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Diffstat (limited to 'doc/FAQ')
| -rw-r--r-- | doc/FAQ | 48 |
1 files changed, 28 insertions, 20 deletions
@@ -1,4 +1,4 @@ -This is the Bash FAQ, version 2.11, for Bash version 2.02. +This is the Bash FAQ, version 2.13, for Bash version 2.02. This document contains a set of frequently-asked questions concerning Bash, the GNU Bourne-Again Shell. Bash is a freely-available command @@ -150,9 +150,10 @@ More information appears in the file `INSTALL' in the distribution. 5) Will bash run on operating systems other than Unix? Configuration specifics for Unix-like systems such as QNX and -LynxOS are included in the distribution. Previous versions of -bash have been ported to Minix, but I don't believe anyone has -built bash-2.x on Minix yet. +LynxOS are included in the distribution. Bash-2.02 should +compile and run on Minix 2.0 (patches were contributed), but I +don't believe anyone has built bash-2.x on earlier Minix versions +yet. Bash has been ported to versions of Windows implementing the Win32 programming interface. This includes Windows 95 and Windows NT. @@ -174,9 +175,9 @@ The Cygnus port works only on Intel machines. There is a port of bash ftp://ftp.gnustep.org//pub/win32/bash-alpha-nt-1.01.tar.gz -Softway Systems has ported bash-2.01.1 to their OpenNT system, a -Unix subsystem for NT that replaces the Microsoft POSIX subsystem. -Check out http://www.opennt.com for more information. +Softway Systems has ported bash-2.01.1 to their Interix (nee OpenNT) +system, a Unix subsystem for NT that replaces the Microsoft POSIX +subsystem. Check out http://www.interix.com for more information. D. J. Delorie has ported bash-1.14.7 to run under MS-DOS, as part of the DJGPP project. For more information on the project, see @@ -403,6 +404,8 @@ Things bash has that sh does not: the select compound command and reserved word new $'...' and $"..." quoting the $(...) form of command substitution + the $(<filename) form of command substitution, equivalent to + $(cat filename) the ${#param} parameter value length operator the ${!param} indirect parameter expansion operator the ${param:length[:offset]} parameter substring operator @@ -413,7 +416,7 @@ Things bash has that sh does not: TIMEFORMAT, PPID, PWD, OLDPWD, SHLVL, RANDOM, SECONDS, LINENO, HISTCMD, HOSTTYPE, OSTYPE, MACHTYPE, HOSTNAME, ENV, PS3, PS4, DIRSTACK, PIPESTATUS, HISTSIZE, HISTFILE, - HISTFILESIZE, HISTCONTROL, HISTIGNORE, GLOBIGNORE, + HISTFILESIZE, HISTCONTROL, HISTIGNORE, GLOBIGNORE, GROUPS, PROMPT_COMMAND, FCEDIT, FIGNORE, IGNOREEOF, INPUTRC, SHELLOPTS, OPTERR, HOSTFILE, TMOUT, histchars, auto_resume DEBUG trap @@ -436,6 +439,7 @@ Things bash has that sh does not: brace expansion tilde expansion arithmetic expansion with $((...)) and `let' builtin + the `[[...]]' extended conditional command process substitution aliases and alias/unalias builtins local variables in functions and `local' builtin @@ -444,9 +448,14 @@ Things bash has that sh does not: csh-like history expansion other new bash builtins: bind, command, builtin, declare/typeset, dirs, enable, fc, help, history, logout, - popd, pushd, disown, shopt + popd, pushd, disown, shopt, printf exported functions filename generation when using output redirection (command >a*) + POSIX.2-style globbing character classes + POSIX.2-style globbing equivalence classes + POSIX.2-style globbing collating symbols + egrep-like extended pattern matching operators + case-insensitive pattern matching and globbing variable assignments preceding commands affect only that command, even for builtins and functions posix mode @@ -493,7 +502,7 @@ Things bash has or uses that ksh88 does not: HISTFILESIZE, HISTIGNORE, HISTCONTROL, PROMPT_COMMAND, IGNOREEOF, FIGNORE, INPUTRC, HOSTFILE, DIRSTACK, PIPESTATUS, HOSTNAME, OPTERR, SHELLOPTS, GLOBIGNORE, - histchars, auto_resume + GROUPS, histchars, auto_resume prompt expansion with backslash escapes and command substitution redirection: &> (stdout and stderr) more extensive and extensible editing and completion @@ -504,15 +513,18 @@ Things bash has or uses that ksh88 does not: -o histexpand/-o interactive-comments/-o notify/-o physical/ -o posix/-o hashall/-o onecmd/-h/-B/-C/-b/-H/-P, set +o, suspend, trap -l, type, typeset -a/-F/-p, ulimit -u, - umask -S, alias -p, shopt, disown + umask -S, alias -p, shopt, disown, printf `!' csh-style history expansion + POSIX.2-style globbing character classes + POSIX.2-style globbing equivalence classes + POSIX.2-style globbing collating symbols + egrep-like extended pattern matching operators + case-insensitive pattern matching and globbing + `**' arithmetic operator to do exponentiation Things ksh88 has or uses that bash does not: - new version of test: [[...]] tracked aliases - $(<file) variables: ERRNO, FPATH, COLUMNS, LINES, EDITOR, VISUAL - extended pattern matching with egrep-style pattern lists co-processes (|&, >&p, <&p) weirdly-scoped functions typeset +f to list all function names without definitions @@ -547,7 +559,7 @@ New things in ksh-93 not in bash-2.02: variables: .sh.edchar, .sh.edmode, .sh.edcol, .sh.edtext, HISTEDIT, .sh.version, .sh.name, .sh.subscript, .sh.value backreferences in pattern matching - print -f (bash has a loadable version) + print -f (bash has a loadable version of print and the printf builtin) `fc' has been renamed to `hist' read -t/-d `.' can execute shell functions @@ -712,12 +724,8 @@ Most, however, can be emulated with very little trouble. ksh-88 feature Bash equivalent -------------- --------------- -[[...]] can usually use [...]; minor differences (no - pattern matching, for one) compiled-in aliases set up aliases in .bashrc; some ksh aliases are bash builtins (hash, history, type) -$(<file) $(cat file) -extended patterns no good substitute coprocesses named pipe pairs (one for read, one for write) typeset +f declare -F cd, print, whence function substitutes in examples/functions/kshenv @@ -1146,7 +1154,7 @@ is 1-56592-147-X. Look for it in fine bookstores near you. This book covers bash-1.14, but has an appendix describing some of the new features in bash-2.0. -A second edition of this book is available, just published in January, 1998. +A second edition of this book is available, published in January, 1998. The ISBN number is 1-56592-347-2. Look for it in the same fine bookstores or on the web. |