(Access to a csh-style stack of directories)5.342 F .072(is pro)72 522 R .073(vided via the)-.15 F F1(pushd)2.573 E F0(,)A F1(popd)2.573 E F0 2.573(,a)C(nd)211.197 522 Q F1(dirs)2.573 E F0 -.2(bu)2.573 G(iltins.).2 E F1(Pushd)5.073 EF0(and)2.573 E F1(popd)2.573 E F0 .073(insert and remo)2.573 F .373 -.15(ve d)-.15 H .073(irectories from the).15 F .094(stack, respecti)72 534 R -.15(ve)-.25 G(ly).15 E 2.594(,a)-.65 G(nd)154.448 534 Q F1(dirs)2.594 E F0 .094(lists the stack contents.The)2.594 F F1(suspend)2.594 E F0 .094(command will stop the shell process when)2.594 F 1.329(job control is acti)72546 R -.15(ve)-.25 G 3.829(;m).15 G 1.329(ost other shells do not allo)169.136546 R 3.829(wt)-.25 G(hemselv)294.64 546 Q 1.33(es to be stopped lik)-.15 F3.83(et)-.1 G(hat.)421.31 546 Q F1 -.74(Ty)6.33 G(pe,).74 E F0 1.33(the bash)3.83 F(answer to)72 558 Q F1(which)2.5 E F0(and)2.5 E F1(whence,)2.5 E F0(sho)2.5 E(ws what will happen when a w)-.25 E(ord is typed as a command:)-.1 E F3 6($t)97 576 S(ype export)115 576 Q(export is a shell builtin)97 588 Q 6($t)97600 S(ype -t export)115 600 Q(builtin)97 612 Q 6($t)97 624 S(ype bash)115 624 Q(bash is /bin/bash)97 636 Q 6($t)97 648 S(ype cd)115 648 Q(cd is a function)97660 Q(cd \(\))97 672 Q({)97 684 Q(builtin cd "$@" && xtitle $HOST: $PWD)121 696Q(})97 708 Q EP%%Page: 7 7%%BeginPageSetupBP%%EndPageSetup/F0 10/Times-Roman@0 SF 2.5(-7-)279.67 48 S -1.11(Va)72 84 S .682(rious modes tell what a command w)1.11 F .681(ord is \(reserv)-.1 F .681(ed w)-.15 F .681(ord, alias, function, b)-.1 F .681(uiltin, or \214le\) or which v)-.2 F(er)-.15 E(-)-.2 E 1.15(sion of a command will be e)72 96 R -.15(xe)-.15 G1.15(cuted based on a user').15 F 3.65(ss)-.55 G 1.15(earch path.)305.7 96 R1.15(Some of this functionality has been)6.15 F(adopted by POSIX.2 and folded into the)72 108 Q/F1 10/Times-Bold@0 SF(command)2.5 E F0(utility)2.5 E(.)-.65 E F1 2.5(4.3.3. Editing)72 132 R(and Completion)2.5 E F0 .682(One area in which bash shines is command line editing.)97 147.6 R.682(Bash uses the)5.682 F/F2 10/Times-Italic@0 SF -.37(re)3.182 G(adline).37 EF0 .682(library to read and)4.848 F .102(edit lines when interacti)72 159.6 R-.15(ve)-.25 G 5.102(.R).15 G .103(eadline is a po)191.438 159.6 R .103(werful and \215e)-.25 F .103(xible input f)-.15 F .103(acility that a user can con\214gure to his)-.1 F 2.506(tastes. It)72 171.6 R(allo)2.506 E .006(ws lines to be edited using either emacs or vi commands, wh\ere those commands are appropri-)-.25 F 2.994(ate. The)72 183.6 R .494(full capability of emacs is not present \255 there is no w)2.994 F .495(ay to e)-.1 F -.15(xe)-.15 G .495(cute a named command with M-x,).15 F .222(for instance \255 b)72 195.6 R .222(ut the e)-.2 F .222(xisting commands are more than adequate.)-.15 F .221(The vi mode is compliant with the com-)5.222 F(mand line editing standardized by POSIX.2.)72 207.6 Q 1.69(Readline is fully customizable.)97 223.2 R 1.691(In addition to the basic commands and k)6.69 F 1.991 -.15(ey b)-.1 H 1.691(indings, the library).15 F(allo)72 235.2 Q .83(ws users to de\214ne additional k)-.25 F 1.13 -.15(ey b)-.1 H .83(indings using a startup \214le.).15 F(The)5.83 E F2(inputr)3.329 E(c)-.37 E F0.829(\214le, which def)4.995 F .829(aults to the)-.1 F(\214le)72 247.2 Q F2(~/.inputr)4.287 E(c)-.37 E F0 4.287(,i)1.666 G 4.287(sr)137.43 247.2 S 1.788(\ead each time readline initializes, permitting users to maintain a consistent \interf)148.937 247.2 R(ace)-.1 E .547(across a set of programs.)72 259.2 R .546(Readline includes an e)5.546 F .546(xtensible interf)-.15 F .546(ace, so each program using the library can)-.1 F .23(add its o)72 271.2 R .23(wn bindable commands and program-speci\214c k)-.25 F .531 -.15(ey b)-.1 H2.731(indings. Bash).15 F .231(uses this f)2.731 F .231(acility to add bindings)-.1 F(that perform history e)72 283.2 Q(xpansion or shell w)-.15 E(ord e)-.1 E(xpansions on the current input line.)-.15 E .707(Readline interprets a number of v)97 298.8 R .706(ariables which further tune its beha)-.25 F(vior)-.2 E 5.706(.V)-.55 G .706(ariables e)408.432 298.8 R .706(xist to control)-.15 F .157(whether or not eight-bit characters are directly read as input or con)72 310.8R -.15(ve)-.4 G .158(rted to meta-pre\214x).15 F .158(ed k)-.15 F .458 -.15(ey s)-.1 H .158(equences \(a).15 F(meta-pre\214x)72 322.8 Q 1.575(ed k)-.15 F1.875 -.15(ey s)-.1 H 1.575(equence consists of the character with the eighth bit zeroed, preceded by the).15 F F2(meta-)4.074 E(pr)72 334.8 Q(e\214x)-.37 E F0(character)4.45 E 2.784(,u)-.4 G .284(sually escape, which selects an alternate k)145.374 334.8 R -.15(ey)-.1 G .285(map\), to decide whether to output characters).15 F .485(with the eighth bit set directly or as a meta-pre\214x)72 346.8 R .485(ed k)-.15 F .784 -.15(ey s)-.1 H .484(equence, whether or not to wrap to a ne).15 F2.984(ws)-.25 G(creen)482.35 346.8 Q .157(line when a line being edited is longer than the screen width, the k)72 358.8R -.15(ey)-.1 G .158(map to which subsequent k).15 F .458 -.15(ey b)-.1 H(indings).15 E .531(should apply)72 370.8 R 3.031(,o)-.65 G 3.031(re)133.802370.8 S -.15(ve)144.353 370.8 S 3.031(nw).15 G .531(hat happens when readline w)168.894 370.8 R .531(ants to ring the terminal')-.1 F 3.03(sb)-.55 G 3.03(ell. All)399.37 370.8 R .53(of these v)3.03 F(ariables)-.25 E(can be set in the inputrc \214le.)72 382.8 Q .284(The startup \214le understands a set of C preprocessor)97 398.4 R(-lik)-.2 E2.785(ec)-.1 G .285(onditional constructs which allo)329.49 398.4 R 2.785(wv)-.25 G(ariables)472.9 398.4 Q .12(or k)72 410.4 R .42 -.15(ey b)-.1 H .119(ind\ings to be assigned based on the application using readline, the terminal curr\ently being used, or).15 F .316(the editing mode.)72 422.4 R .317(Users can add program-speci\214c bindings to mak)5.317 F 2.817(et)-.1 G .317(heir li)352.808 422.4 R -.15(ve)-.25 G 2.817(se).15 G 2.817(asier: here)396.922 422.4 R .317(are bindings to)2.817 F(edit the v)72 434.4 Q(alue of)-.25E F1 -.74(PA)2.5 G(TH)-.21 E F0(and double-quote the current or pre)2.5 E(vious w)-.25 E(ord:)-.1 E/F3 10/Courier@0 SF 6(#M)97 452.4 S(acros that are convenient for shell interaction)115 452.4 Q($if Bash)97 464.4Q 6(#e)97 476.4 S(dit the path)115 476.4 Q("\\C-xp": "PATH=${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 quotes)115 500.4Q 6(#a)97 512.4 S(nd 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\\"")97548.4 Q($endif)97 560.4 Q F0 .322(There is a readline command to re-read the \\214le, so users can edit the \214le, change some bindings, and be)72 582 R(gin)-.15 E(to use them almost immediately)72 594 Q(.)-.65 E .851(Bash implements the)97 609.6 R F1(bind)3.351 E F0 -.2(bu)3.351 G .851(iltin for more dyamic control of readline than the startup \214le permits.).2F F1(Bind)72 621.6 Q F0 .167(is used in se)2.667 F -.15(ve)-.25 G .167(ral w).15 F 2.667(ays. In)-.1 F F2(list)2.667 E F0 .167(mode, it can display the current k)4.333 F .466 -.15(ey b)-.1 H .166(indings, list all the readline edit-).15 F .149(ing directi)72 633.6 R -.15(ve)-.25 G 2.649(sa).15 G -.25(va)132.798 633.6 S .149(ilable for binding, list which k).25 F -.15(ey)-.1 G 2.649(si).15 G -1.9 -.4(nv o)282.352 633.6 T .349 -.1(ke a g).4 H -2.15 -.25(iv e).1 H 2.65(nd).25 G(irecti)345.3 633.6 Q -.15(ve)-.25 G 2.65(,o).15 G 2.65(ro)385.04 633.6 S .15(utput the current set of k)396.02 633.6 R -.15(ey)-.1 G .526(bindings in a fo\rmat that can be incorporated directly into an inputrc \214le.)72 645.6 R(In)5.526 E F2(batc)3.026 E(h)-.15 E F0 .526(mode, it reads a series)4.692 F .71(of k)72 657.6 R 1.01 -.15(ey b)-.1 H .71(indings directly from a \214le and passes them to readline.).15 F .71(In its most common usage,)5.71 F F1(bind)3.21 E F0(tak)3.21 E .71(es a)-.1 F.534(single string and passes it directly to readline, which interprets the li\ne as if it had just been read from the)72 669.6 R(inputrc \214le.)72 681.6 Q(Both k)5 E .3 -.15(ey b)-.1 H(indings and v).15 E(ariable assignments can appear in the string gi)-.25 E -.15(ve)-.25 G 2.5(nt).15 G(o)424.4 681.6 Q F1(bind)2.5 E F0(.)A .401(The readline library also pro)97 697.2 R .402(vides an interf)-.15 F .402(ace for)-.1 F F2(wor)2.902 E 2.902(dc)-.37 G(ompletion)328.546 697.2 Q F0 5.402(.W)C .402(hen the)385.888 697.2 RF2(completion)2.902 E F0(character)4.568 E 1.261(\(usually T)72 709.2 R 1.261(AB\) is typed, readline looks at the w)-.93 F 1.26(ord currently being entered and computes the set of \214le-)-.1 F .523(names of which the current w)72 721.2 R .523(ord is a v)-.1 F .523(alid pre\214x.)-.25 F .524(If there is only one possible completion, the rest of the)5.523 F EP%%Page: 8 8%%BeginPageSetupBP%%EndPageSetup/F0 10/Times-Roman@0 SF 2.5(-8-)279.67 48 S .358(characters are inserted directly)72 84 R 2.858(,o)-.65 G .358(therwise the co\mmon pre\214x of the set of \214lenames is added to the current)205.232 84 R-.1(wo)72 96 S 3.199(rd. A).1 F .699(second T)3.199 F .699(AB character entere\d immediately after a non-unique completion causes readline to list)-.93 F1.814(the possible completions; there is an option to ha)72 108 R 2.113 -.15(ve t)-.2 H 1.813(he list displayed immediately).15 F 6.813(.R)-.65 G 1.813(eadline pro)436.517 108 R(vides)-.15 E .482(hooks so that applications can pro)72 120 R .482(vide speci\214c types of completion before the def)-.15 F .483(ault \214lename completion)-.1 F .132(is attempted.)72 132 R .132(This is quite \215e)5.132 F .132(xible, though it is not completely user)-.15F 2.632(-programmable. Bash,)-.2 F .132(for e)2.632 F .132(xample, can)-.15 F.37(complete \214lenames, command names \(including aliases, b)72 144 R .37(uiltins, shell reserv)-.2 F .37(ed w)-.15 F .37(ords, shell functions, and)-.1F -.15(exe)72 156 S .424(cutables found in the \214le system\), 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 generally qui\te good at determining what type of completion to attempt.)72 168 Q/F1 10/Times-Bold@0 SF 2.5(4.3.4. History)72 192 R F0 .255(Access to the list of commands pre)97 207.6 R .255(viously entered \(the)-.25F/F2 10/Times-Italic@0 SF .255(command history)2.755 F F0 2.756(\)i)C 2.756(sp)399.236 207.6 S(ro)410.882 207.6 Q .256(vided jointly by bash)-.15 F .095(and the readline library)72 219.6 R 5.094(.B)-.65 G .094(ash pro)178.928 219.6R .094(vides v)-.15 F .094(ariables \()-.25 F F1(HISTFILE)A F0(,)A F1(HISTSIZE)2.594 E F0 2.594(,a)C(nd)382.068 219.6 Q F1(HISTCONTR)2.594 E(OL)-.3 E F0 2.594(\)a)C .094(nd the)479.186 219.6 R F1(history)72 231.6 Q F0(and)2.825 E F1(fc)2.825 E F0 -.2(bu)2.825 G .325(iltins to manipulate the history list.).2 F .325(The v)5.325 F .325(alue of)-.25 F F1(HISTFILE)2.825 E F0 .326(specifes the \214le where bash)2.826 F .128(writes the command history on e)72243.6 R .128(xit and reads it on startup.)-.15 F F1(HISTSIZE)5.128 E F0 .128(is used to limit the number of com-)2.628 F .346(mands sa)72 255.6 R -.15(ve)-.2 G 2.846(di).15 G 2.846(nt)129.002 255.6 S .346(he history)139.628 255.6 R(.)-.65 E F1(HISTCONTR)5.346 E(OL)-.3 E F0(pro)2.846 E .346(vides a crude form of control o)-.15 F -.15(ve)-.15 G 2.846(rw).15 G .346(hich commands are)425.548 255.6 R(sa)72 267.6 Q -.15(ve)-.2 G 2.905(do).15 G2.905(nt)102.325 267.6 S .405(he history list: a v)113.01 267.6 R .405(alue of)-.25 F F2(ignor)2.905 E(espace)-.37 E F0 .405(means to not sa)4.571 F .705 -.15(ve c)-.2 H .405(ommands which be).15 F .405(gin with a space; a)-.15 F -.25(va)72 279.6 S .339(lue of).25 F F2(ignor)2.839 E(edups)-.37 E F0 .339(means to not sa)4.505 F .64 -.15(ve c)-.2 H .34(ommands identical to the last command sa).15 F -.15(ve)-.2 G(d.).15 E F1(HISTCONTR)5.34 E(OL)-.3 E F0 -.1(wa)72 291.6 S 3.15(sn).1 G(amed)95.6 291.6 QF1(history_contr)3.15 E(ol)-.18 E F0 .65(in earlier v)3.15 F .649(ersions of bash; the old name is still accepted for backw)-.15 F .649(ards com-)-.1 F(patibility)72 303.6 Q 5.723(.T)-.65 G(he)121.803 303.6 Q F1(history)3.223 E F0 .724(command can read or write \214les containing the hist\ory list and display the current)3.223 F .895(list contents.)72 315.6 R(The)5.895 E F1(fc)3.395 E F0 -.2(bu)3.395 G .895(iltin, adopted from POSIX.2 and the K).2 F .894(orn Shell, allo)-.35 F .894(ws display and re-e)-.25 F -.15(xe)-.15 G(cution,).15 E .461(with optional editing, of commands from the history list.)72 327.6 R .462(The readline library of)5.462 F .462(fers a set of commands to)-.25 F .657(se\arch the history list for a portion of the current input line or a string type\d by the user)72 339.6 R 5.657(.F)-.55 G(inally)445.836 339.6 Q 3.157(,t)-.65 G(he)476.403 339.6 Q F2(his-)3.157 E(tory)72 351.6 Q F0(library)4.196 E 2.53(,g)-.65 G .03(enerally incorporated directly into the readline library)128.346351.6 R 2.53(,i)-.65 G .03(mplements a f)350.636 351.6 R .031(acility for history recall,)-.1 F -.15(ex)72 363.6 S .594(pansion, and re-e).15 F -.15(xe)-.15 G .594(cution of pre).15 F .594(vious commands v)-.25 F .594(ery similar to csh \(`)-.15 F .593(`bang history')-.74 F .593(', so called because)-.74 F(the e)72 375.6 Q(xclamation point introduces a history substitution\):)-.15 E/F3 10/Courier@0SF 6($e)97 393.6 S(cho a b c d e)115 393.6 Q 6(abcde)97 405.6 S 6($!)97 417.6 S6(!fghi)115 417.6 S(echo a b c d e f g h i)97 429.6 Q 6(abcdefghi)97 441.6 S 6($!)97 453.6 S(-2)115 453.6 Q(echo a b c d e)97 465.6 Q 6(abcde)97 477.6 S 6($e)97 489.6 S(cho !-2:1-4)115 489.6 Q(echo a b c d)97 501.6 Q 6(abcd)97 513.6S F0 1.456(The command history is only sa)72 535.2 R -.15(ve)-.2 G 3.957(dw).15G 1.457(hen the shell is interacti)232.599 535.2 R -.15(ve)-.25 G 3.957(,s).15G 3.957(oi)352.804 535.2 S 3.957(ti)364.541 535.2 S 3.957(sn)374.058 535.2 S1.457(ot a)386.905 535.2 R -.25(va)-.2 G 1.457(ilable for use by shell).25 F(scripts.)72 547.2 Q F1 2.5(4.3.5. New)72 571.2 R(Shell V)2.5 E(ariables)-.92 EF0 .701(There are a number of con)97 586.8 R -.15(ve)-.4 G .701(nience v).15 F.701(ariables that bash interprets to mak)-.25 F 3.2(el)-.1 G .7(ife easier)402.76 586.8 R 5.7(.T)-.55 G .7(hese include)453.59 586.8 R F1(FIGNORE)72 598.8Q F0 3.973(,w)C 1.473(hich is a set of \214lename suf)132.363 598.8 R<8c78>-.25E 1.474(es identifying \214les to e)-.15 F 1.474(xclude when completing \214lenames;)-.15 F F1(HOSTTYPE)72 610.8 Q F0 3.03(,w)C.53(hi