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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/Palatino-Roman@0 SF
(\207Morris Bolsky and David Korn,)72 708 Q/F5 8/Palatino-Italic@0 SF
(The KornShell Command and Pr)2 E(ogramming Language)-.144 E F4 2(,P)C -.144
(re)374.688 708 S(ntice Hall, 1989.).144 E EP
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/F0 10/Palatino-Roman@0 SF 2.5(-3-)279.67 48 S .953
(For interactive use, Bash implements ksh-style aliases and builtins such as)72
84 R/F1 10/Palatino-Bold@0 SF(fc)3.453 E F0 .953(\(discussed below\))3.453 F
(and)72 96 Q F1(jobs)2.603 E F0 5.103(.B)C .104
(ash aliases allow a string to be substituted for a command name.)124.686 96 R
.104(They can be used to)5.104 F(cr)72 108 Q .936(eate a mnemonic for a)-.18 F
/F2 9/Palatino-Roman@0 SF(UNIX)3.435 E F0 .935(command name \()3.435 F/F3 10
/Courier@0 SF .935(alias del=rm)B F0 .935(\), to expand a single wor)B 3.435
(dt)-.18 G 3.435(oa)490.105 108 S 1.465(complex command \()72 120 R F3 1.465
(alias news='xterm -g 80x45 -title trn -e trn -e -S1 -N)B(&')72 132 Q F0 .738
(\), or to ensur)B 3.238(et)-.18 G .737
(hat a command is invoked with a basic set of options \()153.612 132 R F3 .737
(alias ls="/bin/ls)B(-F")72 144 Q F0(\).)A .4(The C shell \()97 159.6 R F1(csh)
A F0 .401(\)\207, originally written by Bill Joy while at Berkeley)B 2.901(,i)
-1.11 G 2.901(sw)396.846 159.6 S .401(idely used and quite)412.327 159.6 R .002
(popular for its interactive facilities.)72 171.6 R .002
(Bash includes a csh-compatible history expansion mechanism)5.002 F(\(`)72
183.6 Q 2.058(`! history')-.37 F 2.058
('\), brace expansion, access to a stack of dir)-.37 F 2.058(ectories via the)
-.18 F F1(pushd)4.558 E F0(,)A F1(popd)4.558 E F0 4.558(,a)C(nd)469.742 183.6 Q
F1(dirs)4.558 E F0 .648
(builtins, and tilde expansion, to generate users' home dir)72 195.6 R 3.148
(ectories. T)-.18 F .647(ilde expansion has also been)-.55 F
(adopted by both the Korn Shell and POSIX.2.)72 207.6 Q(Ther)97 223.2 Q 2.98
(ew)-.18 G(er)133.62 223.2 Q 2.98(ec)-.18 G .48(ertain ar)154.39 223.2 R .48
(eas in which POSIX.2 felt standar)-.18 F .48(dization was necessary)-.18 F
2.98(,b)-1.11 G .48(ut no exist-)453.78 223.2 R 1.061(ing implementation pr)72
235.2 R 1.062(ovided the pr)-.18 F 1.062(oper behavior)-.18 F 6.062(.T)-.74 G
1.062(he working gr)312.43 235.2 R 1.062(oup invented and standar)-.18 F(d-)
-.18 E .279(ized functionality in these ar)72 247.2 R .279
(eas, which Bash implements.)-.18 F(The)5.278 E F1(command)2.778 E F0 .278
(builtin was invented so)2.778 F 1.376
(that shell functions could be written to r)72 259.2 R 1.376
(eplace builtins; it makes the capabilities of the builtin)-.18 F .477
(available to the function.)72 271.2 R .477(The r)5.477 F .477(eserved wor)-.18
F 2.977(d`)-.18 G(`!')278.12 271.2 Q 2.977('w)-.37 G .477
(as added to negate the r)300.187 271.2 R .477(eturn value of a com-)-.18 F
1.09(mand or pipeline; it was nearly impossible to expr)72 283.2 R 1.09(ess `)
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(leanly using the sh language.)370.99 283.2 R(Ther)72 295.2 Q 3.684(ee)-.18 G
1.183(xist multiple incompatible implementations of the)105.774 295.2 R F1
(test)3.683 E F0 1.183(builtin, which tests \214les for type)3.683 F .38
(and other attributes and performs arithmetic and string comparisons.)72 307.2
R .38(POSIX consider)5.38 F .38(ed none of)-.18 F .469(these corr)72 319.2 R
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(ehavior was speci\214ed in terms of the number of ar)210.762 319.2 R .468
(guments to the)-.18 F 2.52(command. POSIX.2)72 331.2 R .021
(dictates exactly what will happen when four or fewer ar)2.52 F .021
(guments ar)-.18 F 2.521(eg)-.18 G .021(iven to)473.589 331.2 R F1(test)72
343.2 Q F0 4.905(,a)C 2.405(nd leaves the behavior unde\214ned when mor)100.505
343.2 R 4.905(ea)-.18 G -.18(rg)325.27 343.2 S 2.404(uments ar).18 F 4.904(es)
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(POSIX.2 algorithm, which was conceived by David Korn.)72 355.2 Q F1 2.5
(3.1. Features)72 379.2 R(not in the Bourne Shell)2.5 E F0(Ther)97 394.8 Q
3.958(ea)-.18 G 1.818 -.18(re a n)131.258 394.8 T 1.458(umber of minor dif).18
F(fer)-.18 E 1.458(ences between Bash and the version of sh pr)-.18 F 1.458
(esent on)-.18 F .503(most other versions of)72 406.8 R F2(UNIX)3.003 E F0
5.503(.T)C .503(he majority of these ar)212.582 406.8 R 3.002(ed)-.18 G .502
(ue to the POSIX standar)326.876 406.8 R .502(d, but some ar)-.18 F(e)-.18 E
1.173(the r)72 418.8 R 1.173(esult of Bash adopting featur)-.18 F 1.173(es fr)
-.18 F 1.173(om other shells.)-.18 F 1.174
(For instance, Bash includes the new `)6.173 F(`!')-.37 E(')-.37 E -.18(re)72
430.8 S .414(served wor).18 F .414(d, the)-.18 F F1(command)2.913 E F0 .413
(builtin, the ability of the)2.913 F F1(read)2.913 E F0 .413(builtin to corr)
2.913 F .413(ectly r)-.18 F .413(eturn a line end-)-.18 F 1.635
(ing with a backslash, symbolic ar)72 442.8 R 1.635(guments to the)-.18 F F1
(umask)4.135 E F0 1.636(builtin, variable substring r)4.136 F 1.636(emoval, a)
-.18 F .791(way to get the length of a variable, and the new algorithm for the)
72 454.8 R F1(test)3.29 E F0 .79(builtin fr)3.29 F .79(om the POSIX.2)-.18 F
(standar)72 466.8 Q(d, none of which appear in sh.)-.18 E 1.408
(Bash also implements the `)97 482.4 R(`$\(...\)')-.37 E 3.908('c)-.37 G 1.408
(ommand substitution syntax, which supersedes the sh)255.56 482.4 R .54
(`...` constr)72 494.4 R 3.04(uct. The)-.08 F -.37(``)3.04 G($\(...\)').37 E
3.04('c)-.37 G(onstr)193.76 494.4 Q .54
(uct expands to the output of the command contained within the)-.08 F(par)72
506.4 Q .708(entheses, with trailing newlines r)-.18 F 3.208(emoved. The)-.18 F
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(uch simpler and it is easier)383.64 518.4 R(to nest.)72 530.4 Q .697
(The Bourne shell does not pr)97 546 R .697(ovide such featur)-.18 F .698
(es as brace expansion, the ability to de\214ne a)-.18 F 2.079(variable and a \
function with the same name, local variables in shell functions, the ability t\
o)72 558 R 1.933
(enable and disable individual builtins or write a function to r)72 570 R 1.933
(eplace a builtin, or a means to)-.18 F(export a shell function to a child pr)
72 582 Q(ocess.)-.18 E 1.019
(Bash has closed a long-standing shell security hole by not using the)97 597.6
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.861(esults of expansion \(ksh and the 4.4 BSD sh)-.18 F .337
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(Useful behavior such as a means to abort execution of a script r)5.337 F .336
(ead with)-.18 F .282(the `)72 633.6 R(`.')-.37 E 2.782('c)-.37 G .283
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72 688 DL 80 688 76 688 DL 84 688 80 688 DL 88 688 84 688 DL 92 688 88 688 DL
96 688 92 688 DL 100 688 96 688 DL 104 688 100 688 DL 108 688 104 688 DL 112
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/F0 10/Palatino-Roman@0 SF 2.5(-4-)279.67 48 S/F1 10/Palatino-Bold@0 SF 2.5
(4. Bash-speci\214c)72 84 R(Features)2.5 E F0 .897
(This section details a few of the featur)97 99.6 R .897
(es which make Bash unique.)-.18 F .898(Most of them pr)5.898 F(ovide)-.18 E
(impr)72 111.6 Q 2.913(oved interactive use, but a few pr)-.18 F 2.912
(ogramming impr)-.18 F 2.912(ovements ar)-.18 F 5.412(ep)-.18 G -.18(re)410.494
111.6 S 2.912(sent as well.).18 F(Full)7.912 E(descriptions of these featur)72
123.6 Q(es can be found in the Bash documentation.)-.18 E F1 2.5(4.1. Startup)
72 147.6 R(Files)2.5 E F0 .207(Bash executes startup \214les dif)97 163.2 R
(fer)-.18 E .207(ently than other shells.)-.18 F .207
(The Bash behavior is a compr)5.207 F(omise)-.18 E 1.451(between the csh princ\
iple of startup \214les with \214xed names executed for each shell and the sh)
72 175.2 R -.37(``)72 187.2 S(minimalist').37 E 2.677('b)-.37 G(ehavior)138.207
187.2 Q 5.177(.A)-.74 G 2.678(ni)186.504 187.2 S .178
(nteractive instance of Bash started as a login shell r)197.912 187.2 R .178
(eads and executes)-.18 F/F2 10/Palatino-Italic@0 SF(~/.bash_pr)72 199.2 Q
(o\214le)-.18 E F0 .521(\(the \214le .bash_pr)4.687 F .52(o\214le in the user)
-.18 F .52('s home dir).74 F .52(ectory\), if it exists.)-.18 F .52
(An interactive non-)5.52 F 1.692(login shell r)72 211.2 R 1.692
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1.693(non-interactive shell \(one begun to execute a shell)271.99 211.2 R .56
(script, for example\) r)72 223.2 R .559
(eads no \214xed startup \214le, but uses the value of the variable)-.18 F F1
($ENV)3.059 E F0 3.059(,i)C 3.059(fs)470.522 223.2 S .559(et, as)481.151 223.2
R .06(the name of a startup \214le.)72 235.2 R .061(The ksh practice of r)5.06
F(eading)-.18 E F1($ENV)2.561 E F0 .061(for every shell, with the accompany-)
2.561 F 1.309(ing dif)72 247.2 R 1.309(\214culty of de\214ning the pr)-.18 F
1.308(oper variables and functions for interactive and non-interactive)-.18 F
.385(shells or having the \214le r)72 259.2 R .385
(ead only for interactive shells, was consider)-.18 F .385(ed too complex.)-.18
F .385(Ease of use)5.385 F .252(won out her)72 271.2 R 2.752(e. Inter)-.18 F
(estingly)-.18 E 2.752(,t)-1.11 G .251(he next r)202.258 271.2 R .251
(elease of ksh will change to r)-.18 F(eading)-.18 E F1($ENV)2.751 E F0 .251
(only for interac-)2.751 F(tive shells.)72 283.2 Q F1 2.5(4.2. New)72 307.2 R
(Builtin Commands)2.5 E F0(Ther)97 322.8 Q 3.077(ea)-.18 G .937 -.18(re a f)
130.377 322.8 T .577(ew builtins which ar).18 F 3.077(en)-.18 G .578
(ew or have been extended in Bash.)259.179 322.8 R(The)5.578 E F1(enable)3.078
E F0(builtin)3.078 E .073(allows builtin commands to be turned on and of)72
334.8 R 2.573(fa)-.18 G(rbitrarily)296.267 334.8 Q 5.073(.T)-1.11 G 2.573(ou)
347.87 334.8 S .073(se the version of)361.933 334.8 R F2(echo)2.573 E F0 .073
(found in a)4.239 F -1.76(user 's)72 346.8 R(sear)2.755 E .255
(ch path rather than the Bash builtin,)-.18 F/F3 10/Courier@0 SF .255
(enable -n echo)2.755 F F0(suf)2.756 E 2.756(\214ces. The)-.18 F F1(help)2.756
E F0 .256(builtin pr)2.756 F(o-)-.18 E .618
(vides quick synopses of the shell facilities without r)72 358.8 R .618
(equiring access to a manual page.)-.18 F F1(Builtin)5.618 E F0(is)3.118 E .955
(similar to)72 370.8 R F1(command)3.455 E F0 .955
(in that it bypasses shell functions and dir)3.455 F .956
(ectly executes builtin commands.)-.18 F 2.025
(Access to a csh-style stack of dir)72 382.8 R 2.025(ectories is pr)-.18 F
2.025(ovided via the)-.18 F F1(pushd)4.524 E F0(,)A F1(popd)4.524 E F0 4.524
(,a)C(nd)429.142 382.8 Q F1(dirs)4.524 E F0(builtins.)4.524 E F1(Pushd)72 394.8
Q F0(and)4.255 E F1(popd)4.255 E F0 1.755(insert and r)4.255 F 1.756(emove dir)
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4.256(,a)-1.11 G(nd)430.102 394.8 Q F1(dirs)4.256 E F0 1.756(lists the)4.256 F
.458(stack contents.)72 406.8 R .457
(On systems that allow \214ne-grained contr)5.458 F .457(ol of r)-.18 F(esour)
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1.216(used to tune these settings.)72 418.8 R F1(Ulimit)6.216 E F0 1.216
(allows a user to contr)3.716 F 1.216(ol, among other things, whether cor)-.18
F(e)-.18 E .306(dumps ar)72 430.8 R 2.806(et)-.18 G 2.806(ob)125.652 430.8 S
2.806(eg)139.448 430.8 S .306
(enerated, how much memory the shell or a child pr)152.604 430.8 R .306
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(ge a \214le cr)-.18 F .991(eated by a child pr)-.18 F .991(ocess can gr)-.18 F
(ow)-.18 E 5.991(.T)-.92 G(he)343.212 442.8 Q F1(suspend)3.491 E F0 .992
(command will stop the)3.491 F .532(shell pr)72 454.8 R .532
(ocess when job contr)-.18 F .532
(ol is active; most other shells do not allow themselves to be stopped)-.18 F
.339(like that.)72 466.8 R F1 -.9(Ty)5.339 G(pe,).9 E F0 .339
(the Bash answer to)2.839 F F1(which)2.839 E F0(and)2.839 E F1(whence,)2.839 E
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Q(typed as a command:)72 478.8 Q F3 6($t)97 496.8 S(ype export)115 496.8 Q
(export is a shell builtin)97 508.8 Q 6($t)97 520.8 S(ype -t export)115 520.8 Q
(builtin)97 532.8 Q 6($t)97 544.8 S(ype bash)115 544.8 Q(bash is /bin/bash)97
556.8 Q 6($t)97 568.8 S(ype cd)115 568.8 Q(cd is a function)97 580.8 Q(cd \(\))
97 592.8 Q({)97 604.8 Q(builtin cd ${1+"$@"} && xtitle $HOST: $PWD)121 616.8 Q
(})97 628.8 Q F0 -.92(Va)72 650.4 S 1.138(rious modes tell what a command wor)
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(which version of a command will be executed based on a user)72 662.4 R .597
('s sear).74 F .597(ch path.)-.18 F .597(Some of this func-)5.597 F
(tionality has been adopted by POSIX.2 and folded into the)72 674.4 Q F1
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(4.3. Editing)72 84 R(and Completion)2.5 E F0 1.094(One ar)97 99.6 R 1.094
(ea in which Bash shines is command line editing.)-.18 F 1.093(Bash uses the)
6.093 F/F2 10/Palatino-Italic@0 SF -.18(re)3.593 G(adline).18 E F0 1.093
(library to)5.259 F -.18(re)72 111.6 S .27(ad and edit lines when interactive.)
.18 F .271(Readline is a powerful and \215exible input facility that a user)
5.27 F .013(can con\214gur)72 123.6 R 2.513(et)-.18 G 2.513(oi)137.466 123.6 S
.013(ndividual tastes.)148.349 123.6 R .012
(It allows lines to be edited using either emacs or vi commands,)5.013 F(wher)
72 135.6 Q 3.039(et)-.18 G .539(hose commands ar)105.809 135.6 R 3.039(ea)-.18
G(ppr)202.526 135.6 Q 3.039(opriate. The)-.18 F .539
(full capability of emacs is not pr)3.039 F .54(esent \255 ther)-.18 F 3.04(ei)
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mand with M-x, for instance \255 but the existing commands ar)72 147.6 R 2.921
(em)-.18 G(or)489.98 147.6 Q(e)-.18 E 2.773(than adequate.)72 159.6 R 2.773
(The vi mode is compliant with the command line editing standar)7.773 F 2.774
(dized by)-.18 F(POSIX.2.)72 171.6 Q 1.222(Readline is fully customizable.)97
187.2 R 1.221(In addition to the basic commands and key bindings, the)6.222 F
.263(library allows users to de\214ne additional key bindings using a startup \
\214le.)72 199.2 R(The)5.263 E F2(inputr)2.763 E(c)-.18 E F0 .263
(\214le, which)4.429 F .519(defaults to the \214le)72 211.2 R F2(~/.inputr)
3.019 E(c)-.18 E F0 3.019(,i)1.666 G 3.019(sr)204.981 211.2 S .519
(ead each time r)216.01 211.2 R .519
(eadline initializes, permitting users to maintain a)-.18 F 1.084
(consistent interface acr)72 223.2 R 1.084(oss a set of pr)-.18 F 3.585
(ograms. Readline)-.18 F 1.085(includes an extensible interface, so each)3.585
F(pr)72 235.2 Q .885
(ogram using the library can add its own bindable commands and pr)-.18 F .885
(ogram-speci\214c key bind-)-.18 F 2.844(ings. Bash)72 247.2 R .345(uses this \
facility to add bindings that perform history expansion or shell wor)2.844 F
2.845(de)-.18 G(xpan-)478.68 247.2 Q(sions on the curr)72 259.2 Q
(ent input line.)-.18 E .164(Readline interpr)97 274.8 R .163
(ets a number of variables which further tune its behavior)-.18 F 5.163(.V)-.74
G .163(ariables exist to)435.264 274.8 R(contr)72 286.8 Q 2.503
(ol whether or not eight-bit characters ar)-.18 F 5.003(ed)-.18 G(ir)300.789
286.8 Q 2.503(ectly r)-.18 F 2.503(ead as input or converted to meta-)-.18 F
(pr)72 298.8 Q .076(e\214xed key sequences \(a meta-pr)-.18 F .076
(e\214xed key sequence consists of the character with the eighth bit)-.18 F
(zer)72 310.8 Q .204(oed, pr)-.18 F .204(eceded by the)-.18 F F2(meta-pr)2.704
E(e\214x)-.18 E F0(character)4.37 E 2.704(,u)-.74 G .205
(sually escape, which selects an alternate keymap\),)282.17 310.8 R .76
(to decide whether to output characters with the eighth bit set dir)72 322.8 R
.759(ectly or as a meta-pr)-.18 F .759(e\214xed key)-.18 F .19
(sequence, whether or not to wrap to a new scr)72 334.8 R .191
(een line when a line being edited is longer than the)-.18 F(scr)72 346.8 Q
.099(een width, the keymap to which subsequent key bindings should apply)-.18 F
2.598(,o)-1.11 G 2.598(re)411.096 346.8 S .098(ven what happens)422.434 346.8 R
1.031(when r)72 358.8 R 1.031(eadline wants to ring the terminal's bell.)-.18 F
1.031(All of these variables can be set in the inputr)6.031 F(c)-.18 E(\214le.)
72 370.8 Q .239(The startup \214le understands a set of C pr)97 386.4 R(epr)
-.18 E(ocessor)-.18 E .238(-like conditional constr)-.18 F .238
(ucts which allow)-.08 F 1.431
(variables or key bindings to be assigned based on the application using r)72
398.4 R 1.432(eadline, the terminal)-.18 F(curr)72 410.4 Q 1.676
(ently being used, or the editing mode.)-.18 F 1.676(Users can add pr)6.676 F
1.676(ogram-speci\214c bindings to make)-.18 F .478(their lives easier:)72
422.4 R 2.978(Ih)5.478 G .478(ave bindings that let me edit the value of)
165.012 422.4 R F1($P)2.978 E -.92(AT)-.74 G(H).92 E F0 .479
(and double-quote the cur)2.979 F(-)-.18 E -.18(re)72 434.4 S(nt or pr).18 E
(evious wor)-.18 E(d:)-.18 E/F3 10/Courier@0 SF 6(#M)97 452.4 S
(acros that are convenient for shell interaction)115 452.4 Q($if Bash)97 464.4
Q 6(#e)97 476.4 S(dit the path)115 476.4 Q
("\\C-xp": "PATH=${PATH}\\e\\C-e\\C-a\\ef\\C-f")97 488.4 Q 6(#p)97 500.4 S
(repare to type a quoted word -- insert open and close double)115 500.4 Q 6(#q)
97 512.4 S(uotes and move to just after the open quote)115 512.4 Q
("\\C-x\\"": "\\"\\"\\C-b")97 524.4 Q 6(#Q)97 536.4 S
(uote the current or previous word)115 536.4 Q("\\C-xq": "\\eb\\"\\ef\\"")97
548.4 Q($endif)97 560.4 Q F0(Ther)72 582 Q 3.06(ei)-.18 G 3.06(sar)103.27 582 S
.56(eadline command to r)122.4 582 R(e-r)-.18 E .559
(ead the \214le, so users can edit the \214le, change some bindings,)-.18 F
(and begin to use them almost immediately)72 594 Q(.)-1.11 E .701
(Bash implements the)97 609.6 R F1(bind)3.201 E F0 .701(builtin for mor)3.201 F
3.201(ed)-.18 G .701(yamic contr)299.567 609.6 R .702(ol of r)-.18 F .702
(eadline than the startup \214le)-.18 F(permits.)72 621.6 Q F1(Bind)5.572 E F0
.572(is used in several ways.)3.072 F(In)5.572 E F2(list)3.071 E F0 .571
(mode, it can display the curr)4.737 F .571(ent key bindings, list)-.18 F .752
(all the r)72 633.6 R .752(eadline editing dir)-.18 F .752
(ectives available for binding, list which keys invoke a given dir)-.18 F
(ective,)-.18 E 1.327(or output the curr)72 645.6 R 1.327
(ent set of key bindings in a format that can be incorporated dir)-.18 F 1.327
(ectly into an)-.18 F(inputr)72 657.6 Q 3.075<638c>-.18 G 3.075(le. In)113.365
657.6 R F2(batch)3.075 E F0 .575(mode, it r)4.741 F .575
(eads a series of key bindings dir)-.18 F .575(ectly fr)-.18 F .576
(om a \214le and passes them)-.18 F .751(to r)72 669.6 R 3.251(eadline. In)-.18
F .751(its most common usage,)3.251 F F1(bind)3.251 E F0 .75
(takes a single string and passes it dir)3.251 F .75(ectly to r)-.18 F(ead-)
-.18 E .604(line, which interpr)72 681.6 R .604
(ets the line as if it had just been r)-.18 F .605(ead fr)-.18 F .605
(om the inputr)-.18 F 3.105<638c>-.18 G 3.105(le. Both)406.525 681.6 R .605
(key bindings)3.105 F
(and variable assignments may appear in the string given to)72 693.6 Q F1(bind)
2.5 E F0(.)A 1.692(The r)97 709.2 R 1.691(eadline library also pr)-.18 F 1.691
(ovides an interface for)-.18 F F2 1.691(word completion)4.191 F F0 6.691(.W)C
1.691(hen the)419.582 709.2 R F2(completion)4.191 E F0 3.377
(character \(usually T)72 721.2 R 3.377(AB\) is typed, r)-.74 F 3.378
(eadline looks at the wor)-.18 F 5.878(dc)-.18 G(urr)375.406 721.2 Q 3.378
(ently being enter)-.18 F 3.378(ed and)-.18 F EP
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/F0 10/Palatino-Roman@0 SF 2.5(-6-)279.67 48 S .089
(computes the set of \214lenames of which the curr)72 84 R .088(ent wor)-.18 F
2.588(di)-.18 G 2.588(sav)326.968 84 S .088(alid pr)347.034 84 R 2.588
(e\214x. If)-.18 F(ther)2.588 E 2.588(ei)-.18 G 2.588(so)437.136 84 S .088
(nly one pos-)449.424 84 R .81(sible completion, the r)72 96 R .81
(est of the characters ar)-.18 F 3.31(ei)-.18 G .81(nserted dir)285.2 96 R
(ectly)-.18 E 3.31(,o)-1.11 G .81(therwise the common pr)365.38 96 R .81
(e\214x of)-.18 F .715(the set of \214lenames is added to the curr)72 108 R
.715(ent wor)-.18 F 3.215(d. A)-.18 F .714(second T)3.214 F .714
(AB character enter)-.74 F .714(ed immediately)-.18 F .527
(after a non-unique completion causes r)72 120 R .527
(eadline to list the possible completions; ther)-.18 F 3.027(ei)-.18 G 3.028
(sa)453.964 120 S 3.028(no)466.232 120 S(ption)480.54 120 Q .265
(to have the list displayed immediately)72 132 R 5.265(.R)-1.11 G .265
(eadline pr)255.87 132 R .264(ovides hooks so that applications can pr)-.18 F
(ovide)-.18 E 1.287(speci\214c types of completion befor)72 144 R 3.787(et)-.18
G 1.287(he default \214lename completion is attempted.)237.284 144 R 1.287
(This is quite)6.287 F 1.378(\215exible, though it is not completely user)72
156 R(-pr)-.18 E 3.877(ogrammable. Bash,)-.18 F 1.377
(for example, can complete \214le-)3.877 F 1.456
(names, command names \(including aliases, builtins, shell r)72 168 R 1.457
(eserved wor)-.18 F 1.457(ds, shell functions, and)-.18 F .598(executables fou\
nd in the \214le system\), shell variables, usernames, and hostnames.)72 180 R
.598(It uses a set of)5.598 F .346(heuristics that, while not perfect, is gene\
rally quite good at determining what type of completion)72 192 R(to attempt.)72
204 Q/F1 10/Palatino-Bold@0 SF 2.5(4.4. History)72 228 R F0 .487
(Access to the list of commands pr)97 243.6 R .487(eviously enter)-.18 F .487
(ed \(the)-.18 F/F2 10/Palatino-Italic@0 SF .487(command history)2.987 F F0
2.987(\)i)C 2.987(sp)424.717 243.6 S -.18(ro)437.954 243.6 S .486
(vided jointly).18 F .577(by Bash and the r)72 255.6 R .577(eadline library)
-.18 F 5.577(.B)-1.11 G .578(ash pr)229.432 255.6 R .578(ovides variables \()
-.18 F F1($HISTFILE)A F0(,)A F1($HISTSIZE)3.078 E F0 3.078(,a)C(nd)456.582
255.6 Q F1($HIST)3.078 E(-)-.92 E(CONTROL)72 267.6 Q F0 3.306(\)a)C .806
(nd the)135.846 267.6 R F1(history)3.306 E F0(and)3.306 E F1(fc)3.306 E F0 .805
(builtins to manipulate the history list.)3.305 F .805(The value of)5.805 F F1
($HIST)3.305 E(-)-.92 E(FILE)72 279.6 Q F0 1.393(specifes the \214le wher)3.893
F 3.893(eB)-.18 G 1.393(ash writes the command history on exit and r)209.125
279.6 R 1.394(eads it on startup.)-.18 F F1($HISTSIZE)72 291.6 Q F0 1.295
(is used to limit the number of commands saved in the history)3.795 F(.)-1.11 E
F1($HISTCONTROL)6.294 E F0(pr)72 303.6 Q .778(ovides a cr)-.18 F .779
(ude form of contr)-.08 F .779(ol over which commands ar)-.18 F 3.279(es)-.18 G
.779(aved on the history list: a value of)349.157 303.6 R F2(ignor)72 315.6 Q
(espace)-.18 E F0 .548
(means to not save commands which begin with a space; a value of)4.714 F F2
(ignor)3.047 E(edups)-.18 E F0(means)4.713 E .296
(to not save commands identical to the last command saved.)72 327.6 R F1
($HISTCONTROL)5.296 E F0 .297(was named)2.796 F F1($his-)2.797 E(tory_control)
72 339.6 Q F0 .611
(in earlier versions of Bash; the old name is still accepted for backwar)3.112
F .611(ds compatibil-)-.18 F(ity)72 351.6 Q 5.678(.T)-1.11 G(he)96.928 351.6 Q
F1(history)3.178 E F0 .678(command can r)3.178 F .678
(ead or write \214les containing the history list and display the cur)-.18 F(-)
-.18 E -.18(re)72 363.6 S .913(nt list contents.).18 F(The)5.913 E F1(fc)3.413
E F0 .913(builtin, adopted fr)3.413 F .912
(om POSIX.2 and the Korn Shell, allows display and)-.18 F -.18(re)72 375.6 S
.12(-execution, with optional editing, of commands fr).18 F .12
(om the history list.)-.18 F .12(The r)5.12 F .12(eadline library of)-.18 F
(fers)-.18 E 2.518(as)72 387.6 S .018(et of commands to sear)83.758 387.6 R
.018(ch the history list for a portion of the curr)-.18 F .017
(ent input line or a string typed)-.18 F 1.024(by the user)72 399.6 R 6.025(.F)
-.74 G(inally)136.364 399.6 Q 3.525(,t)-1.11 G(he)169.649 399.6 Q F2(history)
3.525 E F0(library)5.191 E 3.525(,g)-1.11 G 1.025(enerally incorporated dir)
257.59 399.6 R 1.025(ectly into the r)-.18 F 1.025(eadline library)-.18 F(,)
-1.11 E .709(implements a facility for history r)72 411.6 R .709
(ecall, expansion, and r)-.18 F .709(e-execution of pr)-.18 F .709
(evious commands very)-.18 F .711(similar to csh \(`)72 423.6 R .711
(`bang history')-.37 F .711(', so called because the exclamation point intr)
-.37 F .712(oduces a history sub-)-.18 F(stitution\):)72 435.6 Q/F3 10
/Courier@0 SF 6($e)97 453.6 S(cho a b c d e)115 453.6 Q 6(abcde)97 465.6 S 6
($!)97 477.6 S 6(!fghi)115 477.6 S(echo a b c d e f g h i)97 489.6 Q 6
(abcdefghi)97 501.6 S 6($!)97 513.6 S(-2)115 513.6 Q(echo a b c d e)97 525.6 Q
6(abcde)97 537.6 S 6($e)97 549.6 S(cho !-2:1-4)115 549.6 Q(echo a b c d)97
561.6 Q 6(abcd)97 573.6 S F0 .555(The command history is only saved when the s\
hell is interactive, so it is not available for use by)72 595.2 R
(shell scripts.)72 607.2 Q F1 2.5(4.5. New)72 631.2 R(Shell V)2.5 E(ariables)
-1.11 E F0(Ther)97 646.8 Q 2.916(ea)-.18 G .776 -.18(re a n)130.216 646.8 T
.416(umber of convenience variables that Bash interpr).18 F .417
(ets to make life easier)-.18 F 5.417(.T)-.74 G(hese)484.36 646.8 Q(include)72
658.8 Q F1(FIGNORE)3.043 E F0 3.043(,w)C .542(hich is a set of \214lename suf)
169.706 658.8 R .542(\214xes identifying \214les to exclude when complet-)-.18
F .167(ing \214lenames;)72 670.8 R F1(HOSTTYPE)2.667 E F0 2.667(,w)C .167
(hich is automatically set to a string describing the type of har)205.061 670.8
R(dwar)-.18 E(e)-.18 E .333(on which Bash is curr)72 682.8 R .333
(ently executing;)-.18 F F1(command_oriented_history)2.833 E F0 2.832(,w)C .332
(hich dir)380.94 682.8 R .332(ects Bash to save all)-.18 F 1.264
(lines of a multiple-line command such as a)72 694.8 R F2(while)3.765 E F0(or)
3.765 E F2(for)3.765 E F0 1.265(loop in a single history entry)3.765 F 3.765
(,a)-1.11 G(llowing)470.09 694.8 Q .13(easy r)72 706.8 R .13(e-editing; and)
-.18 F F1(IGNOREEOF)2.63 E F0 2.63(,w)C .13
(hose value indicates the number of consecutive EOF charac-)237.84 706.8 R .901
(ters that an interactive shell will r)72 718.8 R .901(ead befor)-.18 F 3.401
(ee)-.18 G .901(xiting \255 an easy way to keep yourself fr)280.258 718.8 R
.902(om being)-.18 F 3.629(logged out accidentally)72 730.8 R 8.629(.T)-1.11 G
(he)198.697 730.8 Q F1(auto_resume)6.129 E F0 3.628
(variable alters the way the shell tr)6.128 F 3.628(eats simple)-.18 F EP
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/F0 10/Palatino-Roman@0 SF 2.5(-7-)279.67 48 S .888
(command names: if job contr)72 84 R .889
(ol is active, and this variable is set, single-wor)-.18 F 3.389(ds)-.18 G .889
(imple commands)426.431 84 R .843(without r)72 96 R(edir)-.18 E .843
(ections cause the shell to \214rst look for and r)-.18 F .842
(estart a suspended job with that name)-.18 F(befor)72 108 Q 2.5(es)-.18 G
(tarting a new pr)106.41 108 Q(ocess.)-.18 E/F1 10/Palatino-Bold@0 SF 2.5
(4.6. Brace)72 132 R(Expansion)2.5 E F0 .608(Since sh of)97 147.6 R .609
(fers no convenient way to generate arbitrary strings that shar)-.18 F 3.109
(eac)-.18 G .609(ommon pr)440.711 147.6 R(e\214x)-.18 E .036(or suf)72 159.6 R
.036(\214x \(\214lename expansion r)-.18 F(equir)-.18 E .035
(es that the \214lenames exist\), Bash implements)-.18 F/F2 10
/Palatino-Italic@0 SF .035(brace expansion)2.535 F F0 2.535(,a)C .716
(capability picked up fr)72 171.6 R .716(om csh.)-.18 F .717
(Brace expansion is similar to \214lename expansion, but the strings)5.716 F
2.557(generated need not corr)72 183.6 R 2.557(espond to existing \214les.)-.18
F 5.057(Ab)7.557 G 2.557(race expr)322.296 183.6 R 2.557
(ession consists of an optional)-.18 F F2(pr)72 195.6 Q(eamble)-.18 E F0 4.412
(,f)1.666 G 1.912(ollowed by a pair of braces enclosing a series of comma-sepa\
rated strings, and an)120.028 195.6 R(optional)72 207.6 Q F2(postamble)2.842 E
F0 5.342(.T)1.666 G .342(he pr)167.49 207.6 R .342(eamble is pr)-.18 F .342
(epended to each string within the braces, and the postam-)-.18 F
(ble is then appended to each r)72 219.6 Q(esulting string:)-.18 E/F3 10
/Courier@0 SF 6($e)97 237.6 S(cho a{d,c,b}e)115 237.6 Q(ade ace abe)97 249.6 Q
F0 .898(As this example demonstrates, the r)72 271.2 R .899
(esults of brace expansion ar)-.18 F 3.399(en)-.18 G .899
(ot sorted, as they ar)374.176 271.2 R 3.399(eb)-.18 G 3.399<798c>477.961 271.2
S(le-)492.97 271.2 Q(name expansion.)72 283.2 Q F1 2.5(4.7. Process)72 307.2 R
(Substitution)2.5 E F0 .692(On systems that can support it, Bash pr)97 322.8 R
.692(ovides a facility known as)-.18 F F2(pr)3.192 E .692(ocess substitution)
-.18 F F0 5.692(.P)C -.18(ro)491.44 322.8 S(-).18 E .479(cess substitution is \
similar to command substitution in that its speci\214cation includes a command)
72 334.8 R .969(to execute, but the shell does not collect the command's outpu\
t and insert it into the command)72 346.8 R 2.925(line. Rather)72 358.8 R 2.925
(,B)-.74 G .425(ash opens a pipe to the command, which is r)136.65 358.8 R .426
(un in the backgr)-.08 F 2.926(ound. The)-.18 F .426(shell uses)2.926 F .659
(named pipes \(FIFOs\) or the)72 370.8 R F2(/dev/fd)3.158 E F0 .658
(method of naming open \214les to expand the pr)4.824 F .658(ocess substitu-)
-.18 F .559(tion to a \214lename which connects to the pipe when opened.)72
382.8 R .56(This \214lename becomes the r)5.56 F .56(esult of)-.18 F .302
(the expansion.)72 394.8 R(Pr)5.302 E .302
(ocess substitution can be used to compar)-.18 F 2.801(et)-.18 G .301
(he outputs of two dif)344.255 394.8 R(fer)-.18 E .301(ent versions)-.18 F
(of an application as part of a r)72 406.8 Q(egr)-.18 E(ession test:)-.18 E F3
6($c)97 424.8 S(mp <\(old_prog\) <\(new_prog\))115 424.8 Q F1 2.5(4.8. Prompt)
72 454.8 R(Customization)2.5 E F0 .745(One of the mor)97 470.4 R 3.245(ep)-.18
G .745(opular interactive featur)179.97 470.4 R .745(es that Bash pr)-.18 F
.745(ovides is the ability to customize)-.18 F 1.946(the pr)72 482.4 R 4.446
(ompt. Both)-.18 F F1($PS1)4.446 E F0(and)4.446 E F1($PS2,)4.446 E F0 1.945
(the primary and secondary pr)4.445 F 1.945(ompts, ar)-.18 F 4.445(ee)-.18 G
1.945(xpanded befor)432.885 482.4 R(e)-.18 E 2.168(being displayed.)72 494.4 R
2.168(Parameter and variable expansion is performed when the pr)7.168 F 2.169
(ompt string is)-.18 F .77
(expanded, so any shell variable can be put into the pr)72 506.4 R .77
(ompt \(e.g.,)-.18 F F1($SHL)3.27 E(VL)-.92 E F0 3.27(,w)C .77
(hich indicates how)419.37 506.4 R .609(deeply the curr)72 518.4 R .609
(ent shell is nested\).)-.18 F .609(Bash specially interpr)5.609 F .609
(ets characters in the pr)-.18 F .61(ompt string pr)-.18 F(e-)-.18 E 1.224
(ceded by a backslash.)72 530.4 R 1.224(Some of these backslash escapes ar)
6.224 F 3.724(er)-.18 G 1.224(eplaced with the curr)348.91 530.4 R 1.224
(ent time, the)-.18 F .542(date, the curr)72 542.4 R .542(ent working dir)-.18
F(ectory)-.18 E 3.042(,t)-1.11 G .542
(he username, and the command number or history number)237.3 542.4 R .623
(of the command being enter)72 554.4 R 3.123(ed. Ther)-.18 F 3.123(ei)-.18 G
3.122(se)249.038 554.4 S .622
(ven a backslash escape to cause the shell to change its)261.19 554.4 R(pr)72
566.4 Q 1.098(ompt when r)-.18 F 1.098(unning as r)-.08 F 1.098(oot after an)
-.18 F F2(su)3.599 E F0 6.099(.B)C(efor)273.626 566.4 Q 3.599(ep)-.18 G 1.099
(rinting each primary pr)305.375 566.4 R 1.099(ompt, Bash expands)-.18 F 1.458
(the variable)72 578.4 R F1($PROMPT_COMMAND)3.958 E F0 1.457
(and, if it has a value, executes the expanded value as a)3.957 F 1.038
(command, allowing additional pr)72 590.4 R 1.038(ompt customization.)-.18 F
1.038(For example, this assignment causes the)6.038 F(curr)72 602.4 Q .754
(ent user)-.18 F 3.254(,t)-.74 G .754(he curr)134.598 602.4 R .753
(ent host, the time, the last component of the curr)-.18 F .753
(ent working dir)-.18 F(ectory)-.18 E 3.253(,t)-1.11 G(he)493.39 602.4 Q .813
(level of shell nesting, and the history number of the curr)72 614.4 R .813
(ent command to be embedded into the)-.18 F(primary pr)72 626.4 Q(ompt:)-.18 E
F3 6($P)97 644.4 S(S1='\\u@\\h [\\t] \\W\($SHLVL:\\!\)\\$ ')115 644.4 Q
(chet@odin [21:03:44] documentation\(2:636\)$ cd ..)97 656.4 Q
(chet@odin [21:03:54] src\(2:637\)$)97 668.4 Q F0 1.289
(The string being assigned is surr)72 690 R 1.289
(ounded by single quotes so that if it is exported, the value of)-.18 F F1
($SHL)72 702 Q(VL)-.92 E F0(will be updated by a child shell:)2.5 E F3
(chet@odin [21:17:35] src\(2:638\)$ export PS1)97 720 Q EP
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/F0 10/Palatino-Roman@0 SF 2.5(-8-)279.67 48 S/F1 10/Courier@0 SF
(chet@odin [21:17:40] src\(2:639\)$ bash)97 84 Q
(chet@odin [21:17:46] src\(3:696\)$)97 96 Q F0 .981
(The \\$ escape is displayed as `)72 117.6 R(`)-.37 E/F2 10/Palatino-Bold@0 SF
($)A F0 1.721 -.37('' w)D .981(hen r).37 F .981(unning as a normal user)-.08 F
3.481(,b)-.74 G .981(ut as `)382.843 117.6 R(`)-.37 E F2(#)A F0 1.721 -.37
('' w)D .982(hen r).37 F .982(unning as)-.08 F -.18(ro)72 129.6 S(ot.).18 E F2
2.5(4.9. File)72 153.6 R(System V)2.5 E(iews)-.55 E F0 .42(Since Berkeley intr)
97 169.2 R .42(oduced symbolic links in 4.2 BSD, one of their most annoying pr)
-.18 F(operties)-.18 E .705(has been the `)72 181.2 R(`warping')-.37 E 3.205
('t)-.37 G 3.205(oac)185.91 181.2 S .705(ompletely dif)207.22 181.2 R(fer)-.18
E .705(ent ar)-.18 F .705(ea of the \214le system when using)-.18 F F2(cd)3.206
E F0 3.206(,a)C .706(nd the)474.994 181.2 R -.18(re)72 193.2 S 2.292
(sultant non-intuitive behavior of `).18 F(`)-.37 E F2 2.292(cd ..)B F0 -.37
('')C 7.291(.T).37 G(he)282.761 193.2 Q/F3 9/Palatino-Roman@0 SF(UNIX)4.791 E
F0 2.291(kernel tr)4.791 F 2.291(eats symbolic links)-.18 F/F4 10
/Palatino-Italic@0 SF(physically)4.791 E F0(.)1.666 E .225(When the kernel is \
translating a pathname in which one component is a symbolic link, it r)72 205.2
R(eplaces)-.18 E .81(all or part of the pathname while pr)72 217.2 R .81
(ocessing the link.)-.18 F .81(If the contents of the symbolic link begin)5.81
F .033(with a slash, the kernel r)72 229.2 R .033(eplaces the pathname entir)
-.18 F .033(ely; if not, the link contents r)-.18 F .034(eplace the curr)-.18 F
(ent)-.18 E 2.814(component. In)72 241.2 R .314
(either case, the symbolic link is visible.)2.814 F .313
(If the link value is an absolute pathname,)5.314 F
(the user \214nds himself in a completely dif)72 253.2 Q(fer)-.18 E
(ent part of the \214le system.)-.18 E 1.291(Bash pr)97 268.8 R 1.291(ovides a)
-.18 F F4(logical)3.791 E F0 1.291(view of the \214le system.)5.457 F 1.292
(In this default mode, command and \214le-)6.292 F .727
(name completion and builtin commands such as)72 280.8 R F2(cd)3.227 E F0(and)
3.227 E F2(pushd)3.227 E F0 .727(which change the curr)3.227 F .727(ent work-)
-.18 F .245(ing dir)72 292.8 R .245(ectory transpar)-.18 F .245
(ently follow symbolic links as if they wer)-.18 F 2.746(ed)-.18 G(ir)365.822
292.8 Q 2.746(ectories. The)-.18 F F2($PWD)2.746 E F0(variable,)2.746 E .562
(which holds the shell's idea of the curr)72 304.8 R .561(ent working dir)-.18
F(ectory)-.18 E 3.061(,d)-1.11 G .561(epends on the path used to r)354.924
304.8 R(each)-.18 E(the dir)72 316.8 Q
(ectory rather than its physical location in the local \214le system hierar)
-.18 E(chy)-.18 E 5(.F)-1.11 G(or example:)427.35 316.8 Q F1 6($c)97 334.8 S 6
(d/)115 334.8 S(usr/local/bin)133 334.8 Q 6($e)97 346.8 S(cho $PWD)115 346.8 Q
(/usr/local/bin)97 358.8 Q 6($p)97 370.8 S(wd)115 370.8 Q(/usr/local/bin)97
382.8 Q 6($/)97 394.8 S(bin/pwd)115 394.8 Q(/net/share/sun4/local/bin)97 406.8
Q 6($c)97 418.8 S 6(d.)115 418.8 S(.)133 418.8 Q 6($p)97 430.8 S(wd)115 430.8 Q
(/usr/local)97 442.8 Q 6($/)97 454.8 S(bin/pwd)115 454.8 Q
(/net/share/sun4/local)97 466.8 Q 6($c)97 478.8 S 6(d.)115 478.8 S(.)133 478.8
Q 6($p)97 490.8 S(wd)115 490.8 Q(/usr)97 502.8 Q 6($/)97 514.8 S(bin/pwd)115
514.8 Q(/usr)97 526.8 Q F0 .094(One pr)72 548.4 R .094
(oblem with this, of course, arises when pr)-.18 F .095
(ograms that do not understand the shell's logical)-.18 F .805
(notion of the \214le system interpr)72 560.4 R .805(et `)-.18 F(`..')-.37 E
3.305('d)-.37 G(if)251.245 560.4 Q(fer)-.18 E(ently)-.18 E 5.805(.T)-1.11 G
.804(his generally happens when Bash completes)304.86 560.4 R 1.864
(\214lenames containing `)72 572.4 R(`..')-.37 E 4.364('a)-.37 G(ccor)194.902
572.4 Q 1.864(ding to a logical hierar)-.18 F 1.865(chy which does not corr)
-.18 F 1.865(espond to their)-.18 F .584(physical location.)72 584.4 R .583
(For users who \214nd this tr)5.584 F .583(oublesome, a corr)-.18 F(esponding)
-.18 E F4(physical)3.083 E F0 .583(view of the \214le)4.749 F
(system is available:)72 596.4 Q F1 6($c)97 614.4 S 6(d/)115 614.4 S
(usr/local/bin)133 614.4 Q 6($p)97 626.4 S(wd)115 626.4 Q(/usr/local/bin)97
638.4 Q 6($s)97 650.4 S(et -o physical)115 650.4 Q 6($p)97 662.4 S(wd)115 662.4
Q(/net/share/sun4/local/bin)97 674.4 Q EP
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/F0 10/Palatino-Roman@0 SF 2.5(-9-)279.67 48 S/F1 10/Palatino-Bold@0 SF 2.5
(4.10. Internationalization)72 84 R F0 .316(One of the most signi\214cant impr)
97 99.6 R .316(ovements in version 1.13 of Bash was the change to `)-.18 F
(`eight-)-.37 E .534(bit cleanliness')72 111.6 R 3.034('. Pr)-.37 F .533
(evious versions used the eighth bit of characters to mark whether or not they)
-.18 F(wer)72 123.6 Q 3.109(eq)-.18 G .609(uoted when performing wor)102.399
123.6 R 3.109(de)-.18 G 3.109(xpansions. While)244.335 123.6 R .609
(this did not af)3.109 F .61(fect the majority of users,)-.18 F 1.249
(most of whom used only seven-bit ASCII characters, some found it con\214ning.)
72 135.6 R 1.248(Beginning with)6.248 F .251
(version 1.13, Bash implemented a dif)72 147.6 R(fer)-.18 E .251
(ent quoting mechanism that did not alter the eighth bit of)-.18 F 3.228
(characters. This)72 159.6 R .727(allowed Bash to manipulate \214les with `)
3.228 F(`odd')-.37 E 3.227('c)-.37 G .727(haracters in their names, but did)
356.825 159.6 R 1.924
(nothing to help users enter those names, so version 1.13 intr)72 171.6 R 1.925
(oduced changes to r)-.18 F 1.925(eadline that)-.18 F .658
(made it eight-bit clean as well.)72 183.6 R .658(Options exist that for)5.658
F .658(ce r)-.18 F .658(eadline to attach no special signi\214cance)-.18 F .834
(to characters with the eighth bit set \(the default behavior is to convert th\
ese characters to meta-)72 195.6 R(pr)72 207.6 Q 2.375(e\214xed key sequences\
\) and to output these characters without conversion to meta-pr)-.18 F
(e\214xed)-.18 E 2.924(sequences. These)72 219.6 R .424
(changes, along with the expansion of keymaps to a full eight bits, enable r)
2.924 F(ead-)-.18 E 1.025(line to work with most of the ISO-8859 family of cha\
racter sets, used by many Eur)72 231.6 R 1.025(opean coun-)-.18 F(tries.)72
243.6 Q F1(4.1)72 267.6 Q 2.5(1. POSIX)-.37 F(Mode)2.5 E F0 .834
(Although Bash is intended to be POSIX.2 conformant, ther)97 283.2 R 3.334(ea)
-.18 G 1.194 -.18(re a)374.606 283.2 T -.18(re).18 G .835
(as in which the default).18 F .622
(behavior is not compatible with the standar)72 295.2 R 3.121(d. For)-.18 F
.621(users who wish to operate in a strict POSIX.2)3.121 F(envir)72 307.2 Q
2.453(onment, Bash implements a)-.18 F/F2 10/Palatino-Italic@0 SF 2.453
(POSIX mode)4.953 F F0 7.453(.W)C 2.453
(hen this mode is active, Bash modi\214es its)305.808 307.2 R .969
(default operation wher)72 319.2 R 3.469(ei)-.18 G 3.469(td)186.917 319.2 S(if)
199.756 319.2 Q .969(fers fr)-.18 F .969(om POSIX.2 to match the standar)-.18 F
3.468(d. POSIX)-.18 F .968(mode is enter)3.468 F(ed)-.18 E .474
(when Bash is started with the)72 331.2 R F1(-posix)2.974 E F0 2.974
(option. This)2.974 F(featur)2.974 E 2.974(ei)-.18 G 2.975(sa)334.31 331.2 S
.475(lso available as an option to the)346.525 331.2 R F1(set)2.975 E F0
(builtin,)72 343.2 Q F1 1.631(set -o posix)4.131 F F0 6.631(.F)C 1.631
(or compatibility with other GNU softwar)177.054 343.2 R 4.131(et)-.18 G 1.63
(hat attempts to be POSIX.2)379.02 343.2 R .627
(compliant, Bash also enters POSIX mode if the variable)72 355.2 R F1($POSIXL)
3.128 E(Y_CORRECT)-.92 E F0 .628(is set when Bash)3.128 F .891
(is started or assigned a value during execution.)72 367.2 R F1
($POSIX_PEDANTIC)5.891 E F0 .89(is accepted as well, to be)3.391 F .445
(compatible with some older GNU utilities.)72 379.2 R .446
(When Bash is started in POSIX mode, for example, it)5.445 F(sour)72 391.2 Q
.342(ces the \214le named by the value of)-.18 F F1($ENV)2.842 E F0 .342
(rather than the `)2.842 F(`normal')-.37 E 2.842('s)-.37 G .341
(tartup \214les, and does not)392.566 391.2 R(allow r)72 403.2 Q(eserved wor)
-.18 E(ds to be aliased.)-.18 E F1 2.5(5. New)72 427.2 R
(Features and Future Plans)2.5 E F0(Ther)97 442.8 Q 4.157(ea)-.18 G 2.017 -.18
(re s)131.457 442.8 T 1.658(everal featur).18 F 1.658(es intr)-.18 F 1.658
(oduced in the curr)-.18 F 1.658(ent version of Bash, version 1.14, and a)-.18
F .714(number under consideration for futur)72 454.8 R 3.214(er)-.18 G 3.214
(eleases. This)253.61 454.8 R .714
(section will brie\215y detail the new featur)3.214 F(es)-.18 E
(in version 1.14 and describe several featur)72 466.8 Q
(es that may appear in later versions.)-.18 E F1 2.5(5.1. New)72 490.8 R
(Features in Bash-1.14)2.5 E F0 1.303(The new featur)97 506.4 R 1.304
(es available in Bash-1.14 answer several of the most common r)-.18 F 1.304
(equests for)-.18 F 2.815(enhancements. Most)72 518.4 R(notably)2.815 E 2.815
(,t)-1.11 G(her)209.475 518.4 Q 2.815(ei)-.18 G 2.815(sam)234.37 518.4 S .314
(echanism for including non-visible character sequences)258.07 518.4 R 1.795
(in pr)72 530.4 R 1.796
(ompts, such as those which cause a terminal to print characters in dif)-.18 F
(fer)-.18 E 1.796(ent colors or in)-.18 F .354(standout mode.)72 542.4 R(Ther)
5.354 E 2.854(ew)-.18 G .354(as nothing pr)183.572 542.4 R .353
(eventing the use of these sequences in earlier versions, but)-.18 F 2.113
(the r)72 554.4 R 2.113(eadline r)-.18 F 2.114
(edisplay algorithm assumed each character occupied physical scr)-.18 F 2.114
(een space and)-.18 F(would wrap lines pr)72 566.4 Q(ematur)-.18 E(ely)-.18 E
(.)-1.11 E 1.183(Readline has a few new variables, several new bindable comman\
ds, and some additional)97 582 R 1.399(emacs mode default key bindings.)72 594
R 3.899(An)6.399 G 1.399(ew history sear)252.724 594 R 1.4
(ch mode has been implemented: in this)-.18 F .033(mode, r)72 606 R .033
(eadline sear)-.18 F .032(ches the history for lines beginning with the charac\
ters between the beginning)-.18 F .452(of the curr)72 618 R .452
(ent line and the cursor)-.18 F 5.452(.T)-.74 G .452(he existing r)233.074 618
R .452(eadline incr)-.18 F .452(emental sear)-.18 F .453(ch commands no longer)
-.18 F .947(match identical lines mor)72 630 R 3.447(et)-.18 G .947(han once.)
198.068 630 R .946(Filename completion now expands variables in dir)5.947 F
(ectory)-.18 E 2.516(names. The)72 642 R .016(history expansion facilities ar)
2.516 F 2.516(en)-.18 G .017
(ow nearly completely csh-compatible: missing modi-)270.006 642 R
(\214ers have been added and history substitution has been extended.)72 654 Q
.535(Several of the featur)97 669.6 R .535(es described earlier)-.18 F 3.035
(,s)-.74 G .535(uch as)282.59 669.6 R F1 .534(set -o posix)3.035 F F0(and)3.034
E F1($POSIX_PEDANTIC)3.034 E F0 3.034(,a)C -.18(re)495.44 669.6 S .749
(new in version 1.14.)72 681.6 R(Ther)5.749 E 3.249(ei)-.18 G 3.249(san)199.455
681.6 S .749(ew shell variable,)221.013 681.6 R F1(OSTYPE)3.249 E F0 3.25(,t)C
3.25(ow)351.81 681.6 S .75(hich Bash assigns a value that)368.86 681.6 R .417
(identi\214es the version of)72 693.6 R/F3 9/Palatino-Roman@0 SF(UNIX)2.917 E
F0 .416(it's r)2.917 F .416(unning on \(gr)-.08 F .416(eat for putting ar)-.18
F(chitectur)-.18 E .416(e-speci\214c binary dir)-.18 F(ec-)-.18 E 2.257
(tories into the)72 705.6 R F1($P)4.757 E -.92(AT)-.74 G(H).92 E F0 4.757
(\). T)B 2.257(wo variables have been r)-.9 F(enamed:)-.18 E F1($HISTCONTROL)
4.758 E F0 -.18(re)4.758 G(places).18 E F1($his-)4.758 E(tory_control)72 717.6
Q F0 5.733(,a)C(nd)140.793 717.6 Q F1($HOSTFILE)5.733 E F0 -.18(re)5.732 G
(places).18 E F1($hostname_completion_\214le)5.732 E F0 8.232(.I)C 5.732(nb)
401.622 717.6 S 3.232(oth cases, the old)418.704 717.6 R 2.337(names ar)72
729.6 R 4.837(ea)-.18 G 2.338(ccepted for backwar)128.914 729.6 R 2.338
(ds compatibility)-.18 F 7.338(.T)-1.11 G 2.338(he ksh)311.846 729.6 R F2
(select)4.838 E F0(constr)6.504 E 2.338(uct, which allows the)-.08 F EP
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/F0 10/Palatino-Roman@0 SF 2.5(-1)277.17 48 S 2.5(0-)288 48 S .565
(generation of simple menus, has been implemented.)72 84 R .564
(New capabilities have been added to exist-)5.565 F 1.446(ing variables:)72 96
R/F1 10/Palatino-Bold@0 SF($auto_resume)3.946 E F0 1.446
(can now take values of)3.946 F/F2 10/Palatino-Italic@0 SF(exact)3.947 E F0(or)
5.613 E F2(substring)3.947 E F0 3.947(,a)1.666 G(nd)405.913 96 Q F1
($HISTCONTROL)3.947 E F0 1.8(understands the value)72 108 R F2(ignor)4.3 E
(eboth)-.18 E F0 4.3(,w)1.666 G 1.799(hich combines the two pr)238.106 108 R
1.799(eviously acceptable values.)-.18 F(The)6.799 E F1(dirs)72 120 Q F0 2.612
(builtin has acquir)5.112 F 2.613
(ed options to print out speci\214c members of the dir)-.18 F 2.613
(ectory stack.)-.18 F(The)7.613 E F1($nolinks)72 132 Q F0 .177
(variable, which for)2.677 F .176
(ces a physical view of the \214le system, has been superseded by the)-.18 F F1
<ad50>2.676 E F0 1.486(option to the)72 144 R F1(set)3.986 E F0 1.486
(builtin \(equivalent to)3.986 F F1 1.486(set -o physical)3.986 F F0 1.486
(\); the variable is r)B 1.486(etained for backwar)-.18 F(ds)-.18 E
(compatibility)72 156 Q 5.564(.T)-1.11 G .564(he version string contained in)
144.074 156 R F1($BASH_VERSION)3.064 E F0 .563(now includes an indication of)
3.064 F .501(the patch level as well as the `)72 168 R .501(`build version')
-.37 F 3.001('. Some)-.37 F .502(little-used featur)3.001 F .502
(es have been r)-.18 F 3.002(emoved: the)-.18 F F1(bye)72 180 Q F0 .943
(synonym for)3.443 F F1(exit)3.443 E F0 .943(and the)3.443 F F1($NO_PROMPT_V)
3.443 E(ARS)-1.29 E F0 .943(variable ar)3.443 F 3.443(eg)-.18 G 3.443
(one. Ther)379.707 180 R 3.443(ei)-.18 G 3.443(sn)435.873 180 S .942(ow an or)
449.376 180 R(ga-)-.18 E(nized test suite that can be r)72 192 Q(un as a r)-.08
E(egr)-.18 E(ession test when building a new version of Bash.)-.18 E 1.42
(The documentation has been thor)97 207.6 R 1.421(oughly over)-.18 F 1.421
(hauled: ther)-.18 F 3.921(ei)-.18 G 3.921(san)372.184 207.6 S 1.421
(ew manual page on the)395.086 207.6 R -.18(re)72 219.6 S 1.142
(adline library and the).18 F F2(info)3.642 E F0 1.142
(\214le has been updated to r)3.642 F 1.142(e\215ect the curr)-.18 F 1.142
(ent version.)-.18 F 1.141(As always, as)6.142 F
(many bugs as possible have been \214xed, although some sur)72 231.6 Q(ely r)
-.18 E(emain.)-.18 E F1 2.5(5.2. Other)72 255.6 R(Features)2.5 E F0(Ther)97
271.2 Q 3.692(ea)-.18 G 1.552 -.18(re a f)130.992 271.2 T 1.192(ew featur).18 F
1.192(es that I hope to include in later Bash r)-.18 F 3.693(eleases. Some)-.18
F(ar)3.693 E 3.693(eb)-.18 G 1.193(ased on)468.887 271.2 R(work alr)72 283.2 Q
(eady done in other shells.)-.18 E 2.717
(In addition to simple variables, a futur)97 298.8 R 5.217(er)-.18 G 2.716
(elease of Bash will include one-dimensional)297.159 298.8 R .575
(arrays, using the ksh implementation of arrays as a model.)72 310.8 R .575
(Additions to the ksh syntax, such as)5.575 F F2(varname)72 322.8 Q F0 1.116
(=\( ... \) to assign a list of wor)B 1.115(ds dir)-.18 F 1.115
(ectly to an array and a mechanism to allow the)-.18 F F1(read)3.615 E F0 .492
(builtin to r)72 334.8 R .492(ead a list of values dir)-.18 F .493
(ectly into an array)-.18 F 2.993(,w)-1.11 G .493(ould be desirable.)313.615
334.8 R .493(Given those extensions,)5.493 F .621(the ksh)72 346.8 R F1 .621
(set \255A)3.121 F F0 .621(syntax may not be worth supporting \(the)3.121 F F1
<ad41>3.12 E F0 .62(option assigns a list of values to an)3.12 F(array)72 358.8
Q 2.5(,b)-1.11 G(ut is a rather peculiar special case\).)104.88 358.8 Q .522
(Some shells include a means of)97 374.4 R F2(pr)3.022 E(ogrammable)-.18 E F0
(wor)3.022 E 3.022(dc)-.18 G .522(ompletion, wher)331.796 374.4 R 3.023(et)-.18
G .523(he user speci\214es on)416.561 374.4 R 3.291(ap)72 386.4 S(er)86.301
386.4 Q .791(-command basis how the ar)-.18 F .791(guments of the command ar)
-.18 F 3.291(et)-.18 G 3.29(ob)358.98 386.4 S 3.29(et)373.26 386.4 S -.18(re)
384.6 386.4 S .79(ated when completion is).18 F .588
(attempted: as \214lenames, hostnames, executable \214les, and so on.)72 398.4
R .589(The other aspects of the curr)5.589 F(ent)-.18 E .649
(Bash implementation could r)72 410.4 R .648
(emain as-is; the existing heuristics would still be valid.)-.18 F .648
(Only when)5.648 F 2.136(completing the ar)72 422.4 R 2.137
(guments to a simple command would the pr)-.18 F 2.137
(ogrammable completion be in)-.18 F(ef)72 434.4 Q(fect.)-.18 E .223
(It would also be nice to give the user \214ner)97 450 R .223(-grained contr)
-.18 F .222(ol over which commands ar)-.18 F 2.722(es)-.18 G(aved)482.45 450 Q
1.603(onto the history list.)72 462 R 1.604(One pr)6.604 F 1.604
(oposal is for a variable, tentatively named)-.18 F F1(HISTIGNORE)4.104 E F0
4.104(,w)C(hich)485.01 462 Q .471
(would contain a colon-separated list of commands.)72 474 R .471
(Lines beginning with these commands, after)5.471 F .056(the r)72 486 R .056
(estrictions of)-.18 F F1($HISTCONTROL)2.556 E F0 .057
(have been applied, would not be placed onto the history list.)2.556 F 1.246(T\
he shell pattern-matching capabilities could also be available when specifying\
 the contents of)72 498 R F1($HISTIGNORE)72 510 Q F0(.)A .612
(One thing that newer shells such as)97 525.6 R F1(wksh)3.112 E F0 .612
(\(also known as)3.112 F F1(dtksh)3.112 E F0 3.112(\)p)C -.18(ro)397.502 525.6
S .612(vide is a command to).18 F 1.826
(dynamically load code implementing additional builtin commands into a r)72
537.6 R 1.826(unning shell.)-.08 F(This)6.826 E 1.2
(new builtin would take an object \214le or shar)72 549.6 R 1.2
(ed library implementing the `)-.18 F(`body')-.37 E 3.7('o)-.37 G 3.7(ft)450.03
549.6 S 1.2(he builtin)460.32 549.6 R(\()72 561.6 Q F2(xxx_builtin\(\))A F0
1.094(for those familiar with Bash internals\) and a str)3.595 F(uctur)-.08 E
3.594(ec)-.18 G 1.094(ontaining the name of the)386.094 561.6 R .731
(new command, the function to call when the new builtin is invoked \(pr)72
573.6 R .731(esumably de\214ned in the)-.18 F(shar)72 585.6 Q .881
(ed object speci\214ed as an ar)-.18 F .881
(gument\), and the documentation to be printed by the)-.18 F F1(help)3.38 E F0
(com-)3.38 E .974(mand \(possibly pr)72 597.6 R .974(esent in the shar)-.18 F
.975(ed object as well\).)-.18 F .975(It would manage the details of extending)
5.975 F(the internal table of builtins.)72 609.6 Q 2.641(Af)97 625.2 S .141
(ew other builtins would also be desirable: two ar)110.751 625.2 R 2.641(et)
-.18 G .14(he POSIX.2)337.93 625.2 R F1(getconf)2.64 E F0 .14(command, which)
2.64 F 1.518(prints the values of system con\214guration variables de\214ned b\
y POSIX.2, and a)72 637.2 R F1(disown)4.019 E F0(builtin,)4.019 E .93
(which causes a shell r)72 649.2 R .929(unning with job contr)-.08 F .929
(ol active to `)-.18 F(`for)-.37 E .929(get about')-.18 F 3.429('o)-.37 G .929
(ne or mor)397.563 649.2 R 3.429(eb)-.18 G(ackgr)456.25 649.2 Q(ound)-.18 E
.095(jobs in its internal jobs table.)72 661.2 R(Using)5.095 E F1(getconf)2.595
E F0 2.595(,f)C .095(or example, a user could r)274.02 661.2 R .096
(etrieve a value for)-.18 F F1($P)2.596 E -.92(AT)-.74 G(H).92 E F0 .73
(guaranteed to \214nd all of the POSIX standar)72 673.2 R 3.23(du)-.18 G .73
(tilities, or \214nd out how long \214lenames may be in)282.86 673.2 R
(the \214le system containing a speci\214ed dir)72 685.2 Q(ectory)-.18 E(.)
-1.11 E(Ther)97 700.8 Q 4.171(ea)-.18 G 2.031 -.18(re n)131.471 700.8 T 4.171
(oi).18 G 1.671(mplementation timetables for any of these featur)162.563 700.8
R 1.672(es, nor ar)-.18 F 4.172(et)-.18 G(her)443.888 700.8 Q 4.172(ec)-.18 G
(oncr)471.67 700.8 Q(ete)-.18 E .034(plans to include them.)72 712.8 R .034
(If anyone has comments on these pr)5.034 F .034(oposals, feel fr)-.18 F .033
(ee to send me electr)-.18 F(onic)-.18 E(mail.)72 724.8 Q EP
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/F0 10/Palatino-Roman@0 SF 2.5(-1)277.445 48 S 2.5(1-)287.725 48 S/F1 10
/Palatino-Bold@0 SF 2.5(6. Re\215ections)72 84 R(and Lessons Learned)2.5 E F0
1.503(The lesson that has been r)97 99.6 R 1.504
(epeated most often during Bash development is that ther)-.18 F 4.004(ea)-.18 G
-.18(re)495.44 99.6 S 1.052
(dark corners in the Bourne Shell, and people use all of them.)72 111.6 R 1.051
(In the original description of the)6.052 F 1.37
(Bourne shell, quoting and the shell grammar ar)72 123.6 R 3.87(eb)-.18 G 1.37
(oth poorly speci\214ed and incomplete; subse-)304.61 123.6 R .387
(quent descriptions have not helped much.)72 135.6 R .387(The grammar pr)5.387
F .386(esented in Bourne's paper describing)-.18 F .059
(the shell distributed with the Seventh Edition of)72 147.6 R/F2 9
/Palatino-Roman@0 SF(UNIX)2.559 E F0 2.559<8769>C 2.559(ss)321.048 147.6 S
2.559(of)332.087 147.6 S .059(ar of)343.436 147.6 R 2.559(ft)-.18 G .059
(hat it does not allow the com-)372.704 147.6 R(mand)72 159.6 Q/F3 10/Courier@0
SF(who|wc)2.5 E F0 5(.I)C 2.5(nf)147.13 159.6 S(act, as T)158.78 159.6 Q
(om Duf)-.92 E 2.5(fs)-.18 G(tates:)237.21 159.6 Q .985(Nobody r)97 175.2 R
.984(eally knows what the Bourne shell's grammar is.)-.18 F .984
(Even examination of the)5.984 F(sour)97 187.2 Q(ce code is little help.\210)
-.18 E .782(The POSIX.2 standar)72 202.8 R 3.282(di)-.18 G .782(ncludes a)
177.496 202.8 R/F4 10/Palatino-Italic@0 SF(yacc)3.282 E F0 .782
(grammar that comes close to capturing the Bourne shell's)3.282 F(behavior)72
214.8 Q 3.67(,b)-.74 G 1.17(ut it disallows some constr)122.07 214.8 R 1.169
(ucts which sh accepts without complaint \255 and ther)-.08 F 3.669(ea)-.18 G
-.18(re)495.44 214.8 S .223(scripts out ther)72 226.8 R 2.723(et)-.18 G .223
(hat use them.)149.659 226.8 R .224(It took a few versions and several bug r)
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R .427(mented sh-compatible quoting, and ther)72 238.8 R 2.927(ea)-.18 G .787
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(eviously)-.18 E 6.507(.T)-1.11 G 1.507(he r)185.841 278.4 R 1.507
(eadline library could stand a substantial r)-.18 F 4.006(ewrite. A)-.18 F
(hand-written)4.006 E .574(parser to r)72 290.4 R .574(eplace the curr)-.18 F
(ent)-.18 E F4(yacc)3.074 E F0 .574(-generated one would pr)B .574(obably r)
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302.4 R 4.365(oblem: the)-.18 F 1.864(shell could parse commands in `)4.364 F
(`$\(...\)')-.37 E 4.364('c)-.37 G(onstr)408.058 302.4 Q 1.864(ucts as they ar)
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189.785 342 T 1.009(everal cases wher).18 F 3.509(eB)-.18 G 1.009(ash tr)
300.041 342 R 1.008(eats a variable specially to enable func-)-.18 F 1.316
(tionality available another way \()72 354 R F1($notify)A F0(vs.)3.816 E F1
1.316(set -o notify)6.316 F F0(and)3.816 E F1($nolinks)3.816 E F0(vs.)3.816 E
F1 1.316(set -o physical)3.816 F F0 3.816(,f)C(or)494.59 354 Q .925
(instance\); the special tr)72 366 R .925
(eatment of the variable name should pr)-.18 F .925(obably be r)-.18 F 3.425
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3.865(,w)C 1.365(hich causes the shell to)397.55 426 R 1.047
(attempt to save all lines of a multi-line command in a single history entry)72
438 R 3.547(,s)-1.11 G 1.047(hould be made the)418.109 438 R
(default and the variable r)72 450 Q(emoved.)-.18 E F1 2.5(7. A)72 474 R
(vailability)-.7 E F0 6.17(As with all other GNU softwar)97 489.6 R 6.17
(e, Bash is available for anonymous FTP fr)-.18 F(om)-.18 E F4(pr)72 501.6 Q
(ep.ai.mit.edu:/pub/gnu)-.18 E F0 2.136(and fr)6.302 F 2.136
(om other GNU softwar)-.18 F 4.635(em)-.18 G(irr)334.21 501.6 Q 2.135
(or sites.)-.18 F 2.135(The curr)7.135 F 2.135(ent version is in)-.18 F F4
(bash-1.14.1.tar)72 513.6 Q(.gz)-.74 E F0 .241(in that dir)4.407 F(ectory)-.18
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(to \214nd the near)4.407 F .241(est ar)-.18 F .241(chive site.)-.18 F .242
(The latest version is)5.241 F .295(always available for FTP fr)72 525.6 R(om)
-.18 E F4(bash.CWRU.Edu:/pub/dist.)2.795 E F0 .295
(Bash documentation is available for FTP)4.461 F(fr)72 537.6 Q(om)-.18 E F4
(bash.CWRU.Edu:/pub/bash.)2.5 E F0 1.207(The Fr)97 553.2 R 1.207(ee Softwar)
-.18 F 3.707(eF)-.18 G 1.207
(oundation sells tapes and CD-ROMs containing Bash; send electr)188.531 553.2 R
(onic)-.18 E(mail to)72 565.2 Q F3(gnu@prep.ai.mit.edu)2.5 E F0(or call)2.5 E
F3(+1-617-876-3296)2.5 E F0(for mor)2.5 E 2.5(ei)-.18 G(nformation.)387.54
565.2 Q .283(Bash is also distributed with several versions of)97 580.8 R F2
(UNIX)2.782 E F0 .282(-compatible systems.)B .282(It is included as)5.282 F
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3.124(ea)-.18 G .624(bout the dif)353.78 592.8 R(fer)-.18 E .624
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2.5(nB)200.83 604.8 S(SDI's BSD/386* and Fr)215.26 604.8 Q(eeBSD.)-.18 E .529
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136.364 632.4 R(`normal')-.37 E 2.538('c)-.37 G .038
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(eatur)456.022 632.4 Q .038(es ar)-.18 F(e)-.18 E .451(included, and a `)72
644.4 R(`minimal')-.37 E 2.951('c)-.37 G .451
(on\214guration, which omits job contr)199.384 644.4 R .451
(ol, aliases, history and command)-.18 F .356(line editing, the dir)72 656.4 R
.356(ectory stack and)-.18 F F1(pushd/popd/dirs,)2.856 E F0(pr)2.856 E .357
(ocess substitution, pr)-.18 F .357(ompt string special)-.18 F .32 LW 76 666.4
72 666.4 DL 80 666.4 76 666.4 DL 84 666.4 80 666.4 DL 88 666.4 84 666.4 DL 92
666.4 88 666.4 DL 96 666.4 92 666.4 DL 100 666.4 96 666.4 DL 104 666.4 100
666.4 DL 108 666.4 104 666.4 DL 112 666.4 108 666.4 DL 116 666.4 112 666.4 DL
120 666.4 116 666.4 DL 124 666.4 120 666.4 DL 128 666.4 124 666.4 DL 132 666.4
128 666.4 DL 136 666.4 132 666.4 DL 140 666.4 136 666.4 DL 144 666.4 140 666.4
DL/F5 8/Palatino-Roman@0 SF .42(\207S. R. Bourne, `)72 676.4 R .42(`UNIX T)
-.296 F .42(ime-Sharing System:)-.44 F .42(The UNIX Shell')4.42 F(',)-.296 E/F6
8/Palatino-Italic@0 SF .42(Bell System T)2.42 F .42(echnical Journal)-.888 F F5
2.42(,5)C .42(7\(6\), July-August,)405.004 676.4 R(1978, pp. 1971-1990.)72
686.4 Q<8854>72 696.4 Q .209(om Duf)-.736 F .209(f, `)-.144 F .209
(`Rc \255 A Shell for Plan 9 and)-.296 F/F7 7/Palatino-Roman@0 SF(UNIX)2.209 E
F5(systems')2.209 E(',)-.296 E F6(Pr)2.209 E .208
(oc. of the Summer 1990 EUUG Confer)-.144 F(ence)-.144 E F5 2.208(,L)C .208
(ondon, Ju-)430.704 696.4 R(ly)72 706.4 Q 2(,1)-.888 G(990, pp. 21-33.)85.888
706.4 Q(*BSD/386 is a trademark of Berkeley Softwar)72 716.4 Q 2(eD)-.144 G
(esign, Inc.)243.472 716.4 Q EP
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/F0 10/Palatino-Roman@0 SF 2.5(-1)277.17 48 S 2.5(2-)288 48 S 1.319
(character decoding, and the)72 84 R/F1 10/Palatino-Italic@0 SF(select)3.818 E
F0(constr)5.484 E 3.818(uct. This)-.08 F 1.318
(minimal version is designed to be a dr)3.818 F(op-in)-.18 E -.18(re)72 96 S
1.292(placement for the traditional).18 F/F2 9/Palatino-Roman@0 SF(UNIX)3.792 E
F0 1.293(/bin/sh, and is included as the Linux /bin/sh in several)3.792 F
(packagings.)72 108 Q/F3 10/Palatino-Bold@0 SF 2.5(8. Conclusion)72 132 R F0
.19(Bash is a worthy successor to sh.)97 147.6 R .19(It is suf)5.19 F .19
(\214ciently portable to r)-.18 F .19(un on nearly every version of)-.08 F F2
(UNIX)72 159.6 Q F0(fr)2.929 E .429(om 4.3 BSD to SVR4.2, and several)-.18 F F2
(UNIX)2.93 E F0 2.93(workalikes. It)2.93 F .43(is r)2.93 F .43
(obust enough to r)-.18 F .43(eplace sh on)-.18 F 1.22
(most of those systems, and pr)72 171.6 R 1.219(ovides mor)-.18 F 3.719(ef)-.18
G(unctionality)271.896 171.6 Q 6.219(.I)-1.11 G 3.719(th)336.255 171.6 S 1.219
(as several thousand r)349.054 171.6 R 1.219(egular users,)-.18 F .052(and the\
ir feedback has helped to make it as good as it is today \255 a testament to t\
he bene\214ts of fr)72 183.6 R(ee)-.18 E(softwar)72 195.6 Q(e.)-.18 E EP
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