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(there are rumors of ports to DOS and W)72 361.8 R(indo)-.4 E .706
(ws NT)-.25 F 5.706(.P)-.74 G .706(orts to)-5.706 F F5(UNIX)3.206 E F3
(-lik)A 3.206(es)-.1 G .706(ystems such as QNX and Minix)-3.206 F
(are part of the distrib)72 373.8 Q(ution.)-.2 E .405
(The original author of Bash w)97 389.4 R .405(as Brian F)-.1 F .405
(ox, an emplo)-.15 F .405(yee of the Free Softw)-.1 F .405(are F)-.1 F
2.905(oundation. The)-.15 F(cur)2.905 E(-)-.2 E(rent de)72 401.4 Q -.15
(ve)-.25 G(loper and maintainer is Chet Rame).15 E 1.3 -.65(y, a v)-.15
H(olunteer who w).45 E(orks at Case W)-.1 E(estern Reserv)-.8 E 2.5(eU)
-.15 G(ni)-2.5 E -.15(ve)-.25 G(rsity).15 E(.)-.65 E F2 2.5(2. What')72
425.4 R 2.5(sP)-.37 G(OSIX, anyway?)-2.5 E F1(POSIX)97 441 Q F3 .343
(is a name originally coined by Richard Stallman for a f)2.843 F .343
(amily of open system standards based)-.1 F(on)72 453 Q F5(UNIX)3.24 E
F3 5.74(.T)C .74(here are a number of aspects of)-5.74 F F5(UNIX)3.24 E
F3 .74(under consideration for standardization, from the basic)3.24 F
.192(system services at the system call and C library le)72 465 R -.15
(ve)-.25 G 2.692(lt).15 G 2.692(oa)-2.692 G .192
(pplications and tools to system administration and)-2.692 F 2.5
(management. Each)72 477 R(area of standardization is assigned to a w)
2.5 E(orking group in the 1003 series.)-.1 E 2.814
(The POSIX Shell and Utilities standard has been de)97 492.6 R -.15(ve)
-.25 G 2.814(loped by IEEE W).15 F 2.813(orking Group 1003.2)-.8 F .254
(\(POSIX.2\).\210 It concentrates on the command interpreter interf)72
504.6 R .253(ace and utility programs commonly e)-.1 F -.15(xe)-.15 G
(cuted).15 E 1.112(from the command line or by other programs.)72 516.6
R 1.112(An initial v)6.112 F 1.113
(ersion of the standard has been appro)-.15 F -.15(ve)-.15 G 3.613(da)
.15 G(nd)-3.613 E .365(published by the IEEE, and w)72 528.6 R .365
(ork is currently underw)-.1 F .365(ay to update it.)-.1 F .365
(There are four primary areas of w)5.365 F(ork)-.1 E
(in the 1003.2 standard:)72 540.6 Q 21.5<8341>72 556.2 S .835
(spects of the shell')-21.5 F 3.335(ss)-.55 G .835
(yntax and command language.)-3.335 F 3.335(An)5.835 G .835
(umber of special b)-3.335 F .835(uiltins such as)-.2 F F2(cd)3.335 E F3
(and)3.335 E F2(exec)97 568.2 Q F3 .545(are being speci\214ed as part o\
f the shell, since their functionality usually cannot be implemented)
3.046 F(by a separate e)97 580.2 Q -.15(xe)-.15 G(cutable;).15 E 21.5
<8341>72 595.8 S .926
(set of utilities to be called by shell scripts and applications.)
-18.074 F .927(Examples are programs lik)5.927 F(e)-.1 E F1 .927
(sed, tr)3.427 F(,)-1.11 E F3(and)97 607.8 Q F1(awk.)2.797 E F3 .297
(Utilities commonly implemented as shell b)5.297 F .296
(uiltins are described in this section, such as)-.2 F F2(test)2.796 E F3
(and)97 619.8 Q F2(kill)3.422 E F3 5.922(.A)C 3.422(ne)-5.922 G .922
(xpansion of this section')-3.572 F 3.423(ss)-.55 G .923
(cope, termed the User Portability Extension, or UPE, has)-3.423 F
(standardized interacti)97 631.8 Q .3 -.15(ve p)-.25 H(rograms such as)
.15 E F1(vi)2.5 E F3(and)2.5 E F1(mailx;)2.5 E F3 21.5<8341>72 647.4 S
.288(group of functional interf)-18.712 F .287(aces to services pro)-.1
F .287(vided by the shell, such as the traditional)-.15 F/F6 10
/Courier@0 SF(system\(\))2.787 E F3 3.289(Cl)97 659.4 S .789
(ibrary function.)-3.289 F .789(There are functions to perform shell w)
5.789 F .789(ord e)-.1 F .79(xpansions, perform \214lename e)-.15 F
(xpan-)-.15 E .324(sion \()97 671.4 R F1(globbing)A F3 .324
(\), obtain v)B .323(alues of POSIX.2 system con\214guration v)-.25 F
.323(ariables, retrie)-.25 F .623 -.15(ve v)-.25 H .323(alues of en)-.1
F(viron-)-.4 E(ment v)97 683.4 Q(ariables \()-.25 E F6(getenv\(\))A F3
(\), and other services;).833 E .32 LW 144 691.4 72 691.4 DL F4
(*An earlier v)72 703.2 Q
(ersion of this article appeared in The Linux Journal.)-.12 E(\210IEEE,)
72 715 Q/F7 8/Times-Italic@0 SF 1.231(IEEE Standar)3.231 F 3.231(df)
-.296 G 1.231(or Information T)-3.231 F(ec)-.736 E(hnolo)-.12 E 1.231
(gy -- P)-.08 F 1.231(ortable Oper)-.64 F 1.232
(ating System Interface \(POSIX\) P)-.12 F 1.232(art 2:)-.64 F
(Shell and Utilities)72 725 Q F4 2(,1)C(992.)-2 E EP
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/F0 10/Times-Roman@0 SF(-2-)282.17 48 Q 21.5<8341>72 84 S
(suite of \231de)-19 E -.15(ve)-.25 G(lopment\232 utilities such as).15
E/F1 10/Times-Italic@0 SF(c89)2.5 E F0(\(the POSIX.2 v)2.5 E(ersion of)
-.15 E F1(cc)2.5 E F0(\), and)A F1(yacc.)2.5 E F0 .483
(Bash is concerned with the aspects of the shell')97 99.6 R 2.983(sb)
-.55 G(eha)-2.983 E .484(vior de\214ned by POSIX.2.)-.2 F .484
(The shell command)5.484 F 1.439
(language has of course been standardized, including the basic \215o)72
111.6 R 3.938(wc)-.25 G 1.438(ontrol and program e)-3.938 F -.15(xe)-.15
G 1.438(cution con-).15 F 1.284
(structs, I/O redirection and pipelining, ar)72 123.6 R 1.284
(gument handling, v)-.18 F 1.284(ariable e)-.25 F 1.284
(xpansion, and quoting.)-.15 F(The)6.285 E F1(special)3.785 E F0 -.2(bu)
72 135.6 S .676
(iltins, which must be implemented as part of the shell to pro).2 F .676
(vide the desired functionality)-.15 F 3.176(,a)-.65 G .676
(re speci\214ed)-3.176 F .7(as being part of the shell; e)72 147.6 R .7
(xamples of these are)-.15 F/F2 10/Times-Bold@0 SF -2.3 -.15(ev a)3.201
H(l).15 E F0(and)3.201 E F2(export)3.201 E F0 5.701(.O)C .701
(ther utilities appear in the sections of)-5.701 F .256(POSIX.2 not de)
72 159.6 R -.2(vo)-.25 G .256(ted to the shell which are commonly \(and\
 in some cases must be\) implemented as b).2 F(uiltin)-.2 E .213
(commands, such as)72 171.6 R F2 -.18(re)2.713 G(ad).18 E F0(and)2.713 E
F2(test)2.713 E F0 5.213(.P)C .213
(OSIX.2 also speci\214es aspects of the shell')-5.213 F 2.713(si)-.55 G
(nteracti)-2.713 E .513 -.15(ve b)-.25 H(eha).15 E .214(vior as part)-.2
F .598(of the UPE, including job control and command line editing.)72
183.6 R .598(Interestingly enough, only)5.598 F F1(vi)3.098 E F0 .598
(-style line edit-)B(ing commands ha)72 195.6 Q .3 -.15(ve b)-.2 H
(een standardized;).15 E F1(emacs)2.5 E F0
(editing commands were left out due to objections.)2.5 E 1.128
(While POSIX.2 includes much of what the shell has traditionally pro)97
211.2 R 1.129(vided, some important things)-.15 F(ha)72 223.2 Q .344
-.15(ve b)-.2 H .044(een omitted as being \231be).15 F .044
(yond its scope.)-.15 F 5.043<9a54>-.7 G .043
(here is, for instance, no mention of a dif)-5.043 F .043
(ference between a)-.25 F F1(lo)72 235.2 Q(gin)-.1 E F0 1.445
(shell and an)3.945 F 3.945(yo)-.15 G 1.445(ther interacti)-3.945 F
1.745 -.15(ve s)-.25 H 1.446
(hell \(since POSIX.2 does not specify a login program\).).15 F 1.446
(No \214x)6.446 F(ed)-.15 E(startup \214les are de\214ned, either \255 \
the standard does not mention)72 247.2 Q F1(.pr)2.5 E(o\214le)-.45 E F0
(.)A F2 2.5(3. Basic)72 271.2 R(Bash featur)2.5 E(es)-.18 E F0 1.448
(Since the Bourne shell pro)97 286.8 R 1.448
(vides Bash with most of its philosophical underpinnings, Bash inherits)
-.15 F .64(most of its features and functionality from sh.)72 298.8 R
.641(Bash implements all of the traditional sh \215o)5.641 F 3.141(wc)
-.25 G .641(ontrol con-)-3.141 F .8(structs \()72 310.8 R F1(for)A F0(,)
A F1(if)3.3 E F0(,)A F1(while)3.3 E F0 3.3(,e)C 3.3(tc.\). All)-3.3 F
.799(of the Bourne shell b)3.3 F .799
(uiltins, including those not speci\214ed in the POSIX.2)-.2 F .536
(standard, appear in Bash.)72 322.8 R(Shell)5.536 E F1(functions)3.036 E
F0 3.036(,i)C .536(ntroduced in the SVR2 v)-3.036 F .537
(ersion of the Bourne shell, are similar)-.15 F .779
(to shell scripts, b)72 334.8 R .779
(ut are de\214ned using a special syntax and are e)-.2 F -.15(xe)-.15 G
.779(cuted in the same process as the calling).15 F 2.841(shell. Bash)72
346.8 R .341(has shell functions which beha)2.841 F .641 -.15(ve i)-.2 H
2.841(naf).15 G .341(ashion upw)-2.941 F .342
(ard-compatible with sh functions.)-.1 F .342(There are)5.342 F 1.447
(certain shell v)72 358.8 R 1.446
(ariables that Bash interprets in the same w)-.25 F 1.446
(ay as sh, such as)-.1 F F2(PS1)3.946 E F0(,)A F2(IFS)3.946 E F0 3.946
(,a)C(nd)-3.946 E F2 -.74(PA)3.946 G(TH)-.21 E F0 6.446(.B)C(ash)-6.446
E 1.423(implements essentially the same grammar)72 370.8 R 3.924(,p)-.4
G 1.424(arameter and v)-3.924 F 1.424(ariable e)-.25 F 1.424
(xpansion semantics, redirection, and)-.15 F 1.06
(quoting as the Bourne shell.)72 382.8 R 1.06(Where dif)6.06 F 1.06
(ferences appear between the POSIX.2 standard and traditional sh)-.25 F
(beha)72 394.8 Q(vior)-.2 E 2.5(,B)-.4 G(ash follo)-2.5 E(ws POSIX.)-.25
E 1.608(The K)97 410.4 R 1.608(orn Shell \()-.35 F F2(ksh)A F0 4.108
(\)i)C 4.108(sad)-4.108 G 1.608
(escendent of the Bourne shell written at A)-4.108 F 1.609
(T&T Bell Laboratories by)-1.11 F(Da)72 422.4 Q 1.059(vid K)-.2 F 3.559
(orn\207. It)-.35 F(pro)3.559 E 1.059
(vides a number of useful features that POSIX and Bash ha)-.15 F 1.359
-.15(ve a)-.2 H 3.558(dopted. Man).15 F 3.558(yo)-.15 G 3.558(ft)-3.558
G(he)-3.558 E(interacti)72 434.4 Q 1.312 -.15(ve f)-.25 H 1.012
(acilities in POSIX.2 ha).05 F 1.312 -.15(ve t)-.2 H 1.012
(heir roots in the ksh: for e).15 F 1.013
(xample, the POSIX and ksh job control)-.15 F -.1(fa)72 446.4 S .513
(cilities are nearly identical. Bash includes features from the K).1 F
.513(orn Shell for both interacti)-.35 F .813 -.15(ve u)-.25 H .513
(se and shell).15 F 3.905(programming. F)72 458.4 R 1.405
(or programming, Bash pro)-.15 F 1.405(vides v)-.15 F 1.405
(ariables such as)-.25 F F2(RANDOM)3.905 E F0(and)3.905 E F2(REPL)3.905
E(Y)-.92 E F0 3.905(,t)C(he)-3.905 E F2(typeset)3.905 E F0 -.2(bu)72
470.4 S .398(iltin, the ability to remo).2 F .698 -.15(ve s)-.15 H .398
(ubstrings from v).15 F .398
(ariables based on patterns, and shell arithmetic.)-.25 F F2(RANDOM)
5.397 E F0 -.15(ex)72 482.4 S .489
(pands to a random number each time it is referenced; assigning a v).15
F .49(alue to)-.25 F F2(RANDOM)2.99 E F0 .49(seeds the random)2.99 F
.055(number generator)72 494.4 R(.)-.55 E F2(REPL)5.055 E(Y)-.92 E F0
.054(is the def)2.554 F .054(ault v)-.1 F .054(ariable used by the)-.25
F F2 -.18(re)2.554 G(ad).18 E F0 -.2(bu)2.554 G .054(iltin when no v).2
F .054(ariable names are sup-)-.25 F .742(plied as ar)72 506.4 R 3.243
(guments. The)-.18 F F2(typeset)3.243 E F0 -.2(bu)3.243 G .743
(iltin is used to de\214ne v).2 F .743(ariables and gi)-.25 F 1.043 -.15
(ve t)-.25 H .743(hem attrib).15 F .743(utes such as)-.2 F F2 -.18(re)
3.243 G(ad-).18 E(only)72 518.4 Q F0 5.512(.B)C .512
(ash arithmetic allo)-5.512 F .512(ws the e)-.25 F -.25(va)-.25 G .511
(luation of an e).25 F .511
(xpression and the substitution of the result.)-.15 F .511(Shell v)5.511
F(ari-)-.25 E .222
(ables may be used as operands, and the result of an e)72 530.4 R .222
(xpression may be assigned to a v)-.15 F 2.722(ariable. Nearly)-.25 F
.222(all of)2.722 F(the operators from the C language are a)72 542.4 Q
-.25(va)-.2 G(ilable, with the same precedence rules:).25 E/F3 10
/Courier@0 SF 6($e)97 560.4 S(cho $\(\(3 + 5 * 32\)\))-6 E(163)97 572.4
Q F0 -.15(Fo)72 594 S 3.24(ri).15 G(nteracti)-3.24 E 1.04 -.15(ve u)-.25
H .74(se, Bash implements ksh-style aliases and b).15 F .74
(uiltins such as)-.2 F F2(fc)3.24 E F0 .74(\(discussed belo)3.24 F .74
(w\) and)-.25 F F2(jobs)3.24 E F0(.)A .291(Bash aliases allo)72 606 R
2.791(was)-.25 G .291(tring to be substituted for a command name.)-2.791
F(The)5.291 E 2.791(yc)-.15 G .291(an be used to create a mnemonic)
-2.791 F .568(for a)72 618 R/F4 9/Times-Roman@0 SF(UNIX)3.068 E F0 .568
(command name \()3.068 F F3 .568(alias del=rm)B F0 .568(\), to e)B .567
(xpand a single w)-.15 F .567(ord to a comple)-.1 F 3.067(xc)-.15 G .567
(ommand \()-3.067 F F3(alias)A .255
(news='xterm -g 80x45 -title trn -e trn -e -S1 -N &')72 630 R F0 .255
(\), or to ensure that a command)B(is in)72 642 Q -.2(vo)-.4 G -.1(ke).2
G 2.5(dw).1 G(ith a basic set of options \()-2.5 E F3
(alias ls="/bin/ls -F")A F0(\).)A .293(The C shell \()97 657.6 R F2(csh)
A F0 .293(\)\207, originally written by Bill Jo)B 2.792(yw)-.1 G .292
(hile at Berk)-2.792 F(ele)-.1 E 1.592 -.65(y, i)-.15 H 2.792(sw).65 G
.292(idely used and quite popular)-2.792 F 1.499(for its interacti)72
669.6 R 1.799 -.15(ve f)-.25 H 3.999(acilities. Bash).05 F 1.499
(includes a csh-compatible history e)3.999 F 1.5
(xpansion mechanism \(\231! history\232\),)-.15 F .019(brace e)72 681.6
R .018(xpansion, access to a stack of directories via the)-.15 F F2
(pushd)2.518 E F0(,)A F2(popd)2.518 E F0 2.518(,a)C(nd)-2.518 E F2(dirs)
2.518 E F0 -.2(bu)2.518 G .018(iltins, and tilde e).2 F(xpansion,)-.15 E
1.293(to generate users' home directories.)72 693.6 R -.35(Ti)6.294 G
1.294(lde e).35 F 1.294(xpansion has also been adopted by both the K)
-.15 F 1.294(orn Shell and)-.35 F .32 LW 144 708.2 72 708.2 DL/F5 8
/Times-Roman@0 SF(\207Morris Bolsk)72 720 Q 2(ya)-.12 G(nd Da)-2 E
(vid K)-.16 E(orn,)-.28 E/F6 8/Times-Italic@0 SF(The K)2 E
(ornShell Command and Pr)-.32 E -.08(og)-.36 G -.12(ra).08 G
(mming Langua).12 E -.08(ge)-.08 G F5 2(,P).08 G(rentice Hall, 1989.)-2
E EP
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/F0 10/Times-Roman@0 SF(-3-)282.17 48 Q(POSIX.2.)72 84 Q .148
(There were certain areas in which POSIX.2 felt standardization w)97
99.6 R .149(as necessary)-.1 F 2.649(,b)-.65 G .149(ut no e)-2.849 F
.149(xisting imple-)-.15 F 1.598(mentation pro)72 111.6 R 1.598
(vided the proper beha)-.15 F(vior)-.2 E 6.598(.T)-.55 G 1.598(he w)
-6.598 F 1.597(orking group in)-.1 F -.15(ve)-.4 G 1.597
(nted and standardized functionality in).15 F .674
(these areas, which Bash implements.)72 123.6 R(The)5.674 E/F1 10
/Times-Bold@0 SF(command)3.174 E F0 -.2(bu)3.174 G .674(iltin w).2 F
.674(as in)-.1 F -.15(ve)-.4 G .674
(nted so that shell functions could be).15 F .996(written to replace b)
72 135.6 R .996(uiltins; it mak)-.2 F .996(es the capabilities of the b)
-.1 F .995(uiltin a)-.2 F -.25(va)-.2 G .995(ilable to the function.).25
F .995(The reserv)5.995 F(ed)-.15 E -.1(wo)72 147.6 S 1.731
(rd \231!\232 w).1 F 1.731(as added to ne)-.1 F -.05(ga)-.15 G 1.731
(te the return v).05 F 1.731(alue of a command or pipeline; it w)-.25 F
1.732(as nearly impossible to)-.1 F -.15(ex)72 159.6 S .286
(press \231if not x\232 cleanly using the sh language.).15 F .286
(There e)5.286 F .286(xist multiple incompatible implementations of the)
-.15 F F1(test)72 171.6 Q F0 -.2(bu)3.163 G .663
(iltin, which tests \214les for type and other attrib).2 F .664
(utes and performs arithmetic and string comparisons.)-.2 F .5
(POSIX considered none of these correct, so the standard beha)72 183.6 R
.5(vior w)-.2 F .5(as speci\214ed in terms of the number of)-.1 F(ar)72
195.6 Q .412(guments to the command.)-.18 F .412(POSIX.2 dictates e)
5.412 F .412(xactly what will happen when four or fe)-.15 F .412(wer ar)
-.25 F .412(guments are)-.18 F(gi)72 207.6 Q -.15(ve)-.25 G 5.01(nt).15
G(o)-5.01 E F1(test)5.01 E F0 5.01(,a)C 2.51(nd lea)-5.01 F -.15(ve)-.2
G 5.01(st).15 G 2.51(he beha)-5.01 F 2.51(vior unde\214ned when more ar)
-.2 F 2.51(guments are supplied.)-.18 F 2.51(Bash uses the)7.51 F
(POSIX.2 algorithm, which w)72 219.6 Q(as concei)-.1 E -.15(ve)-.25 G
2.5(db).15 G 2.5(yD)-2.5 G -.2(av)-2.5 G(id K).2 E(orn.)-.35 E F1 2.5
(3.1. F)72 243.6 R(eatur)-.25 E(es not in the Bour)-.18 E(ne Shell)-.15
E F0 .718(There are a number of minor dif)97 259.2 R .719
(ferences between Bash and the v)-.25 F .719
(ersion of sh present on most other)-.15 F -.15(ve)72 271.2 S .874
(rsions of).15 F/F2 9/Times-Roman@0 SF(UNIX)3.374 E F0 5.873(.T)C .873
(he majority of these are due to the POSIX standard, b)-5.873 F .873
(ut some are the result of Bash)-.2 F .386
(adopting features from other shells.)72 283.2 R -.15(Fo)5.386 G 2.886
(ri).15 G .386(nstance, Bash includes the ne)-2.886 F 2.886<7799>-.25 G
.386(!\232 reserv)-2.886 F .386(ed w)-.15 F .386(ord, the)-.1 F F1
(command)2.886 E F0 -.2(bu)72 295.2 S .116(iltin, the ability of the).2
F F1 -.18(re)2.616 G(ad).18 E F0 -.2(bu)2.615 G .115
(iltin to correctly return a line ending with a backslash, symbolic ar)
.2 F(guments)-.18 E .798(to the)72 307.2 R F1(umask)3.298 E F0 -.2(bu)
3.298 G .798(iltin, v).2 F .798(ariable substring remo)-.25 F -.25(va)
-.15 G .798(l, a w).25 F .799(ay to get the length of a v)-.1 F .799
(ariable, and the ne)-.25 F 3.299(wa)-.25 G(lgo-)-3.299 E(rithm for the)
72 319.2 Q F1(test)2.5 E F0 -.2(bu)2.5 G
(iltin from the POSIX.2 standard, none of which appear in sh.).2 E 1.225
(Bash also implements the \231$\(...\)\232 command substitution syntax,\
 which supersedes the sh `...` con-)97 334.8 R 2.851(struct. The)72
346.8 R .351(\231$\(...\)\232 construct e)2.851 F .351(xpands to the ou\
tput of the command contained within the parentheses, with)-.15 F .664
(trailing ne)72 358.8 R .664(wlines remo)-.25 F -.15(ve)-.15 G 3.164
(d. The).15 F .664(sh syntax is accepted for backw)3.164 F .664
(ards compatibility)-.1 F 3.164(,b)-.65 G .664
(ut the \231$\(...\)\232 form is)-3.364 F(preferred because its quoting\
 rules are much simpler and it is easier to nest.)72 370.8 Q .772
(The Bourne shell does not pro)97 386.4 R .772
(vide such features as brace e)-.15 F .772
(xpansion, the ability to de\214ne a v)-.15 F(ariable)-.25 E .283
(and a function with the same name, local v)72 398.4 R .282
(ariables in shell functions, the ability to enable and disable indi-)
-.25 F .547(vidual b)72 410.4 R .547
(uiltins or write a function to replace a b)-.2 F .547
(uiltin, or a means to e)-.2 F .547
(xport a shell function to a child pro-)-.15 F(cess.)72 422.4 Q .32
(Bash has closed a long-standing shell security hole by not using the)97
438 R F1($IFS)2.82 E F0 -.25(va)2.82 G .32(riable to split each w).25 F
(ord)-.1 E 1.254(read by the shell, b)72 450 R 1.254
(ut splitting only the results of e)-.2 F 1.255
(xpansion \(ksh and the 4.4 BSD sh ha)-.15 F 1.555 -.15(ve \214)-.2 H
-.15(xe).15 G 3.755(dt).15 G 1.255(his as)-3.755 F 2.907(well\). Useful)
72 462 R(beha)2.907 E .407(vior such as a means to abort e)-.2 F -.15
(xe)-.15 G .407(cution of a script read with the \231.).15 F 2.906<9a63>
-.7 G .406(ommand using the)-2.906 F F1 -.18(re)72 474 S(tur).18 E(n)
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(In addition to the basic commands and k)6.69 F 1.991 -.15(ey b)-.1 H
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(If there is only one possible completion, the rest of the)5.523 F .358
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(vide speci\214c types of completion before the def)-.15 F .483
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(This is quite \215e)5.132 F .132
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(ords, shell functions, and)-.1 F -.15(exe)72 506.4 S .424
(cutables found in the \214le system\), shell v).15 F .424
(ariables, usernames, and hostnames.)-.25 F .423
(It uses a set of heuristics)5.424 F(that, while not perfect, is genera\
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518.4 Q F1 2.5(4.4. History)72 542.4 R F0 .144
(Access to the list of commands pre)97 558 R .144(viously entered \(the)
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(iltins to manipulate the history list.).2 F .391(The v)5.391 F .391
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(command can read or write \214les containing the history list and dis-)
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(cho a{d,c,b}e)-6 E(ade ace abe)97 514.8 Q F0 .306(As this e)72 536.4 R
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(re by \214lename e)-2.805 F(xpan-)-.15 E(sion.)72 548.4 Q F2 2.5
(4.7. Pr)72 572.4 R(ocess Substitution)-.18 E F0 .457
(On systems that can support it, Bash pro)97 588 R .457(vides a f)-.15 F
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(stitution is similar to command substitution in that its speci\214cati\
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2.681(so)-.55 G .181(utput and insert it into the command line.)-2.681 F
(Rather)5.181 E 2.681(,B)-.4 G .182(ash opens a pipe)-2.681 F 1.861
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(The shell uses named pipes \(FIFOs\) or the)6.861 F F3(/de)4.361 E
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(This \214lename becomes the result of the e)5.104 F 2.603
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(pare the outputs of tw)72 660 Q 2.5(od)-.1 G(if)-2.5 E(ferent v)-.25 E
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(One of the most signi\214cant impro)97 301.2 R -.15(ve)-.15 G .145
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(introduced changes to readline that made it eight-bit clean as well.)72
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(is accepted as well, to be compatible with some older GNU utilities.)
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(alue of)-.25 F F3($ENV)3.007 E F0 .507(rather than the \231nor)3.007 F
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(under consideration for future releases.)72 620.4 R .242
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.918(ault k)-.1 F 1.218 -.15(ey b)-.1 H 3.418(indings. A).15 F(ne)3.418
E 3.418(wh)-.25 G .919(istory search mode has been implemented: in this\
 mode, readline searches)-3.418 F .336(the history for lines be)72 108 R
.336(ginning with the characters between the be)-.15 F .336
(ginning of the current line and the cursor)-.15 F(.)-.55 E .555(The e)
72 120 R .556(xisting readline incremental search commands no longer ma\
tch identical lines more than once.)-.15 F(File-)5.556 E 1.979
(name completion no)72 132 R 4.479(we)-.25 G 1.979(xpands v)-4.629 F
1.979(ariables in directory names.)-.25 F 1.978(The history e)6.978 F
1.978(xpansion f)-.15 F 1.978(acilities are no)-.1 F(w)-.25 E 1.449
(nearly completely csh-compatible: missing modi\214ers ha)72 144 R 1.749
-.15(ve b)-.2 H 1.449(een added and history substitution has been).15 F
-.15(ex)72 156 S(tended.).15 E(Se)97 171.6 Q -.15(ve)-.25 G .474
(ral of the features described earlier).15 F 2.973(,s)-.4 G .473(uch as)
-2.973 F/F1 10/Times-Bold@0 SF .473(set -o posix)2.973 F F0(and)2.973 E
F1($POSIX_PED)2.973 E(ANTIC)-.35 E F0 2.973(,a)C .473(re ne)-2.973 F
2.973(wi)-.25 G(n)-2.973 E -.15(ve)72 183.6 S .106(rsion 1.14.).15 F
.106(There is a ne)5.106 F 2.606(ws)-.25 G .106(hell v)-2.606 F
(ariable,)-.25 E F1(OSTYPE)2.606 E F0 2.606(,t)C 2.606(ow)-2.606 G .106
(hich Bash assigns a v)-2.606 F .106(alue that identi\214es the v)-.25 F
(er)-.15 E(-)-.2 E 1.38(sion of)72 195.6 R/F2 9/Times-Roman@0 SF(UNIX)
3.88 E F0(it')3.88 E 3.879(sr)-.55 G 1.379(unning on \(great for puttin\
g architecture-speci\214c binary directories into the)-3.879 F F1($P)
3.879 E -.95(AT)-.74 G(H).95 E F0(\).)A -1 -.8(Tw o)72 207.6 T -.25(va)
6.215 G 2.915(riables ha).25 F 3.215 -.15(ve b)-.2 H 2.915(een renamed:)
.15 F F1($HISTCONTR)5.416 E(OL)-.3 E F0(replaces)5.416 E F1
($history_contr)5.416 E(ol)-.18 E F0 5.416(,a)C(nd)-5.416 E F1
($HOSTFILE)5.416 E F0(replaces)72 219.6 Q F1
($hostname_completion_\214le)2.521 E F0 5.021(.I)C 2.521(nb)-5.021 G
.021(oth cases, the old names are accepted for backw)-2.521 F .02
(ards compatibil-)-.1 F(ity)72 231.6 Q 5.788(.T)-.65 G .788(he ksh)
-5.788 F/F3 10/Times-Italic@0 SF(select)3.288 E F0 .788
(construct, which allo)3.288 F .788
(ws the generation of simple menus, has been implemented.)-.25 F(Ne)
5.788 E(w)-.25 E 1.496(capabilities ha)72 243.6 R 1.796 -.15(ve b)-.2 H
1.496(een added to e).15 F 1.495(xisting v)-.15 F(ariables:)-.25 E F1
($auto_r)3.995 E(esume)-.18 E F0 1.495(can no)3.995 F 3.995(wt)-.25 G
(ak)-3.995 E 3.995(ev)-.1 G 1.495(alues of)-4.245 F F3 -.2(ex)3.995 G
(act).2 E F0(or)3.995 E F3(sub-)3.995 E(string)72 255.6 Q F0 4.843(,a)C
(nd)-4.843 E F1($HISTCONTR)4.843 E(OL)-.3 E F0 2.343(understands the v)
4.843 F(alue)-.25 E F3(ignor)4.844 E(eboth)-.37 E F0 4.844(,w)C 2.344
(hich combines the tw)-4.844 F 4.844(op)-.1 G(re)-4.844 E(viously)-.25 E
1.556(acceptable v)72 267.6 R 4.056(alues. The)-.25 F F1(dirs)4.056 E F0
-.2(bu)4.056 G 1.556(iltin has acquired options to print out speci\214c\
 members of the directory).2 F 3.062(stack. The)72 279.6 R F1($nolinks)
3.062 E F0 -.25(va)3.062 G .562(riable, which forces a ph).25 F .562
(ysical vie)-.05 F 3.062(wo)-.25 G 3.062(ft)-3.062 G .563
(he \214le system, has been superseded by the)-3.062 F F1<ad50>72 291.6
Q F0 .494(option to the)2.994 F F1(set)2.994 E F0 -.2(bu)2.994 G .494
(iltin \(equi).2 F -.25(va)-.25 G .494(lent to).25 F F1 .494(set -o ph)
2.994 F(ysical)-.15 E F0 .493(\); the v)B .493
(ariable is retained for backw)-.25 F .493(ards compati-)-.1 F(bility)72
303.6 Q 5.196(.T)-.65 G .196(he v)-5.196 F .196
(ersion string contained in)-.15 F F1($B)2.696 E(ASH_VERSION)-.3 E F0
(no)2.696 E 2.696(wi)-.25 G .196(ncludes an indication of the patch le)
-2.696 F -.15(ve)-.25 G 2.696(la).15 G(s)-2.696 E .85(well as the \231b)
72 315.6 R .85(uild v)-.2 F 3.35(ersion\232. Some)-.15 F .85
(little-used features ha)3.35 F 1.15 -.15(ve b)-.2 H .85(een remo).15 F
-.15(ve)-.15 G 3.35(d: the).15 F F1(by)3.35 E(e)-.1 E F0(synon)3.35 E
.85(ym for)-.15 F F1(exit)3.35 E F0(and)3.35 E(the)72 327.6 Q F1($NO_PR)
3.498 E(OMPT_V)-.3 E(ARS)-1.35 E F0 -.25(va)3.498 G .998
(riable are gone.).25 F .998(There is no)5.998 F 3.498(wa)-.25 G 3.498
(no)-3.498 G -2.19 -.18(rg a)-3.498 H .998
(nized test suite that can be run as a).18 F(re)72 339.6 Q
(gression test when b)-.15 E(uilding a ne)-.2 E 2.5(wv)-.25 G
(ersion of Bash.)-2.65 E 1.696(The documentation has been thoroughly o)
97 355.2 R -.15(ve)-.15 G 1.696(rhauled: there is a ne).15 F 4.196(wm)
-.25 G 1.695(anual page on the readline)-4.196 F .467(library and the)72
367.2 R F3(info)2.967 E F0 .467
(\214le has been updated to re\215ect the current v)2.967 F 2.968
(ersion. As)-.15 F(al)2.968 E -.1(wa)-.1 G .468(ys, as man).1 F 2.968
(yb)-.15 G .468(ugs as possi-)-3.168 F(ble ha)72 379.2 Q .3 -.15(ve b)
-.2 H(een \214x).15 E(ed, although some surely remain.)-.15 E F1 2.5
(5.2. Other)72 403.2 R -.25(Fe)2.5 G(atur).25 E(es)-.18 E F0 1.68
(There are a fe)97 418.8 R 4.18(wf)-.25 G 1.68
(eatures that I hope to include in later Bash releases.)-4.18 F 1.68
(Some are based on w)6.68 F(ork)-.1 E(already done in other shells.)72
430.8 Q .958(In addition to simple v)97 446.4 R .959(ariables, a future\
 release of Bash will include one-dimensional arrays, using)-.25 F .206
(the ksh implementation of arrays as a model.)72 458.4 R .205
(Additions to the ksh syntax, such as)5.205 F F3(varname)2.705 E F0 .205
(=\( ... \) to assign)B 2.587(al)72 470.4 S .087(ist of w)-2.587 F .088
(ords directly to an array and a mechanism to allo)-.1 F 2.588(wt)-.25 G
(he)-2.588 E F1 -.18(re)2.588 G(ad).18 E F0 -.2(bu)2.588 G .088
(iltin to read a list of v).2 F .088(alues directly)-.25 F .092
(into an array)72 482.4 R 2.592(,w)-.65 G .092(ould be desirable.)-2.692
F(Gi)5.092 E -.15(ve)-.25 G 2.592(nt).15 G .092(hose e)-2.592 F .092
(xtensions, the ksh)-.15 F F1 .092(set \255A)2.592 F F0 .091
(syntax may not be w)2.591 F .091(orth support-)-.1 F(ing \(the)72 494.4
Q F1<ad41>2.5 E F0(option assigns a list of v)2.5 E(alues to an array)
-.25 E 2.5(,b)-.65 G(ut is a rather peculiar special case\).)-2.7 E .76
(Some shells include a means of)97 510 R F3(pr)3.26 E -.1(og)-.45 G -.15
(ra).1 G(mmable).15 E F0 -.1(wo)3.26 G .76
(rd completion, where the user speci\214es on a per).1 F(-)-.2 E .163
(command basis ho)72 522 R 2.663(wt)-.25 G .163(he ar)-2.663 F .163(gum\
ents of the command are to be treated when completion is attempted: as \
\214le-)-.18 F .194(names, hostnames, e)72 534 R -.15(xe)-.15 G .194
(cutable \214les, and so on.).15 F .195
(The other aspects of the current Bash implementation could)5.195 F .482
(remain as-is; the e)72 546 R .482(xisting heuristics w)-.15 F .481
(ould still be v)-.1 F 2.981(alid. Only)-.25 F .481
(when completing the ar)2.981 F .481(guments to a simple)-.18 F
(command w)72 558 Q(ould the programmable completion be in ef)-.1 E
(fect.)-.25 E .479(It w)97 573.6 R .479(ould also be nice to gi)-.1 F
.779 -.15(ve t)-.25 H .479(he user \214ner).15 F .479
(-grained control o)-.2 F -.15(ve)-.15 G 2.98(rw).15 G .48
(hich commands are sa)-2.98 F -.15(ve)-.2 G 2.98(do).15 G .48(nto the)
-2.98 F 1.786(history list.)72 585.6 R 1.786(One proposal is for a v)
6.786 F 1.786(ariable, tentati)-.25 F -.15(ve)-.25 G 1.786(ly named).15
F F1(HISTIGNORE)4.286 E F0 4.285(,w)C 1.785(hich w)-4.285 F 1.785
(ould contain a)-.1 F .496(colon-separated list of commands.)72 597.6 R
.496(Lines be)5.496 F .496
(ginning with these commands, after the restrictions of)-.15 F F1($HIST)
2.997 E(-)-.92 E(CONTR)72 609.6 Q(OL)-.3 E F0(ha)2.65 E .45 -.15(ve b)
-.2 H .15(een applied, w).15 F .15
(ould not be placed onto the history list.)-.1 F .15
(The shell pattern-matching capa-)5.15 F(bilities could also be a)72
621.6 Q -.25(va)-.2 G(ilable when specifying the contents of).25 E F1
($HISTIGNORE)2.5 E F0(.)A .729(One thing that ne)97 637.2 R .729
(wer shells such as)-.25 F F1(wksh)3.229 E F0 .729(\(also kno)3.229 F
.729(wn as)-.25 F F1(dtksh)3.23 E F0 3.23(\)p)C(ro)-3.23 E .73
(vide is a command to dynami-)-.15 F 1.189
(cally load code implementing additional b)72 649.2 R 1.189
(uiltin commands into a running shell.)-.2 F 1.188(This ne)6.188 F 3.688
(wb)-.25 G 1.188(uiltin w)-3.888 F(ould)-.1 E(tak)72 661.2 Q 2.875(ea)
-.1 G 2.875(no)-2.875 G .375
(bject \214le or shared library implementing the \231body\232 of the b)
-2.875 F .375(uiltin \()-.2 F F3(xxx_b)A(uiltin\(\))-.2 E F0 .375
(for those f)2.875 F(amiliar)-.1 E .052
(with Bash internals\) and a structure containing the name of the ne)72
673.2 R 2.552(wc)-.25 G .051(ommand, the function to call when the)
-2.552 F(ne)72 685.2 Q 3.458(wb)-.25 G .958(uiltin is in)-3.658 F -.2
(vo)-.4 G -.1(ke).2 G 3.458(d\().1 G .959
(presumably de\214ned in the shared object speci\214ed as an ar)-3.458 F
.959(gument\), and the docu-)-.18 F 1.352
(mentation to be printed by the)72 697.2 R F1(help)3.851 E F0 1.351
(command \(possibly present in the shared object as well\).)3.851 F
1.351(It w)6.351 F(ould)-.1 E(manage the details of e)72 709.2 Q
(xtending the internal table of b)-.15 E(uiltins.)-.2 E EP
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/F0 10/Times-Roman@0 SF(-10-)279.67 48 Q 3.291(Af)97 84 S 1.291 -.25
(ew o)-3.291 H .791(ther b).25 F .791(uiltins w)-.2 F .791
(ould also be desirable: tw)-.1 F 3.291(oa)-.1 G .791(re the POSIX.2)
-3.291 F/F1 10/Times-Bold@0 SF(getconf)3.292 E F0 .792
(command, which prints)3.292 F 1.412(the v)72 96 R 1.412
(alues of system con\214guration v)-.25 F 1.411
(ariables de\214ned by POSIX.2, and a)-.25 F F1(diso)3.911 E(wn)-.1 E F0
-.2(bu)3.911 G 1.411(iltin, which causes a).2 F 1.347
(shell running with job control acti)72 108 R 1.647 -.15(ve t)-.25 H
3.847<6f99>.15 G(for)-3.847 E 1.347
(get about\232 one or more background jobs in its internal jobs)-.18 F
3.465(table. Using)72 120 R F1(getconf)3.465 E F0 3.465(,f)C .965(or e)
-3.465 F .965(xample, a user could retrie)-.15 F 1.264 -.15(ve a v)-.25
H .964(alue for)-.1 F F1($P)3.464 E -.95(AT)-.74 G(H).95 E F0 .964
(guaranteed to \214nd all of the)3.464 F .884
(POSIX standard utilities, or \214nd out ho)72 132 R 3.385(wl)-.25 G
.885
(ong \214lenames may be in the \214le system containing a speci\214ed)
-3.385 F(directory)72 144 Q(.)-.65 E 1.521
(There are no implementation timetables for an)97 159.6 R 4.021(yo)-.15
G 4.021(ft)-4.021 G 1.52(hese features, nor are there concrete plans to)
-4.021 F(include them.)72 171.6 Q(If an)5 E(yone has comments on these \
proposals, feel free to send me electronic mail.)-.15 E F1 2.5
(6. Re\215ections)72 195.6 R(and Lessons Lear)2.5 E(ned)-.15 E F0 .433
(The lesson that has been repeated most often during Bash de)97 211.2 R
-.15(ve)-.25 G .433(lopment is that there are dark corners).15 F .181
(in the Bourne shell, and people use all of them.)72 223.2 R .18
(In the original description of the Bourne shell, quoting and)5.181 F
.073(the shell grammar are both poorly speci\214ed and incomplete; subs\
equent descriptions ha)72 235.2 R .373 -.15(ve n)-.2 H .073
(ot helped much.).15 F 1.856(The grammar presented in Bourne')72 247.2 R
4.356(sp)-.55 G 1.856(aper describing the shell distrib)-4.356 F 1.855
(uted with the Se)-.2 F -.15(ve)-.25 G 1.855(nth Edition of).15 F/F2 9
/Times-Roman@0 SF(UNIX)72 259.2 Q F0 2.5<8769>C 2.5(ss)-2.5 G 2.5(of)
-2.5 G(ar of)-2.6 E 2.5(ft)-.25 G(hat it does not allo)-2.5 E 2.5(wt)
-.25 G(he command)-2.5 E/F3 10/Courier@0 SF(who|wc)2.5 E F0 5(.I)C 2.5
(nf)-5 G(act, as T)-2.6 E(om Duf)-.8 E 2.5(fs)-.25 G(tates:)-2.5 E 1.375
(Nobody really kno)97 274.8 R 1.375(ws what the Bourne shell')-.25 F
3.875(sg)-.55 G 1.375(rammar is.)-3.875 F(Ev)6.376 E 1.376(en e)-.15 F
1.376(xamination of the source)-.15 F(code is little help.\210)97 286.8
Q .382(The POSIX.2 standard includes a)72 302.4 R/F4 10/Times-Italic@0
SF(yacc)2.882 E F0 .382
(grammar that comes close to capturing the Bourne shell')2.882 F 2.882
(sb)-.55 G(eha)-2.882 E(vior)-.2 E(,)-.4 E -.2(bu)72 314.4 S 3.246(ti).2
G 3.246(td)-3.246 G(isallo)-3.246 E .747(ws some constructs which sh ac\
cepts without complaint \255 and there are scripts out there that)-.25 F
.501(use them.)72 326.4 R .501(It took a fe)5.501 F 3.001(wv)-.25 G .501
(ersions and se)-3.151 F -.15(ve)-.25 G .501(ral b).15 F .5
(ug reports before Bash implemented sh-compatible quoting,)-.2 F .279
(and there are still some \231le)72 338.4 R -.05(ga)-.15 G .279
(l\232 sh constructs which Bash \215ags as syntax errors.).05 F .28
(Complete sh compatibility)5.28 F(is a tough nut.)72 350.4 Q 1.231
(The shell is bigger and slo)97 366 R 1.231(wer than I w)-.25 F 1.231
(ould lik)-.1 F 1.23(e, though the current v)-.1 F 1.23
(ersion is substantially f)-.15 F(aster)-.1 E .086(than pre)72 378 R
(viously)-.25 E 5.086(.T)-.65 G .087
(he readline library could stand a substantial re)-5.086 F 2.587
(write. A)-.25 F .087(hand-written parser to replace the)2.587 F
(current)72 390 Q F4(yacc)2.978 E F0 .478(-generated one w)B .477
(ould probably result in a speedup, and w)-.1 F .477(ould solv)-.1 F
2.977(eo)-.15 G .477(ne glaring problem:)-2.977 F(the)5.477 E .384
(shell could parse commands in \231$\(...\)\232 constructs as the)72 402
R 2.884(ya)-.15 G .385
(re entered, rather than reporting errors when the)-2.884 F
(construct is e)72 414 Q(xpanded.)-.15 E 1.064(As al)97 429.6 R -.1(wa)
-.1 G 1.064(ys, there is some chaf).1 F 3.564(ft)-.25 G 3.564(og)-3.564
G 3.564(ow)-3.564 G 1.064(ith the wheat.)-3.564 F 1.063
(Areas of duplicated functionality need to be)6.063 F .382(cleaned up.)
72 441.6 R .382(There are se)5.382 F -.15(ve)-.25 G .382
(ral cases where Bash treats a v).15 F .382
(ariable specially to enable functionality a)-.25 F -.25(va)-.2 G
(ilable).25 E .185(another w)72 453.6 R .185(ay \()-.1 F F1($notify)A F0
(vs.)2.684 E F1 .184(set -o notify)5.184 F F0(and)2.684 E F1($nolinks)
2.684 E F0(vs.)2.684 E F1 .184(set -o ph)2.684 F(ysical)-.15 E F0 2.684
(,f)C .184(or instance\); the special treatment)-2.684 F 3.421(of the v)
72 465.6 R 3.421(ariable name should probably be remo)-.25 F -.15(ve)
-.15 G 5.921(d. A).15 F(fe)5.921 E 5.921(wm)-.25 G 3.422
(ore things could stand remo)-5.921 F -.25(va)-.15 G 3.422(l; the).25 F
F1($allo)72 477.6 Q(w_null_glob_expansion)-.1 E F0(and)4.112 E F1
($glob_dot_\214lenames)4.112 E F0 -.25(va)4.111 G 1.611
(riables are of particularly questionable v).25 F(alue.)-.25 E(The)72
489.6 Q F1($[...])3.977 E F0 1.477(arithmetic e)3.977 F -.25(va)-.25 G
1.478(luation syntax is redundant no).25 F 3.978(wt)-.25 G 1.478
(hat the POSIX-mandated)-3.978 F F1($\(\(...\)\))3.978 E F0 1.478
(construct has)3.978 F .326(been implemented, and could be deleted.)72
501.6 R .326(It w)5.326 F .326(ould be nice if the te)-.1 F .326
(xt output by the)-.15 F F1(help)2.825 E F0 -.2(bu)2.825 G .325
(iltin were e).2 F(xter)-.15 E(-)-.2 E .061
(nal to the shell rather than compiled into it.)72 513.6 R .062
(The beha)5.062 F .062(vior enabled by)-.2 F F1
($command_oriented_history)2.562 E F0 2.562(,w)C(hich)-2.562 E 1.125
(causes the shell to attempt to sa)72 525.6 R 1.424 -.15(ve a)-.2 H
1.124(ll lines of a multi-line command in a single history entry).15 F
3.624(,s)-.65 G 1.124(hould be)-3.624 F(made the def)72 537.6 Q
(ault and the v)-.1 E(ariable remo)-.25 E -.15(ve)-.15 G(d.).15 E F1 2.5
(7. A)72 561.6 R -.1(va)-1 G(ilability).1 E F0 .047
(As with all other GNU softw)97 577.2 R .047(are, Bash is a)-.1 F -.25
(va)-.2 G .047(ilable for anon).25 F .047(ymous FTP from)-.15 F F4(pr)
2.547 E(ep.ai.mit.edu:/pub/gnu)-.37 E F0 1.05(and from other GNU softw)
72 589.2 R 1.05(are mirror sites.)-.1 F 1.049(The current v)6.049 F
1.049(ersion is in)-.15 F F4(bash-1.14.1.tar)3.549 E(.gz)-1.11 E F0
1.049(in that directory)3.549 F(.)-.65 E(Use)72 601.2 Q F4(ar)5.965 E
-.15(ch)-.37 G(ie).15 E F0 3.465(to \214nd the nearest archi)5.965 F
3.766 -.15(ve s)-.25 H 5.966(ite. The).15 F 3.466(latest v)5.966 F 3.466
(ersion is al)-.15 F -.1(wa)-.1 G 3.466(ys a).1 F -.25(va)-.2 G 3.466
(ilable for FTP from).25 F F4(bash.CWR)72 613.2 Q -.25(U.)-.4 G
(Edu:/pub/dist.).25 E F0(Bash documentation is a)5 E -.25(va)-.2 G
(ilable for FTP from).25 E F4(bash.CWR)2.5 E -.25(U.)-.4 G
(Edu:/pub/bash.).25 E F0 1.169(The Free Softw)97 628.8 R 1.169(are F)-.1
F 1.169(oundation sells tapes and CD-R)-.15 F 1.168
(OMs containing Bash; send electronic mail to)-.4 F F3
(gnu@prep.ai.mit.edu)72 640.8 Q F0(or call)2.5 E F3(+1-617-876-3296)2.5
E F0(for more information.)2.5 E .694(Bash is also distrib)97 656.4 R
.694(uted with se)-.2 F -.15(ve)-.25 G .694(ral v).15 F .694(ersions of)
-.15 F F2(UNIX)3.194 E F0 .694(-compatible systems.)B .695
(It is included as /bin/sh)5.694 F .948(and /bin/bash on se)72 668.4 R
-.15(ve)-.25 G .948(ral Linux distrib).15 F .948
(utions \(more about the dif)-.2 F .948
(ference in a moment\), and as contrib)-.25 F(uted)-.2 E .32 LW 144
676.4 72 676.4 DL/F5 8/Times-Roman@0 SF .781
(\207S. R. Bourne, \231UNIX T)72 688.2 R .781(ime-Sharing System:)-.28 F
.781(The UNIX Shell\232,)4.781 F/F6 8/Times-Italic@0 SF .78
(Bell System T)2.78 F(ec)-.736 E .78(hnical J)-.12 F(ournal)-.2 E F5
2.78(,5)C .78(7\(6\), July-)-2.78 F(August, 1978, pp. 1971-1990.)72
698.2 Q<8854>72 710 Q .431(om Duf)-.64 F .431
(f, \231Rc \255 A Shell for Plan 9 and)-.2 F/F7 7/Times-Roman@0 SF(UNIX)
2.432 E F5(systems\232,)2.432 E F6(Pr)2.432 E .432
(oc. of the Summer 1990 EUUG Confer)-.36 F(ence)-.296 E F5 2.432(,L)C
(on-)-2.432 E(don, July)72 720 Q 2(,1)-.52 G(990, pp. 21-33.)-2 E EP
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E 2.5(sB)-.55 G(SD/386* and FreeBSD.)-2.5 E .598(The Linux distrib)97
99.6 R .598(ution deserv)-.2 F .598(es special mention.)-.15 F .598
(There are tw)5.598 F 3.099(oc)-.1 G .599
(on\214gurations included in the stan-)-3.099 F .733(dard Bash distrib)
72 111.6 R .732(ution: a \231normal\232 con\214guration, in which all o\
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con\214guration, which omits job control, aliases, history and command \
line editing, the directory)72 123.6 R .886(stack and)72 135.6 R/F1 10
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(systems, and pro)72 223.2 R 1.515(vides more functionality)-.15 F 6.515
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-2.5 E(are.)-.1 E .32 LW 144 708.2 72 708.2 DL/F4 8/Times-Roman@0 SF
(*BSD/386 is a trademark of Berk)72 720 Q(ele)-.08 E 2(yS)-.12 G(oftw)-2
E(are Design, Inc.)-.08 E EP
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