)S
10 I
1564(string)S
3792 V
10 R
1480(%%)S
3912 V
10 I
1480(process_id)S
4152 V
10 R
1080(The)S
1262(256rst)S
1444(form)S
1665(identi256es)S
2059(a)S
2129(job)S
2283(by)S
2409(job)S
2563(number.)S
2946(When)S
3212(a)S
3283(command)S
3705(is)S
3798(run,)S
10 I
3983(ash)S
10 R
4148(assigns)S
4464(it)S
4546(a)S
4617(job)S
4771(number)S
5104((the)S
4272 V
1080(lowest)S
(unused)284 1379 A
1699(number)S
2042(is)S
2145(assigned).)S
2611(The)S
(second)279 2804 A
3119(form)S
3351(identi256es)S
3756(a)S
3837(job)S
4001(by)S
4136(giving)S
4427(a)S
4507(pre256x)S
4777(of)S
4896(the)S
5054(com-)S
4392 V
1080(mand)S
1335(used)S
1551(to)S
1661(create)S
1935(the)S
2090(job.)S
2300(The)S
2489(pre256x)S
2756(must)S
2983(be)S
3110(unique.)S
3465(If)S
3565(there)S
3800(is)S
3900(only)S
4111(one)S
4289(job,)S
4475(then)S
4681(the)S
4837(null)S
5026(pre256x)S
4512 V
(will)157 1080 A
1268(identify)S
1612(the)S
1766(job,)S
1949(so)S
(you)150 2068 A
2248(can)S
2418(refer)S
2640(to)S
2748(the)S
2901(job)S
3059(by)S
(writing)291 3189 A
3510(``%''.)S
3810(The)S
3997(third)S
4217(form)S
4443(refers)S
4704(to)S
4812(the)S
10 I
4965(current)S
4632 V
1080(job)S
10 R
1208(.)S
1291(The)S
1481(current)S
1800(job)S
1961(is)S
2061(the)S
2217(last)S
2390(job)S
2551(to)S
2662(be)S
(stopped)312 2790 A
3136(while)S
3394(it)S
3484(was)S
3675(in)S
3787(the)S
(foreground.)472 3944 A
4475((See)S
4689(the)S
4846(next)S
5053(para-)S
4752 V
1080(graph.))S
1418(The)S
1600(last)S
1765(form)S
1986(identi256es)S
2380(a)S
2450(job)S
2603(by)S
2728(giving)S
3009(the)S
3157(process)S
3484(id)S
3587(of)S
3696(the)S
3844(last)S
4009(process)S
4336(in)S
4439(the)S
4587(job.)S
4920 V
1080(If)S
1176(the)S
1327(operating)S
1735(system)S
2042(that)S
10 I
2221(ash)S
10 R
2388(is)S
(running)312 2483 A
2823(on)S
(supports)340 2951 A
3319(job)S
3475(control,)S
10 I
3813(ash)S
10 R
(will)157 3980 A
4166(allow)S
(you)150 4419 A
4598(to)S
4705(use)S
4868(it.)S
5003(In)S
5116(this)S
5040 V
1080(case,)S
1311(typing)S
1599(the)S
1754(suspend)S
2109(character)S
2512((typically)S
2930(303Z))S
3092(while)S
(running)312 3348 A
3692(a)S
3769(command)S
(will)157 4196 A
4384(return)S
(you)150 4656 A
4837(to)S
10 I
4946(ash)S
10 R
5116(and)S
5160 V
(will)157 1080 A
1269(make)S
1519(the)S
1674(suspended)S
2124(command)S
2553(the)S
2709(current)S
3028(job.)S
3239(You)S
3445(can)S
3618(then)S
3824(continue)S
4203(the)S
4359(job)S
4520(in)S
4631(the)S
(background)474 4787 A
5280 V
1080(by)S
1205(typing)S
10 I
1486(bg)S
10 R
1594(,)S
1644(or)S
(you)150 1753 A
1928(can)S
2093(continue)S
2464(it)S
2545(in)S
2648(the)S
(foreground)447 2796 A
3268(by)S
3393(typing)S
10 I
3674(fg)S
10 R
3760(.)S
5520 V
10 B
864(Atty)S
5688 V
10 R
1080(If)S
1182(the)S
1339(shell)S
1563(variable)S
1922(ATTY)S
2226(is)S
2327(set,)S
2498(and)S
2677(the)S
2834(shell)S
3058(variable)S
3417(TERM)S
3731(is)S
3832(not)S
3994(set)S
4140(to)S
4252(``emacs'',)S
4700(then)S
10 I
4908(ash)S
10 R
5082(gen-)S
5808 V
1080(erates)S
1341(appropriate)S
1825(escape)S
2119(sequences)S
2552(to)S
2655(talk)S
2831(to)S
10 I
2934(atty)S
10 R
3093((1).)S
6048 V
10 B
864(Exit)S
1068(Statuses)S
6216 V
10 R
1080(By)S
(tradition,)366 1223 A
1615(an)S
1737(exit)S
1915(status)S
2171(of)S
2282(zero)S
2483(means)S
2767(that)S
2945(a)S
3017(command)S
3440(has)S
(succeeded)414 3601 A
4042(and)S
4214(a)S
(nonzero)324 4286 A
4637(exit)S
4815(status)S
5071(indi-)S
6336 V
1080(cates)S
1315(that)S
1499(the)S
1655(command)S
2084(failed.)S
2397(This)S
2609(is)S
2709(better)S
2971(than)S
3176(no)S
(convention)446 3308 A
3786(at)S
3891(all,)S
4049(but)S
4209(in)S
4319(practice)S
4671(it)S
4759(is)S
4858(extremely)S
6456 V
1080(useful)S
1365(to)S
1482(allow)S
1745(commands)S
2219(that)S
(succeed)319 2409 A
2767(to)S
2884(use)S
3057(the)S
3219(exit)S
3409(status)S
3678(to)S
3796(return)S
4077(information)S
4592(to)S
4710(the)S
4873(caller.)S
5188(A)S
6576 V
1080(variety)S
1395(of)S
1513(better)S
(conventions)485 1777 A
2296(have)S
2520(been)S
(proposed,)393 2744 A
3171(but)S
(none)195 3333 A
3562(of)S
3680(them)S
3915(has)S
4083(met)S
4268(with)S
4481(universal)S
4884(approval.)S
6696 V
1080(The)S
(convention)446 1262 A
1733(used)S
1942(by)S
10 I
2067(ash)S
10 R
2231(and)S
2401(all)S
2527(the)S
2675(programs)S
3080(included)S
3451(in)S
3554(the)S
10 I
3702(ash)S
10 R
3866(distribution)S
4354(is)S
4446(as)S
4555(follows:)S
6816 V
1800(0)S
(Success.)344 2520 A
6936 V
1800(1)S
2520(Alternate)S
(success.)327 2921 A
7056 V
1800(2)S
2520(Failure.)S
7176 V
(129-...)259 1800 A
2520(Command)S
2963(terminated)S
3419(by)S
3544(a)S
3614(signal.)S
7296 V
1080(The)S
10 I
1269(alternate)S
(success)302 1664 A
10 R
1998(return)S
2271(is)S
2370(used)S
2586(by)S
2718(commands)S
3185(to)S
3296(indicate)S
3648(various)S
(conditions)418 3977 A
4428(which)S
4707(are)S
4864(not)S
5025(errors)S
7416 V
1080(but)S
1248(which)S
1534(can,)S
1738(with)S
1956(a)S
(little)185 2040 A
2264(imagination,)S
2808(be)S
2942(conceived)S
3389(of)S
3512(as)S
3635(less)S
(successful)414 3825 A
4278(than)S
4490(plain)S
(success.)327 4730 A
5121(For)S
7536 V
1080(example,)S
10 I
1474(test)S
10 R
1642(returns)S
1950(1)S
2028(when)S
2274(the)S
2425(tested)S
(condition)379 2689 A
3097(is)S
3193(false)S
3413(and)S
10 I
3587(getopts)S
10 R
3906(returns)S
4215(1)S
4294(when)S
4541(there)S
4772(are)S
4925(no)S
5054(more)S
7903 V
720(September)S
1176(13,)S
(1996)200 1326 A
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4990(Page)S
5211(6)S
8143 V
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480 V
10 R
720(SH)S
857(()S
899(1)S
957())S
2696(Eighth)S
(Edition)296 2989 A
4990(SH)S
5127(()S
5169(1)S
5227())S
960 V
1080(options.)S
(Because)336 1459 A
1829(this)S
(convention)446 2008 A
2488(is)S
2589(not)S
2751(used)S
2969(universally,)S
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10 B
3632(-e)S
10 R
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4035(of)S
10 I
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10 R
4324(causes)S
4620(the)S
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1080 V
1080(when)S
1323(a)S
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1814(returns)S
2119(1)S
2194(even)S
(though)278 2409 A
2712(that)S
2888(contradicts)S
3355(the)S
(convention)446 3503 A
3974(described)S
4385(here.)S
1248 V
1080(When)S
1346(a)S
1417(command)S
1839(is)S
1932(terminated)S
2389(by)S
2515(a)S
2586(signal,)S
2877(the)S
3026(uses)S
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3401(plus)S
3594(the)S
3743(signal)S
4009(number)S
4342(as)S
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1368 V
1080(command.)S
1608 V
10 B
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1776 V
10 R
1080(This)S
1299(concluding)S
1785(section)S
2111(lists)S
2314(the)S
(builtin)262 2478 A
2781(commands)S
3257(which)S
3544(are)S
(builtin)262 3709 A
(because)319 4012 A
4372(they)S
4586(need)S
4817(to)S
4936(perform)S
1896 V
1080(some)S
1327(operation)S
1742(that)S
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2750(by)S
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3331(process.)S
3718(In)S
(addition)329 3837 A
4201(to)S
4314(these,)S
4581(there)S
4817(are)S
4975(several)S
2016 V
1080(other)S
1314(commands)S
1776(()S
10 I
1810(catf)S
10 R
1969(,)S
10 I
2021(echo)S
10 R
2219(,)S
10 I
2271(expr)S
10 R
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10 I
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10 R
2669(,)S
10 I
2721(nlecho)S
10 R
2997(,)S
10 I
3050(test)S
10 R
3198(,)S
3251(``)S
10 I
3319(:)S
10 R
3361('',)S
3482(and)S
10 I
3655(true)S
10 R
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3887(which)S
4161(can)S
4329(optionally)S
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4887(compiled)S
2136 V
1080(into)S
1267(the)S
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2170(commands)S
2635(described)S
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(accept)258 3508 A
3796(options)S
4121(use)S
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4867(Release)S
5211(2)S
2256 V
10 I
1080(getopt)S
10 R
1339((3))S
1482(syntax.)S
2544 V
10 B
1080(bg)S
10 R
1211([)S
10 I
1270(job)S
10 R
1423(])S
(...)75 1482 A
2664 V
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2172(jobs)S
2370((or)S
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2992(job)S
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3246(no)S
3378(jobs)S
3577(are)S
3733(given))S
4022(in)S
4132(the)S
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4843(This)S
5054(com-)S
2784 V
1230(mand)S
1478(is)S
1570(only)S
1773(available)S
2162(on)S
2287(systems)S
2630(with)S
2834(Bekeley)S
3189(job)S
3342(control.)S
2952 V
10 B
1080(command)S
10 I
(command)391 1530 A
1946(arg)S
10 R
(...)75 2093 A
3072 V
1230(Execute)S
1592(the)S
1752(speci256ed)S
(builtin)262 2147 A
2446(command.)S
2929((This)S
3179(is)S
3283(useful)S
3566(when)S
(you)150 3821 A
4009(have)S
4237(a)S
4320(shell)S
4548(function)S
4921(with)S
5138(the)S
3192 V
1230(same)S
1462(name)S
1705(as)S
1814(a)S
(builtin)262 1884 A
2171(command.))S
3360 V
10 B
1080(cd)S
10 R
1206([)S
10 I
1265(directory)S
10 R
1659(])S
3480 V
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2618((default)S
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4078(for)S
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5022(in)S
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3868(is)S
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4107(and)S
4282(the)S
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4829(name)S
5077(does)S
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2589(directories)S
3053(listed)S
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4062(be)S
4195(searched)S
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5006(the)S
5166(cd)S
3960 V
1230(command)S
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1835(print)S
2051(out)S
2205(the)S
2354(name)S
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4080 V
1230(the)S
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4616(mechanism)S
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4200 V
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1439(or)S
(because)319 1548 A
1892(a)S
1962(symbolic)S
2355(link)S
2536(was)S
2718(crossed.)S
4368 V
10 B
1080(.)S
10 I
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4488 V
10 R
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1414(commands)S
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1981(the)S
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3708(the)S
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4125(A)S
4225(path)S
4425(search)S
4710(is)S
4804(not)S
(done)195 4960 A
5183(to)S
4608 V
1230(256nd)S
1424(the)S
1585(256le)S
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2109(the)S
2270(directories)S
2734(in)S
2850(PATH)S
3152(generally)S
3565(contain)S
3899(256les)S
4105(that)S
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4840(to)S
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5087(exe-)S
4728 V
1230(cuted,)S
1498(not)S
1651(read.)S
4896 V
10 B
1080(eval)S
10 I
1278(string)S
10 R
(...)75 1520 A
5016 V
1230(The)S
1425(strings)S
1731(are)S
1893(parsed)S
2194(as)S
2316(shell)S
2544(commands)S
3017(and)S
3200(executed.)S
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3899(differs)S
4202(from)S
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4934(V)S
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5136 V
1230(which)S
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2243(arguments)S
2705((separated)S
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4128(the)S
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4685(a)S
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5054(com-)S
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1230(mand.))S
5424 V
10 B
1080(exec)S
10 R
1290([)S
10 I
(command)391 1349 A
1765(arg)S
10 R
(...)75 1912 A
2037(])S
5544 V
1230(Unless)S
10 I
(command)391 1537 A
10 R
1961(is)S
(omitted,)332 2061 A
2426(the)S
2582(shell)S
2805(process)S
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3615(with)S
3828(the)S
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3436(Any)S
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4169(on)S
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5054(com-)S
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1230(mand)S
1478(is)S
1570(not)S
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2007(the)S
2155(exec)S
2365(command)S
2786(causes)S
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6072 V
10 B
1080(exit)S
10 R
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10 I
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3897(function)S
4269(is)S
4373(terminated,)S
4866(no)S
5003(matter)S
1080 V
1080(how)S
1278(it)S
1359(is)S
1451(terminated.)S
1248 V
9 R
720(H)S
722(HI)S
790(IN)S
823(NT)S
891(TS)S
949(S)S
1368 V
10 R
1080(Shell)S
1318(variables)S
1713(can)S
1884(be)S
2010(used)S
2226(to)S
2336(provide)S
2675(abbreviations)S
3249(for)S
3399(things)S
3676(which)S
(you)150 3954 A
4136(type)S
4341(frequently.)S
4837(For)S
5009(exam-)S
1488 V
1080(ple,)S
1253(I)S
1312(set)S
1608 V
(export)257 1800 A
2082(h=$HOME)S
1728 V
1080(in)S
1183(my)S
1336(.pro256le)S
1649(so)S
1763(that)S
1939(I)S
1998(can)S
2163(type)S
2361(the)S
2509(name)S
2752(of)S
2861(my)S
3014(home)S
3262(directory)S
3651(simply)S
3949(by)S
4074(typing)S
4355(``$h''.)S
1896 V
1080(When)S
(writing)291 1350 A
1671(shell)S
1891(procedures,)S
2388(try)S
2530(not)S
2688(to)S
2796(make)S
3044(assumptions)S
(about)223 3570 A
3823(what)S
4049(is)S
4146(imported)S
4539(from)S
4766(the)S
4920(environ-)S
2016 V
1080(ment.)S
(Explicitly)397 1358 A
1782(unset)S
2021(or)S
(initialize)353 2132 A
2512(all)S
2639(variables,)S
3054(rather)S
3316(than)S
3515(assuming)S
3920(they)S
(will)157 4119 A
4302(be)S
4423(unset.)S
4711(If)S
(you)150 4805 A
4981(use)S
5141(cd,)S
2136 V
1080(it)S
1161(is)S
1253(a)S
(good)200 1323 A
1548(idea)S
1741(to)S
1844(unset)S
2081(CDPATH.)S
2304 V
1080(People)S
1379(sometimes)S
1834(use)S
(``<&-'')305 1993 A
2323(or)S
(``>&-'')305 2432 A
2762(to)S
2865(provide)S
3197(no)S
(input)206 3322 A
3553(to)S
3656(a)S
3726(command)S
4147(or)S
4256(to)S
4359(discard)S
4675(the)S
4824(output)S
5106(of)S
5216(a)S
2424 V
1080(command.)S
1551(A)S
1649(better)S
1904(way)S
2097(to)S
2200(do)S
2325(this)S
2495(is)S
2587(to)S
2690(redirect)S
3024(the)S
(input)206 3172 A
3403(or)S
3512(output)S
3793(of)S
3902(the)S
4050(command)S
4471(to)S
10 B
4574(/dev/null)S
10 R
4949(.)S
2592 V
1080(Word)S
(splitting)329 1334 A
1688(and)S
1858(256le)S
2012(name)S
2255(generation)S
2705(are)S
2854(performed)S
3299(by)S
3424(default,)S
3755(and)S
(you)150 3926 A
4102(have)S
4318(to)S
(explicitly)380 4422 A
4828(use)S
(double)273 4988 A
2712 V
(quotes)262 1080 A
1371(to)S
(suppress)346 1478 A
1853(it.)S
1987(This)S
2194(is)S
2289(backwards,)S
2773(but)S
(you)150 2929 A
3107(can)S
3275(learn)S
3505(to)S
3611(live)S
3790(with)S
3997(it.)S
4131(Just)S
4315(get)S
4466(in)S
4572(the)S
4723(habit)S
4952(of)S
5064(writ-)S
2832 V
1080(ing)S
(double)273 1246 A
(quotes)262 1557 A
(around)279 1857 A
2174(variable)S
2537(and)S
2720(command)S
(substitutions,)532 3154 A
3724(and)S
3907(omit)S
4129(them)S
4368(only)S
4585(when)S
(you)150 4842 A
5031(really)S
2952 V
1080(want)S
1306(word)S
(splitting)329 1543 A
1902(and)S
2077(256le)S
2236(name)S
2484(generation.)S
2989(If)S
(you)150 3087 A
3267(want)S
3493(word)S
(splitting)329 3730 A
4089(but)S
4247(not)S
4405(256le)S
4564(name)S
4811(generation,)S
3072 V
1080(use)S
1239(the)S
10 B
1387(-f)S
10 R
1480(option.)S
3240 V
9 R
720(A)S
722(AU)S
790(UT)S
858(TH)S
916(HO)S
984(OR)S
1052(RS)S
1114(S)S
3360 V
10 R
1080(Kenneth)S
1446(Almquist)S
3528 V
9 R
720(S)S
722(SE)S
774(EE)S
832(E)S
913(A)S
915(AL)S
983(LS)S
1041(SO)S
1093(O)S
3648 V
10 R
1080(echo(1),)S
1438(expr(1),)S
1785(line(1),)S
2104(pwd(1),)S
2445(true(1).)S
3816 V
9 R
720(B)S
722(BU)S
784(UG)S
852(GS)S
920(S)S
3936 V
10 R
1080(When)S
1354(command)S
(substitution)468 1784 A
2286(occurs)S
2583(inside)S
2857(a)S
2936(here)S
3144(document,)S
3599(the)S
3756(commands)S
4225(inside)S
4499(the)S
4656(here)S
4865(document)S
4056 V
1080(are)S
1230(run)S
1390(with)S
1595(their)S
1806(standard)S
(input)206 2173 A
2405(closed.)S
2738(For)S
2904(example,)S
3296(the)S
3445(following)S
(will)157 3861 A
4043(not)S
4196(word)S
(because)319 4428 A
4772(the)S
4920(standard)S
4176 V
(input)206 1080 A
1311(of)S
1420(the)S
10 I
1568(line)S
10 R
1744(command)S
(will)157 2165 A
2347(be)S
2467(closed)S
2749(when)S
2992(the)S
3140(command)S
3561(is)S
3653(run:)S
4416 V
1480(cat)S
1623(<<-!)S
4536 V
1480(Line)S
1690(1:)S
1793($(line))S
4656 V
1480(Line)S
1690(2:)S
1793($(line))S
4776 V
1480(!)S
5064 V
(Unsetting)391 1080 A
1496(a)S
1566(function)S
1926(which)S
2197(is)S
2289(currently)S
2678(being)S
2926(executed)S
3309(may)S
3507(cause)S
3756(strange)S
4072(behavior.)S
5232 V
1080(The)S
1264(shell)S
1481(syntax)S
1770(allows)S
2060(a)S
2132(here)S
2333(document)S
2756(to)S
2861(be)S
2983(terminated)S
3441(by)S
3568(an)S
3690(end)S
3862(of)S
3973(256le)S
4129(as)S
4240(well)S
4441(as)S
4552(by)S
4679(a)S
4752(line)S
4931(contain-)S
5352 V
1080(ing)S
1238(the)S
1391(terminator)S
1841(word)S
2078(which)S
2354(follows)S
2686(the)S
2838(``<<''.)S
3167(What)S
3414(this)S
3588(means)S
3874(is)S
3970(that)S
4150(if)S
(you)150 4241 A
4420(mistype)S
4767(the)S
4919(termina-)S
5472 V
1080(tor)S
1217(line,)S
1418(the)S
1566(shell)S
(will)157 1781 A
1963(silently)S
2284(swallow)S
2645(up)S
2770(the)S
2918(rest)S
3089(of)S
(your)184 3198 A
3407(shell)S
3622(script)S
3871(and)S
4041(stick)S
4256(it)S
4337(in)S
4440(the)S
4588(here)S
4787(document.)S
7903 V
720(Page)S
941(11)S
2654(()S
2696(March)S
2984(7,)S
(1991)200 3084 A
3292())S
4455(September)S
4911(13,)S
(1996)200 5061 A
8143 V
EP
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