1
This is a terse description of the new features added to bash-4.3 since
2
the release of bash-4.2. As always, the manual page (doc/bash.1) is
3
the place to look for complete descriptions.
5
1. New Features in Bash
7
a. The `helptopic' completion action now maps to all the help topics, not just
10
b. The `help' builtin no longer does prefix substring matching first, so
11
`help read' does not match `readonly', but will do it if exact string
14
c. The shell can be compiled to not display a message about processes that
15
terminate due to SIGTERM.
17
d. Non-interactive shells now react to the setting of checkwinsize and set
18
LINES and COLUMNS after a foreground job exits.
20
e. There is a new shell option, `globasciiranges', which, when set to on,
21
forces globbing range comparisons to use character ordering as if they
22
were run in the C locale.
24
f. There is a new shell option, `direxpand', which makes filename completion
25
expand variables in directory names in the way bash-4.1 did.
27
g. In Posix mode, the `command' builtin does not change whether or not a
28
builtin it shadows is treated as an assignment builtin.
30
h. The `return' and `exit' builtins accept negative exit status arguments.
32
i. The word completion code checks whether or not a filename containing a
33
shell variable expands to a directory name and appends `/' to the word
34
as appropriate. The same code expands shell variables in command names
35
when performing command completion.
37
j. In Posix mode, it is now an error to attempt to define a shell function
38
with the same name as a Posix special builtin.
40
k. When compiled for strict Posix conformance, history expansion is disabled
43
l. The history expansion character (!) does not cause history expansion when
44
followed by the closing quote in a double-quoted string.
46
m. `complete' and its siblings compgen/compopt now takes a new `-o noquote'
47
option to inhibit quoting of the completions.
49
n. Setting HISTSIZE to a value less than zero causes the history list to be
50
unlimited (setting it 0 zero disables the history list).
52
o. Setting HISTFILESIZE to a value less than zero causes the history file size
53
to be unlimited (setting it to 0 causes the history file to be truncated
56
p. The `read' builtin now skips NUL bytes in the input.
58
q. There is a new `bind -X' option to print all key sequences bound to Unix
61
r. When in Posix mode, `read' is interruptible by a trapped signal. After
62
running the trap handler, read returns 128+signal and throws away any
65
s. The command completion code skips whitespace and assignment statements
66
before looking for the command name word to be completed.
68
t. The build process has a new mechanism for constructing separate help files
69
that better reflects the current set of compilation options.
71
u. The -nt and -ot options to test now work with files with nanosecond
74
v. The shell saves the command history in any shell for which history is
75
enabled and HISTFILE is set, not just interactive shells.
77
w. The shell has `nameref' variables and new -n(/+n) options to declare and
78
unset to use them, and a `test -R' option to test for them.
80
x. The shell now allows assigning, referencing, and unsetting elements of
81
indexed arrays using negative subscripts (a[-1]=2, echo ${a[-1]}) which
82
count back from the last element of the array.
84
y. The {x}<word redirection feature now allows words like {array[ind]} and
85
can use variables with special meanings to the shell (e.g., BASH_XTRACEFD).
87
z. There is a new CHILD_MAX special shell variable; its value controls the
88
number of exited child statues the shell remembers.
90
aa. There is a new configuration option (--enable-direxpand-default) that
91
causes the `direxpand' shell option to be enabled by default.
93
bb. Bash does not do anything special to ensure that the file descriptor
94
assigned to X in {x}<foo remains open after the block containing it
97
cc. The `wait' builtin has a new `-n' option to wait for the next child to
100
dd. The `printf' %(...)T format specifier now uses the current time if no
101
argument is supplied.
103
ee. There is a new variable, BASH_COMPAT, that controls the current shell
106
ff. The `popd' builtin now treats additional arguments as errors.
108
gg. The brace expansion code now treats a failed sequence expansion as a
109
simple string and will continue to expand brace terms in the remainder
112
hh. Shells started to run process substitutions now run any trap set on EXIT.
114
ii. The fc builtin now interprets -0 as the current command line.
116
jj. Completing directory names containing shell variables now adds a trailing
117
slash if the expanded result is a directory.
119
kk. `cd' has a new `-@' option to browse a file's extended attributes on
120
systems that support O_XATTR.
122
ll. The test/[/[[ `-v variable' binary operator now understands array
125
2. New Features in Readline
127
a. Readline is now more responsive to SIGHUP and other fatal signals when
128
reading input from the terminal or performing word completion but no
129
longer attempts to run any not-allowable functions from a signal handler
132
b. There are new bindable commands to search the history for the string of
133
characters between the beginning of the line and the point
134
(history-substring-search-forward, history-substring-search-backward)
136
c. Readline allows quoted strings as the values of variables when setting
137
them with `set'. As a side effect, trailing spaces and tabs are ignored
138
when setting a string variable's value.
140
d. The history library creates a backup of the history file when writing it
141
and restores the backup on a write error.
143
e. New application-settable variable: rl_filename_stat_hook: a function called
144
with a filename before using it in a call to stat(2). Bash uses it to
145
expand shell variables so things like $HOME/Downloads have a slash
148
f. New bindable function `print-last-kbd-macro', prints the most-recently-
149
defined keyboard macro in a reusable format.
151
g. New user-settable variable `colored-stats', enables use of colored text
152
to denote file types when displaying possible completions (colored analog
155
h. New user-settable variable `keyseq-timout', acts as an inter-character
156
timeout when reading input or incremental search strings.
158
i. New application-callable function: rl_clear_history. Clears the history list
159
and frees all readline-associated private data.
161
j. New user-settable variable, show-mode-in-prompt, adds a characters to the
162
beginning of the prompt indicating the current editing mode.
164
k. New application-settable variable: rl_input_available_hook; function to be
165
called when readline detects there is data available on its input file
168
l. Readline calls an application-set event hook (rl_event_hook) after it gets
169
a signal while reading input (read returns -1/EINTR but readline does not
170
handle the signal immediately) to allow the application to handle or
173
m. If the user-settable variable `history-size' is set to a value less than
174
0, the history list size is unlimited.
176
n. New application-settable variable: rl_signal_event_hook; function that is
177
called when readline is reading terminal input and read(2) is interrupted
178
by a signal. Currently not called for SIGHUP or SIGTERM.
180
o. rl_change_environment: new application-settable variable that controls
181
whether or not Readline modifies the environment (currently readline
182
modifies only LINES and COLUMNS).
184
-------------------------------------------------------------------------------
185
This is a terse description of the new features added to bash-4.2 since
186
the release of bash-4.1. As always, the manual page (doc/bash.1) is
187
the place to look for complete descriptions.
189
1. New Features in Bash
191
a. `exec -a foo' now sets $0 to `foo' in an executable shell script without a
194
b. Subshells begun to execute command substitutions or run shell functions or
195
builtins in subshells do not reset trap strings until a new trap is
196
specified. This allows $(trap) to display the caller's traps and the
197
trap strings to persist until a new trap is set.
199
c. `trap -p' will now show signals ignored at shell startup, though their
200
disposition still cannot be modified.
202
d. $'...', echo, and printf understand \uXXXX and \UXXXXXXXX escape sequences.
204
e. declare/typeset has a new `-g' option, which creates variables in the
205
global scope even when run in a shell function.
207
f. test/[/[[ have a new -v variable unary operator, which returns success if
208
`variable' has been set.
210
g. Posix parsing changes to allow `! time command' and multiple consecutive
211
instances of `!' (which toggle) and `time' (which have no cumulative
214
h. Posix change to allow `time' as a command by itself to print the elapsed
215
user, system, and real times for the shell and its children.
217
j. $((...)) is always parsed as an arithmetic expansion first, instead of as
218
a potential nested command substitution, as Posix requires.
220
k. A new FUNCNEST variable to allow the user to control the maximum shell
221
function nesting (recursive execution) level.
223
l. The mapfile builtin now supplies a third argument to the callback command:
224
the line about to be assigned to the supplied array index.
226
m. The printf builtin has a new %(fmt)T specifier, which allows time values
227
to use strftime-like formatting.
229
n. There is a new `compat41' shell option.
231
o. The cd builtin has a new Posix-mandated `-e' option.
233
p. Negative subscripts to indexed arrays, previously errors, now are treated
234
as offsets from the maximum assigned index + 1.
236
q. Negative length specifications in the ${var:offset:length} expansion,
237
previously errors, are now treated as offsets from the end of the variable.
239
r. Parsing change to allow `time -p --'.
241
s. Posix-mode parsing change to not recognize `time' as a keyword if the
242
following token begins with a `-'. This means no more Posix-mode
243
`time -p'. Posix interpretation 267.
245
t. There is a new `lastpipe' shell option that runs the last command of a
246
pipeline in the current shell context. The lastpipe option has no
247
effect if job control is enabled.
249
u. History expansion no longer expands the `$!' variable expansion.
251
v. Posix mode shells no longer exit if a variable assignment error occurs
252
with an assignment preceding a command that is not a special builtin.
254
w. Non-interactive mode shells exit if -u is enabled and an attempt is made
255
to use an unset variable with the % or # expansions, the `//', `^', or
256
`,' expansions, or the parameter length expansion.
258
x. Posix-mode shells use the argument passed to `.' as-is if a $PATH search
259
fails, effectively searching the current directory. Posix-2008 change.
261
2. New Features in Readline
263
a. The history library does not try to write the history filename in the
264
current directory if $HOME is unset. This closes a potential security
265
problem if the application does not specify a history filename.
267
b. New bindable variable `completion-display-width' to set the number of
268
columns used when displaying completions.
270
c. New bindable variable `completion-case-map' to cause case-insensitive
271
completion to treat `-' and `_' as identical.
273
d. There are new bindable vi-mode command names to avoid readline's case-
274
insensitive matching not allowing them to be bound separately.
276
e. New bindable variable `menu-complete-display-prefix' causes the menu
277
completion code to display the common prefix of the possible completions
278
before cycling through the list, instead of after.
280
-------------------------------------------------------------------------------
281
This is a terse description of the new features added to bash-4.1 since
282
the release of bash-4.0. As always, the manual page (doc/bash.1) is
283
the place to look for complete descriptions.
285
1. New Features in Bash
287
a. Here-documents within $(...) command substitutions may once more be
288
delimited by the closing right paren, instead of requiring a newline.
290
b. Bash's file status checks (executable, readable, etc.) now take file
291
system ACLs into account on file systems that support them.
293
c. Bash now passes environment variables with names that are not valid
294
shell variable names through into the environment passed to child
297
d. The `execute-unix-command' readline function now attempts to clear and
298
reuse the current line rather than move to a new one after the command
301
e. `printf -v' can now assign values to array indices.
303
f. New `complete -E' and `compopt -E' options that work on the "empty"
304
completion: completion attempted on an empty command line.
306
g. New complete/compgen/compopt -D option to define a `default' completion:
307
a completion to be invoked on command for which no completion has been
308
defined. If this function returns 124, programmable completion is
309
attempted again, allowing a user to dynamically build a set of completions
310
as completion is attempted by having the default completion function
311
install individual completion functions each time it is invoked.
313
h. When displaying associative arrays, subscripts are now quoted.
315
i. Changes to dabbrev-expand to make it more `emacs-like': no space appended
316
after matches, completions are not sorted, and most recent history entries
319
j. The [[ and (( commands are now subject to the setting of `set -e' and the
322
k. The source/. builtin now removes NUL bytes from the file before attempting
325
l. There is a new configuration option (in config-top.h) that forces bash to
326
forward all history entries to syslog.
328
m. A new variable $BASHOPTS to export shell options settable using `shopt' to
331
n. There is a new confgure option that forces the extglob option to be
334
o. New variable $BASH_XTRACEFD; when set to an integer bash will write xtrace
335
output to that file descriptor.
337
p. If the optional left-hand-side of a redirection is of the form {var}, the
338
shell assigns the file descriptor used to $var or uses $var as the file
339
descriptor to move or close, depending on the redirection operator.
341
q. The < and > operators to the [[ conditional command now do string
342
comparison according to the current locale if the compatibility level
345
r. Programmable completion now uses the completion for `b' instead of `a'
346
when completion is attempted on a line like: a $(b c.
348
s. Force extglob on temporarily when parsing the pattern argument to
349
the == and != operators to the [[ command, for compatibility.
351
t. Changed the behavior of interrupting the wait builtin when a SIGCHLD is
352
received and a trap on SIGCHLD is set to be Posix-mode only.
354
u. The read builtin has a new `-N nchars' option, which reads exactly NCHARS
355
characters, ignoring delimiters like newline.
357
v. The mapfile/readarray builtin no longer stores the commands it invokes via
358
callbacks in the history list.
360
w. There is a new `compat40' shopt option.
362
2. New Features in Readline
364
a. New bindable function: menu-complete-backward.
366
b. In the vi insertion keymap, C-n is now bound to menu-complete by default,
367
and C-p to menu-complete-backward.
369
c. When in vi command mode, repeatedly hitting ESC now does nothing, even
370
when ESC introduces a bound key sequence. This is closer to how
371
historical vi behaves.
373
d. New bindable function: skip-csi-sequence. Can be used as a default to
374
consume key sequences generated by keys like Home and End without having
377
e. New application-settable function: rl_filename_rewrite_hook. Can be used
378
to rewite or modify filenames read from the file system before they are
379
compared to the word to be completed.
381
f. New bindable variable: skip-completed-text, active when completing in the
382
middle of a word. If enabled, it means that characters in the completion
383
that match characters in the remainder of the word are "skipped" rather
384
than inserted into the line.
386
g. The pre-readline-6.0 version of menu completion is available as
387
"old-menu-complete" for users who do not like the readline-6.0 version.
389
h. New bindable variable: echo-control-characters. If enabled, and the
390
tty ECHOCTL bit is set, controls the echoing of characters corresponding
391
to keyboard-generated signals.
393
i. New bindable variable: enable-meta-key. Controls whether or not readline
394
sends the smm/rmm sequences if the terminal indicates it has a meta key
395
that enables eight-bit characters.
397
-------------------------------------------------------------------------------
398
This is a terse description of the new features added to bash-4.0 since
399
the release of bash-3.2. As always, the manual page (doc/bash.1) is
400
the place to look for complete descriptions.
402
1. New Features in Bash
404
a. When using substring expansion on the positional parameters, a starting
405
index of 0 now causes $0 to be prefixed to the list.
407
b. The `help' builtin now prints its columns with entries sorted vertically
408
rather than horizontally.
410
c. There is a new variable, $BASHPID, which always returns the process id of
413
d. There is a new `autocd' option that, when enabled, causes bash to attempt
414
to `cd' to a directory name that is supplied as the first word of a
417
e. There is a new `checkjobs' option that causes the shell to check for and
418
report any running or stopped jobs at exit.
420
f. The programmable completion code exports a new COMP_TYPE variable, set to
421
a character describing the type of completion being attempted.
423
g. The programmable completion code exports a new COMP_KEY variable, set to
424
the character that caused the completion to be invoked (e.g., TAB).
426
h. If creation of a child process fails due to insufficient resources, bash
427
will try again several times before reporting failure.
429
i. The programmable completion code now uses the same set of characters as
430
readline when breaking the command line into a list of words.
432
j. The block multiplier for the ulimit -c and -f options is now 512 when in
433
Posix mode, as Posix specifies.
435
k. Changed the behavior of the read builtin to save any partial input received
436
in the specified variable when the read builtin times out. This also
437
results in variables specified as arguments to read to be set to the empty
438
string when there is no input available. When the read builtin times out,
439
it returns an exit status greater than 128.
441
l. The shell now has the notion of a `compatibility level', controlled by
442
new variables settable by `shopt'. Setting this variable currently
443
restores the bash-3.1 behavior when processing quoted strings on the rhs
444
of the `=~' operator to the `[[' command.
446
m. The `ulimit' builtin now has new -b (socket buffer size) and -T (number
449
n. The -p option to `declare' now displays all variable values and attributes
450
(or function values and attributes if used with -f).
452
o. There is a new `compopt' builtin that allows completion functions to modify
453
completion options for existing completions or the completion currently
456
p. The `read' builtin has a new -i option which inserts text into the reply
457
buffer when using readline.
459
q. A new `-E' option to the complete builtin allows control of the default
460
behavior for completion on an empty line.
462
r. There is now limited support for completing command name words containing
465
s. Changed format of internal help documentation for all builtins to roughly
466
follow man page format.
468
t. The `help' builtin now has a new -d option, to display a short description,
469
and a -m option, to print help information in a man page-like format.
471
u. There is a new `mapfile' builtin to populate an array with lines from a
472
given file. The name `readarray' is a synonym.
474
v. If a command is not found, the shell attempts to execute a shell function
475
named `command_not_found_handle', supplying the command words as the
478
w. There is a new shell option: `globstar'. When enabled, the globbing code
479
treats `**' specially -- it matches all directories (and files within
480
them, when appropriate) recursively.
482
x. There is a new shell option: `dirspell'. When enabled, the filename
483
completion code performs spelling correction on directory names during
486
y. The `-t' option to the `read' builtin now supports fractional timeout
489
z. Brace expansion now allows zero-padding of expanded numeric values and
490
will add the proper number of zeroes to make sure all values contain the
491
same number of digits.
493
aa. There is a new bash-specific bindable readline function: `dabbrev-expand'.
494
It uses menu completion on a set of words taken from the history list.
496
bb. The command assigned to a key sequence with `bind -x' now sets two new
497
variables in the environment of the executed command: READLINE_LINE_BUFFER
498
and READLINE_POINT. The command can change the current readline line
499
and cursor position by modifying READLINE_LINE_BUFFER and READLINE_POINT,
502
cc. There is a new &>> redirection operator, which appends the standard output
503
and standard error to the named file.
505
dd. The parser now understands `|&' as a synonym for `2>&1 |', which redirects
506
the standard error for a command through a pipe.
508
ee. The new `;&' case statement action list terminator causes execution to
509
continue with the action associated with the next pattern in the
510
statement rather than terminating the command.
512
ff. The new `;;&' case statement action list terminator causes the shell to
513
test the next set of patterns after completing execution of the current
514
action, rather than terminating the command.
516
gg. The shell understands a new variable: PROMPT_DIRTRIM. When set to an
517
integer value greater than zero, prompt expansion of \w and \W will
518
retain only that number of trailing pathname components and replace
519
the intervening characters with `...'.
521
hh. There are new case-modifying word expansions: uppercase (^[^]) and
522
lowercase (,[,]). They can work on either the first character or
523
array element, or globally. They accept an optional shell pattern
524
that determines which characters to modify. There is an optionally-
525
configured feature to include capitalization operators.
527
ii. The shell provides associative array variables, with the appropriate
528
support to create, delete, assign values to, and expand them.
530
jj. The `declare' builtin now has new -l (convert value to lowercase upon
531
assignment) and -u (convert value to uppercase upon assignment) options.
532
There is an optionally-configurable -c option to capitalize a value at
535
kk. There is a new `coproc' reserved word that specifies a coprocess: an
536
asynchronous command run with two pipes connected to the creating shell.
537
Coprocs can be named. The input and output file descriptors and the
538
PID of the coprocess are available to the calling shell in variables
539
with coproc-specific names.
541
ll. A value of 0 for the -t option to `read' now returns success if there is
542
input available to be read from the specified file descriptor.
544
mm. CDPATH and GLOBIGNORE are ignored when the shell is running in privileged
547
nn. New bindable readline functions shell-forward-word and shell-backward-word,
548
which move forward and backward words delimited by shell metacharacters
549
and honor shell quoting.
551
oo. New bindable readline functions shell-backward-kill-word and shell-kill-word
552
which kill words backward and forward, but use the same word boundaries
553
as shell-forward-word and shell-backward-word.
555
2. New Features in Readline
557
a. A new variable, rl_sort_completion_matches; allows applications to inhibit
558
match list sorting (but beware: some things don't work right if
559
applications do this).
561
b. A new variable, rl_completion_invoking_key; allows applications to discover
562
the key that invoked rl_complete or rl_menu_complete.
564
c. The functions rl_block_sigint and rl_release_sigint are now public and
565
available to calling applications who want to protect critical sections
568
d. The functions rl_save_state and rl_restore_state are now public and
569
available to calling applications; documented rest of readline's state
572
e. A new user-settable variable, `history-size', allows setting the maximum
573
number of entries in the history list.
575
f. There is a new implementation of menu completion, with several improvements
576
over the old; the most notable improvement is a better `completions
579
g. The menu completion code now uses the rl_menu_completion_entry_function
580
variable, allowing applications to provide their own menu completion
583
h. There is support for replacing a prefix of a pathname with a `...' when
584
displaying possible completions. This is controllable by setting the
585
`completion-prefix-display-length' variable. Matches with a common prefix
586
longer than this value have the common prefix replaced with `...'.
588
i. There is a new `revert-all-at-newline' variable. If enabled, readline will
589
undo all outstanding changes to all history lines when `accept-line' is
592
j. If the kernel supports it, readline displays special characters
593
corresponding to a keyboard-generated signal when the signal is received.
595
-------------------------------------------------------------------------------
596
This is a terse description of the new features added to bash-3.2 since
597
the release of bash-3.1. As always, the manual page (doc/bash.1) is
598
the place to look for complete descriptions.
600
1. New Features in Bash
602
a. Changed the parameter pattern replacement functions to not anchor the
603
pattern at the beginning of the string if doing global replacement - that
604
combination doesn't make any sense.
606
b. When running in `word expansion only' mode (--wordexp option), inhibit
607
process substitution.
609
c. Loadable builtins now work on MacOS X 10.[34].
611
d. Shells running in posix mode no longer set $HOME, as POSIX requires.
613
e. The code that checks for binary files being executed as shell scripts now
614
checks only for NUL rather than any non-printing character.
616
f. Quoting the string argument to the [[ command's =~ operator now forces
617
string matching, as with the other pattern-matching operators.
619
2. New Features in Readline
621
a. Calling applications can now set the keyboard timeout to 0, allowing
624
b. The value of SYS_INPUTRC (configurable at compilation time) is now used as
625
the default last-ditch startup file.
627
c. The history file reading functions now allow windows-like \r\n line
630
-------------------------------------------------------------------------------
631
This is a terse description of the new features added to bash-3.1 since
632
the release of bash-3.0. As always, the manual page (doc/bash.1) is
633
the place to look for complete descriptions.
635
1. New Features in Bash
637
a. Bash now understands LC_TIME as a special variable so that time display
638
tracks the current locale.
640
b. BASH_ARGC, BASH_ARGV, BASH_SOURCE, and BASH_LINENO are no longer created
641
as `invisible' variables and may not be unset.
643
c. In POSIX mode, if `xpg_echo' option is enabled, the `echo' builtin doesn't
644
try to interpret any options at all, as POSIX requires.
646
d. The `bg' builtin now accepts multiple arguments, as POSIX seems to specify.
648
e. Fixed vi-mode word completion and glob expansion to perform tilde
651
f. The `**' mathematic exponentiation operator is now right-associative.
653
g. The `ulimit' builtin has new options: -i (max number of pending signals),
654
-q (max size of POSIX message queues), and -x (max number of file locks).
656
h. A bare `%' once again expands to the current job when used as a job
659
i. The `+=' assignment operator (append to the value of a string or array) is
660
now supported for assignment statements and arguments to builtin commands
661
that accept assignment statements.
663
j. BASH_COMMAND now preserves its value when a DEBUG trap is executed.
665
k. The `gnu_errfmt' option is enabled automatically if the shell is running
666
in an emacs terminal window.
668
l. New configuration option: --single-help-strings. Causes long help text
669
to be written as a single string; intended to ease translation.
671
m. The COMP_WORDBREAKS variable now causes the list of word break characters
672
to be emptied when the variable is unset.
674
n. An unquoted expansion of $* when $IFS is empty now causes the positional
675
parameters to be concatenated if the expansion doesn't undergo word
678
o. Bash now inherits $_ from the environment if it appears there at startup.
680
p. New shell option: nocasematch. If non-zero, shell pattern matching ignores
681
case when used by `case' and `[[' commands.
683
q. The `printf' builtin takes a new option: -v var. That causes the output
684
to be placed into var instead of on stdout.
686
r. By default, the shell no longer reports processes dying from SIGPIPE.
688
s. Bash now sets the extern variable `environ' to the export environment it
689
creates, so C library functions that call getenv() (and can't use the
690
shell-provided replacement) get current values of environment variables.
692
t. A new configuration option, `--enable-strict-posix-default', which will
693
build bash to be POSIX conforming by default.
695
u. If compiled for strict POSIX conformance, LINES and COLUMNS may now
696
override the true terminal size.
698
2. New Features in Readline
700
a. The key sequence sent by the keypad `delete' key is now automatically
701
bound to delete-char.
703
b. A negative argument to menu-complete now cycles backward through the
706
c. A new bindable readline variable: bind-tty-special-chars. If non-zero,
707
readline will bind the terminal special characters to their readline
708
equivalents when it's called (on by default).
710
d. New bindable command: vi-rubout. Saves deleted text for possible
711
reinsertion, as with any vi-mode `text modification' command; `X' is bound
712
to this in vi command mode.
714
e. A new external application-controllable variable that allows the LINES
715
and COLUMNS environment variables to set the window size regardless of
716
what the kernel returns: rl_prefer_env_winsize
718
-------------------------------------------------------------------------------
719
This is a terse description of the new features added to bash-3.0 since
720
the release of bash-2.05b. As always, the manual page (doc/bash.1) is
721
the place to look for complete descriptions.
723
1. New Features in Bash
725
a. ANSI string expansion now implements the \x{hexdigits} escape.
727
b. There is a new loadable `strftime' builtin.
729
c. New variable, COMP_WORDBREAKS, which controls the readline completer's
730
idea of word break characters.
732
d. The `type' builtin no longer reports on aliases unless alias expansion
733
will actually be performed.
735
e. HISTCONTROL is now a colon-separated list of values, which permits
736
more extensibility and backwards compatibility.
738
f. HISTCONTROL may now include the `erasedups' option, which causes all lines
739
matching a line being added to be removed from the history list.
741
g. `configure' has a new `--enable-multibyte' argument that permits multibyte
742
character support to be disabled even on systems that support it.
744
h. New variables to support the bash debugger: BASH_ARGC, BASH_ARGV,
745
BASH_SOURCE, BASH_LINENO, BASH_SUBSHELL, BASH_EXECUTION_STRING,
748
i. FUNCNAME has been changed to support the debugger: it's now an array
751
j. for, case, select, arithmetic commands now keep line number information
754
k. There is a new `RETURN' trap executed when a function or sourced script
755
returns (not inherited child processes; inherited by command substitution
756
if function tracing is enabled and the debugger is active).
758
l. New invocation option: --debugger. Enables debugging and turns on new
759
`extdebug' shell option.
761
m. New `functrace' and `errtrace' options to `set -o' cause DEBUG and ERR
762
traps, respectively, to be inherited by shell functions. Equivalent to
763
`set -T' and `set -E' respectively. The `functrace' option also controls
764
whether or not the DEBUG trap is inherited by sourced scripts.
766
n. The DEBUG trap is run before binding the variable and running the action
767
list in a `for' command, binding the selection variable and running the
768
query in a `select' command, and before attempting a match in a `case'
771
o. New `--enable-debugger' option to `configure' to compile in the debugger
774
p. `declare -F' now prints out extra line number and source file information
775
if the `extdebug' option is set.
777
q. If `extdebug' is enabled, a non-zero return value from a DEBUG trap causes
778
the next command to be skipped, and a return value of 2 while in a
779
function or sourced script forces a `return'.
781
r. New `caller' builtin to provide a call stack for the bash debugger.
783
s. The DEBUG trap is run just before the first command in a function body is
784
executed, for the debugger.
786
t. `for', `select', and `case' command heads are printed when `set -x' is
789
u. There is a new {x..y} brace expansion, which is shorthand for {x.x+1,
790
x+2,...,y}. x and y can be integers or single characters; the sequence
791
may ascend or descend; the increment is always 1.
793
v. New ksh93-like ${!array[@]} expansion, expands to all the keys (indices)
796
w. New `force_fignore' shopt option; if enabled, suffixes specified by
797
FIGNORE cause words to be ignored when performing word completion even
798
if they're the only possibilities.
800
x. New `gnu_errfmt' shopt option; if enabled, error messages follow the `gnu
801
style' (filename:lineno:message) format.
803
y. New `-o bashdefault' option to complete and compgen; if set, causes the
804
whole set of bash completions to be performed if the compspec doesn't
807
z. New `-o plusdirs' option to complete and compgen; if set, causes directory
808
name completion to be performed and the results added to the rest of the
809
possible completions.
811
aa. `kill' is available as a builtin even when the shell is built without
814
bb. New HISTTIMEFORMAT variable; value is a format string to pass to
815
strftime(3). If set and not null, the `history' builtin prints out
816
timestamp information according to the specified format when displaying
817
history entries. If set, bash tells the history library to write out
818
timestamp information when the history file is written.
820
cc. The [[ ... ]] command has a new binary `=~' operator that performs
821
extended regular expression (egrep-like) matching.
823
dd. `configure' has a new `--enable-cond-regexp' option (enabled by default)
824
to enable the =~ operator and regexp matching in [[ ... ]].
826
ee. Subexpressions matched by the =~ operator are placed in the new
827
BASH_REMATCH array variable.
829
ff. New `failglob' option that causes an expansion error when pathname
830
expansion fails to produce a match.
832
gg. New `set -o pipefail' option that causes a pipeline to return a failure
833
status if any of the processes in the pipeline fail, not just the last
836
hh. printf builtin understands two new escape sequences: \" and \?.
838
ii. `echo -e' understands two new escape sequences: \" and \?.
840
jj. The GNU `gettext' package and libintl have been integrated; the shell's
841
messages can be translated into different languages.
843
kk. The `\W' prompt expansion now abbreviates $HOME as `~', like `\w'.
845
ll. The error message printed when bash cannot open a shell script supplied
846
as argument 1 now includes the name of the shell, to better identify
847
the error as coming from bash.
849
mm. The parameter pattern removal and substitution expansions are now much
850
faster and more efficient when using multibyte characters.
852
nn. The `jobs', `kill', and `wait' builtins now accept job control notation
853
even if job control is not enabled.
855
oo. The historical behavior of `trap' that allows a missing `action' argument
856
to cause each specified signal's handling to be reset to its default is
857
now only supported when `trap' is given a single non-option argument.
859
2. New Features in Readline
861
a. History expansion has a new `a' modifier equivalent to the `g' modifier
862
for compatibility with the BSD csh.
864
b. History expansion has a new `G' modifier equivalent to the BSD csh `g'
865
modifier, which performs a substitution once per word.
867
c. All non-incremental search operations may now undo the operation of
868
replacing the current line with the history line.
870
d. The text inserted by an `a' command in vi mode can be reinserted with
873
e. New bindable variable, `show-all-if-unmodified'. If set, the readline
874
completer will list possible completions immediately if there is more
875
than one completion and partial completion cannot be performed.
877
f. There is a new application-callable `free_history_entry()' function.
879
g. History list entries now contain timestamp information; the history file
880
functions know how to read and write timestamp information associated
883
h. Four new key binding functions have been added:
885
rl_bind_key_if_unbound()
886
rl_bind_key_if_unbound_in_map()
887
rl_bind_keyseq_if_unbound()
888
rl_bind_keyseq_if_unbound_in_map()
890
i. New application variable, rl_completion_quote_character, set to any
891
quote character readline finds before it calls the application completion
894
j. New application variable, rl_completion_suppress_quote, settable by an
895
application completion function. If set to non-zero, readline does not
896
attempt to append a closing quote to a completed word.
898
k. New application variable, rl_completion_found_quote, set to a non-zero
899
value if readline determines that the word to be completed is quoted.
900
Set before readline calls any application completion function.
902
l. New function hook, rl_completion_word_break_hook, called when readline
903
needs to break a line into words when completion is attempted. Allows
904
the word break characters to vary based on position in the line.
906
m. New bindable command: unix-filename-rubout. Does the same thing as
907
unix-word-rubout, but adds `/' to the set of word delimiters.
909
n. When listing completions, directories have a `/' appended if the
910
`mark-directories' option has been enabled.
912
-------------------------------------------------------------------------------
913
This is a terse description of the new features added to bash-2.05b since
914
the release of bash-2.05a. As always, the manual page (doc/bash.1) is
915
the place to look for complete descriptions.
917
1. New Features in Bash
919
a. If set, TMOUT is the default timeout for the `read' builtin.
921
b. `type' has two new options: `-f' suppresses shell function lookup, and
922
`-P' forces a $PATH search.
924
c. New code to handle multibyte characters.
926
d. `select' was changed to be more ksh-compatible, in that the menu is
927
reprinted each time through the loop only if REPLY is set to NULL.
928
The previous behavior is available as a compile-time option.
930
e. `complete -d' and `complete -o dirnames' now force a slash to be
931
appended to names which are symlinks to directories.
933
f. There is now a bindable edit-and-execute-command readline command,
934
like the vi-mode `v' command, bound to C-xC-e in emacs mode.
936
g. Added support for ksh93-like [:word:] character class in pattern matching.
938
h. The $'...' quoting construct now expands \cX to Control-X.
940
i. A new \D{...} prompt expansion; passes the `...' to strftime and inserts
941
the result into the expanded prompt.
943
j. The shell now performs arithmetic in the largest integer size the
944
machine supports (intmax_t), instead of long.
946
k. If a numeric argument is supplied to one of the bash globbing completion
947
functions, a `*' is appended to the word before expansion is attempted.
949
l. The bash globbing completion functions now allow completions to be listed
950
with double tabs or if `show-all-if-ambiguous' is set.
952
m. New `-o nospace' option for `complete' and `compgen' builtins; suppresses
953
readline's appending a space to the completed word.
955
n. New `here-string' redirection operator: <<< word.
957
o. When displaying variables, function attributes and definitions are shown
958
separately, allowing them to be re-used as input (attempting to re-use
959
the old output would result in syntax errors).
961
p. There is a new configuration option `--enable-mem-scramble', controls
962
bash malloc behavior of writing garbage characters into memory at
963
allocation and free time.
965
q. The `complete' and `compgen' builtins now have a new `-s/-A service'
966
option to complete on names from /etc/services.
968
r. `read' has a new `-u fd' option to read from a specified file descriptor.
970
s. Fix the completion code so that expansion errors in a directory name
971
don't cause a longjmp back to the command loop.
973
t. Fixed word completion inside command substitution to work a little more
976
u. The `printf' %q format specifier now uses $'...' quoting to print the
977
argument if it contains non-printing characters.
979
v. The `declare' and `typeset' builtins have a new `-t' option. When applied
980
to functions, it causes the DEBUG trap to be inherited by the named
981
function. Currently has no effect on variables.
983
w. The DEBUG trap is now run *before* simple commands, ((...)) commands,
984
[[...]] conditional commands, and for ((...)) loops.
986
x. The expansion of $LINENO inside a shell function is only relative to the
987
function start if the shell is interactive -- if the shell is running a
988
script, $LINENO expands to the line number in the script. This is as
991
y. The bash debugger in examples/bashdb has been modified to work with the
992
new DEBUG trap semantics, the command set has been made more gdb-like,
993
and the changes to $LINENO make debugging functions work better. Code
996
z. New [n]<&word- and [n]>&word- redirections from ksh93 -- move fds (dup
999
aa. There is a new `-l' invocation option, equivalent to `--login'.
1001
bb. The `hash' builtin has a new `-l' option to list contents in a reusable
1002
format, and a `-d' option to remove a name from the hash table.
1004
cc. There is now support for placing the long help text into separate files
1005
installed into ${datadir}/bash. Not enabled by default; can be turned
1006
on with `--enable-separate-helpfiles' option to configure.
1008
dd. All builtins that take operands accept a `--' pseudo-option, except
1011
ee. The `echo' builtin now accepts \0xxx (zero to three octal digits following
1012
the `0') in addition to \xxx (one to three octal digits) for SUSv3/XPG6/
1013
POSIX.1-2001 compliance.
1016
2. New Features in Readline
1018
a. Support for key `subsequences': allows, e.g., ESC and ESC-a to both
1019
be bound to readline functions. Now the arrow keys may be used in vi
1022
b. When listing completions, and the number of lines displayed is more than
1023
the screen length, readline uses an internal pager to display the results.
1024
This is controlled by the `page-completions' variable (default on).
1026
c. New code to handle editing and displaying multibyte characters.
1028
d. The behavior introduced in bash-2.05a of deciding whether or not to
1029
append a slash to a completed name that is a symlink to a directory has
1030
been made optional, controlled by the `mark-symlinked-directories'
1031
variable (default is the 2.05a behavior).
1033
e. The `insert-comment' command now acts as a toggle if given a numeric
1034
argument: if the first characters on the line don't specify a
1035
comment, insert one; if they do, delete the comment text
1037
f. New application-settable completion variable:
1038
rl_completion_mark_symlink_dirs, allows an application's completion
1039
function to temporarily override the user's preference for appending
1040
slashes to names which are symlinks to directories.
1042
g. New function available to application completion functions:
1043
rl_completion_mode, to tell how the completion function was invoked
1044
and decide which argument to supply to rl_complete_internal (to list
1047
h. Readline now has an overwrite mode, toggled by the `overwrite-mode'
1048
bindable command, which could be bound to `Insert'.
1050
i. New application-settable completion variable:
1051
rl_completion_suppress_append, inhibits appending of
1052
rl_completion_append_character to completed words.
1054
j. New key bindings when reading an incremental search string: ^W yanks
1055
the currently-matched word out of the current line into the search
1056
string; ^Y yanks the rest of the current line into the search string,
1057
DEL or ^H deletes characters from the search string.
1059
-------------------------------------------------------------------------------
1060
This is a terse description of the new features added to bash-2.05a since
1061
the release of bash-2.05. As always, the manual page (doc/bash.1) is
1062
the place to look for complete descriptions.
1064
1. New Features in Bash
1066
a. Added support for DESTDIR installation root prefix, so you can do a
1067
`make install DESTDIR=bash-root' and do easier binary packaging.
1069
b. Added support for builtin printf "'" flag character as per latest POSIX
1072
c. Support for POSIX.2 printf(1) length specifiers `j', `t', and `z' (from
1075
d. New autoconf macro, RL_LIB_READLINE_VERSION, for use by other applications
1076
(bash doesn't use very much of what it returns).
1078
e. `set [-+]o nolog' is recognized as required by the latest POSIX drafts,
1081
f. New read-only `shopt' option: login_shell. Set to non-zero value if the
1082
shell is a login shell.
1084
g. New `\A' prompt string escape sequence; expands to time in 24 HH:MM format.
1086
h. New `-A group/-g' option to complete and compgen; does group name
1089
i. New `-t' option to `hash' to list hash values for each filename argument.
1091
j. New [-+]O invocation option to set and unset `shopt' options at startup.
1093
k. configure's `--with-installed-readline' option now takes an optional
1094
`=PATH' suffix to set the root of the tree where readline is installed
1097
l. The ksh-like `ERR' trap has been added. The `ERR' trap will be run
1098
whenever the shell would have exited if the -e option were enabled.
1099
It is not inherited by shell functions.
1101
m. `readonly', `export', and `declare' now print variables which have been
1102
given attributes but not set by assigning a value as just a command and
1103
a variable name (like `export foo') when listing, as the latest POSIX
1106
n. `bashbug' now requires that the subject be changed from the default.
1108
o. configure has a new `--enable-largefile' option, like other GNU utilities.
1110
p. `for' loops now allow empty word lists after `in', like the latest POSIX
1113
q. The builtin `ulimit' now takes two new non-numeric arguments: `hard',
1114
meaning the current hard limit, and `soft', meaning the current soft
1115
limit, in addition to `unlimited'
1117
r. `ulimit' now prints the option letter associated with a particular
1118
resource when printing more than one limit.
1120
s. `ulimit' prints `hard' or `soft' when a value is not `unlimited' but is
1121
one of RLIM_SAVED_MAX or RLIM_SAVED_CUR, respectively.
1123
t. The `printf' builtin now handles the %a and %A conversions if they're
1124
implemented by printf(3).
1126
u. The `printf' builtin now handles the %F conversion (just about like %f).
1128
v. The `printf' builtin now handles the %n conversion like printf(3). The
1129
corresponding argument is the name of a shell variable to which the
1132
2. New Features in Readline
1134
a. Added extern declaration for rl_get_termcap to readline.h, making it a
1135
public function (it was always there, just not in readline.h).
1137
b. New #defines in readline.h: RL_READLINE_VERSION, currently 0x0402,
1138
RL_VERSION_MAJOR, currently 4, and RL_VERSION_MINOR, currently 2.
1140
c. New readline variable: rl_readline_version, mirrors RL_READLINE_VERSION.
1142
d. New bindable boolean readline variable: match-hidden-files. Controls
1143
completion of files beginning with a `.' (on Unix). Enabled by default.
1145
e. The history expansion code now allows any character to terminate a
1146
`:first-' modifier, like csh.
1148
f. New bindable variable `history-preserve-point'. If set, the history
1149
code attempts to place the user at the same location on each history
1150
line retrived with previous-history or next-history.
1152
-------------------------------------------------------------------------------
1153
This is a terse description of the new features added to bash-2.05 since
1154
the release of bash-2.04. As always, the manual page (doc/bash.1) is
1155
the place to look for complete descriptions.
1157
1. New Features in Bash
1159
a. Added a new `--init-file' invocation argument as a synonym for `--rcfile',
1160
per the new GNU coding standards.
1162
b. The /dev/tcp and /dev/udp redirections now accept service names as well as
1165
c. `complete' and `compgen' now take a `-o value' option, which controls some
1166
of the aspects of that compspec. Valid values are:
1168
default - perform bash default completion if programmable
1169
completion produces no matches
1170
dirnames - perform directory name completion if programmable
1171
completion produces no matches
1172
filenames - tell readline that the compspec produces filenames,
1173
so it can do things like append slashes to
1174
directory names and suppress trailing spaces
1176
d. A new loadable builtin, realpath, which canonicalizes and expands symlinks
1177
in pathname arguments.
1179
e. When `set' is called without options, it prints function defintions in a
1180
way that allows them to be reused as input. This affects `declare' and
1181
`declare -p' as well. This only happens when the shell is not in POSIX
1182
mode, since POSIX.2 forbids this behavior.
1184
f. Bash-2.05 once again honors the current locale setting when processing
1185
ranges within pattern matching bracket expressions (e.g., [A-Z]).
1187
2. New Features in Readline
1189
a. The blink timeout for paren matching is now settable by applications,
1190
via the rl_set_paren_blink_timeout() function.
1192
b. _rl_executing_macro has been renamed to rl_executing_macro, which means
1193
it's now part of the public interface.
1195
c. Readline has a new variable, rl_readline_state, which is a bitmap that
1196
encapsulates the current state of the library; intended for use by
1197
callbacks and hook functions.
1199
d. New application-callable function rl_set_prompt(const char *prompt):
1200
expands its prompt string argument and sets rl_prompt to the result.
1202
e. New application-callable function rl_set_screen_size(int rows, int cols):
1203
public method for applications to set readline's idea of the screen
1206
f. New function, rl_get_screen_size (int *rows, int *columns), returns
1207
readline's idea of the screen dimensions.
1209
g. The timeout in rl_gather_tyi (readline keyboard input polling function)
1210
is now settable via a function (rl_set_keyboard_input_timeout()).
1212
h. Renamed the max_input_history variable to history_max_entries; the old
1213
variable is maintained for backwards compatibility.
1215
i. The list of characters that separate words for the history tokenizer is
1216
now settable with a variable: history_word_delimiters. The default
1219
-------------------------------------------------------------------------------
1220
This is a terse description of the new features added to bash-2.04 since
1221
the release of bash-2.03. As always, the manual page (doc/bash.1) is
1222
the place to look for complete descriptions.
1224
1. New Features in Bash
1226
a. The history builtin has a `-d offset' option to delete the history entry
1227
at position `offset'.
1229
b. The prompt expansion code has two new escape sequences: \j, the number of
1230
active jobs; and \l, the basename of the shell's tty device name.
1232
c. The `bind' builtin has a new `-x' option to bind key sequences to shell
1235
d. There is a new shell option, no_empty_command_completion, which, when
1236
enabled, disables command completion when TAB is typed on an empty line.
1238
e. The `help' builtin has a `-s' option to just print a builtin's usage
1241
f. There are several new arithmetic operators: id++, id-- (variable
1242
post-increment/decrement), ++id, --id (variable pre-increment/decrement),
1243
expr1 , expr2 (comma operator).
1245
g. There is a new ksh-93 style arithmetic for command:
1246
for ((expr1 ; expr2; expr3 )); do list; done
1248
h. The `read' builtin has a number of new options:
1249
-t timeout only wait timeout seconds for input
1250
-n nchars only read nchars from input instead of a full line
1251
-d delim read until delim rather than newline
1252
-s don't echo input chars as they are read
1254
i. The redirection code now handles several filenames specially:
1255
/dev/fd/N, /dev/stdin, /dev/stdout, and /dev/stderr, whether or
1256
not they are present in the file system.
1258
j. The redirection code now recognizes pathnames of the form
1259
/dev/tcp/host/port and /dev/udp/host/port, and tries to open a socket
1260
of the appropriate type to the specified port on the specified host.
1262
k. The ksh-93 ${!prefix*} expansion, which expands to the names of all
1263
shell variables with prefix PREFIX, has been implemented.
1265
l. There is a new dynamic variable, FUNCNAME, which expands to the name of
1266
a currently-executing function. Assignments to FUNCNAME have no effect.
1268
m. The GROUPS variable is no longer readonly; assignments to it are silently
1269
discarded. This means it can be unset.
1271
n. A new programmable completion facility, with two new builtin commands:
1272
complete and compgen.
1274
o. configure has a new option, `--enable-progcomp', to compile in the
1275
programmable completion features (enabled by default).
1277
p. `shopt' has a new option, `progcomp', to enable and disable programmable
1278
completion at runtime.
1280
q. Unsetting HOSTFILE now clears the list of hostnames used for completion.
1282
r. configure has a new option, `--enable-bash-malloc', replacing the old
1283
`--with-gnu-malloc' (which is still present for backwards compatibility).
1285
s. There is a new manual page describing rbash, the restricted shell.
1287
t. `bashbug' has new `--help' and `--version' options.
1289
u. `shopt' has a new `xpg_echo' option, which controls the behavior of
1290
`echo' with respect to backslash-escaped characters at runtime.
1292
v. If NON_INTERACTIVE_LOGIN_SHELLS is defined, all login shells read the
1293
startup files, even if they are not interactive.
1295
w. The LC_NUMERIC variable is now treated specially, and used to set the
1296
LC_NUMERIC locale category for number formatting, e.g., when `printf'
1297
displays floating-point numbers.
1299
2. New features in Readline
1301
a. Parentheses matching is now always compiled into readline, and enabled
1302
or disabled when the value of the `blink-matching-paren' variable is
1305
b. MS-DOS systems now use ~/_inputrc as the last-ditch inputrc filename.
1307
c. MS-DOS systems now use ~/_history as the default history file.
1309
d. history-search-{forward,backward} now leave the point at the end of the
1310
line when the string to search for is empty, like
1311
{reverse,forward}-search-history.
1313
e. history-search-{forward,backward} now leave the last history line found
1314
in the readline buffer if the second or subsequent search fails.
1316
f. New function for use by applications: rl_on_new_line_with_prompt, used
1317
when an application displays the prompt itself before calling readline().
1319
g. New variable for use by applications: rl_already_prompted. An application
1320
that displays the prompt itself before calling readline() must set this to
1323
h. A new variable, rl_gnu_readline_p, always 1. The intent is that an
1324
application can verify whether or not it is linked with the `real'
1325
readline library or some substitute.
1327
-------------------------------------------------------------------------------
1328
This is a terse description of the new features added to bash-2.03 since
1329
the release of bash-2.02. As always, the manual page (doc/bash.1) is
1330
the place to look for complete descriptions.
1332
1. New Features in Bash
1334
a. New `shopt' option, `restricted_shell', indicating whether or not the
1335
shell was started in restricted mode, for use in startup files.
1337
b. Filename generation is now performed on the words between ( and ) in
1338
array assignments (which it probably should have done all along).
1340
c. OLDPWD is now auto-exported, as POSIX.2 seems to require.
1342
d. ENV and BASH_ENV are read-only variables in a restricted shell.
1344
e. A change was made to the startup file code so that any shell begun with
1345
the `--login' option, even non-interactive shells, will source the login
1346
shell startup files.
1348
2. New Features in Readline
1350
a. Many changes to the signal handling:
1351
o Readline now catches SIGQUIT and cleans up the tty before returning;
1352
o A new variable, rl_catch_signals, is available to application writers
1353
to indicate to readline whether or not it should install its own
1354
signal handlers for SIGINT, SIGTERM, SIGQUIT, SIGALRM, SIGTSTP,
1355
SIGTTIN, and SIGTTOU;
1356
o A new variable, rl_catch_sigwinch, is available to application
1357
writers to indicate to readline whether or not it should install its
1358
own signal handler for SIGWINCH, which will chain to the calling
1359
applications's SIGWINCH handler, if one is installed;
1360
o There is a new function, rl_free_line_state, for application signal
1361
handlers to call to free up the state associated with the current
1362
line after receiving a signal;
1363
o There is a new function, rl_cleanup_after_signal, to clean up the
1364
display and terminal state after receiving a signal;
1365
o There is a new function, rl_reset_after_signal, to reinitialize the
1366
terminal and display state after an application signal handler
1367
returns and readline continues
1369
b. There is a new function, rl_resize_terminal, to reset readline's idea of
1370
the screen size after a SIGWINCH.
1372
c. New public functions: rl_save_prompt and rl_restore_prompt. These were
1373
previously private functions with a `_' prefix.
1375
d. New function hook: rl_pre_input_hook, called just before readline starts
1376
reading input, after initialization.
1378
e. New function hook: rl_display_matches_hook, called when readline would
1379
display the list of completion matches. The new function
1380
rl_display_match_list is what readline uses internally, and is available
1381
for use by application functions called via this hook.
1383
f. New bindable function, delete-char-or-list, like tcsh.
1385
g. A new variable, rl_erase_empty_line, which, if set by an application using
1386
readline, will cause readline to erase, prompt and all, lines on which the
1387
only thing typed was a newline.
1389
h. New bindable variable: `isearch-terminators'.
1391
i. New bindable function: `forward-backward-delete-char' (unbound by default).
1393
-------------------------------------------------------------------------------
1394
This is a terse description of the new features added to bash-2.02 since
1395
the release of bash-2.01.1. As always, the manual page (doc/bash.1) is
1396
the place to look for complete descriptions.
1398
1. New Features in Bash
1400
a. A new version of malloc, based on the older GNU malloc, that has many
1401
changes, is more page-based, is more conservative with memory usage,
1402
and does not `orphan' large blocks when they are freed.
1404
b. A new version of gmalloc, based on the old GLIBC malloc, with many
1405
changes and range checking included by default.
1407
c. A new implementation of fnmatch(3) that includes full POSIX.2 Basic
1408
Regular Expression matching, including character classes, collating
1409
symbols, equivalence classes, and support for case-insensitive pattern
1412
d. ksh-88 egrep-style extended pattern matching ([@+*?!](patlist)) has been
1413
implemented, controlled by a new `shopt' option, `extglob'.
1415
e. There is a new ksh-like `[[' compound command, which implements
1416
extended `test' functionality.
1418
f. There is a new `printf' builtin, implemented according to the POSIX.2
1421
g. There is a new feature for command substitution: $(< filename) now expands
1422
to the contents of `filename', with any trailing newlines removed
1423
(equivalent to $(cat filename)).
1425
h. There are new tilde prefixes which expand to directories from the
1428
i. There is a new `**' arithmetic operator to do exponentiation.
1430
j. There are new configuration options to control how bash is linked:
1431
`--enable-profiling', to allow bash to be profiled with gprof, and
1432
`--enable-static-link', to allow bash to be linked statically.
1434
k. There is a new configuration option, `--enable-cond-command', which
1435
controls whether or not the `[[' command is included. It is on by
1438
l. There is a new configuration option, `--enable-extended-glob', which
1439
controls whether or not the ksh extended globbing feature is included.
1440
It is enabled by default.
1442
m. There is a new configuration #define in config.h.top that, when enabled,
1443
will cause all login shells to source /etc/profile and one of the user-
1444
specific login shell startup files, whether or not the shell is
1447
n. There is a new invocation option, `--dump-po-strings', to dump
1448
a shell script's translatable strings ($"...") in GNU `po' format.
1450
o. There is a new `shopt' option, `nocaseglob', to enable case-insensitive
1451
pattern matching when globbing filenames and using the `case' construct.
1453
p. There is a new `shopt' option, `huponexit', which, when enabled, causes
1454
the shell to send SIGHUP to all jobs when an interactive login shell
1457
q. `bind' has a new `-u' option, which takes a readline function name as an
1458
argument and unbinds all key sequences bound to that function in a
1461
r. `disown' now has `-a' and `-r' options, to limit operation to all jobs
1462
and running jobs, respectively.
1464
s. The `shopt' `-p' option now causes output to be displayed in a reusable
1467
t. `test' has a new `-N' option, which returns true if the filename argument
1468
has been modified since it was last accessed.
1470
u. `umask' now has a `-p' option to print output in a reusable format.
1472
v. A new escape sequence, `\xNNN', has been added to the `echo -e' and $'...'
1473
translation code. It expands to the character whose ascii code is NNN
1476
w. The prompt string expansion code has a new `\r' escape sequence.
1478
x. The shell may now be cross-compiled for the CYGWIN32 environment on
1481
2. New Features in Readline
1483
a. There is now an option for `iterative' yank-last-arg handline, so a user
1484
can keep entering `M-.', yanking the last argument of successive history
1487
b. New variable, `print-completions-horizontally', which causes completion
1488
matches to be displayed across the screen (like `ls -x') rather than up
1489
and down the screen (like `ls').
1491
c. New variable, `completion-ignore-case', which causes filename completion
1492
and matching to be performed case-insensitively.
1494
d. There is a new bindable command, `magic-space', which causes history
1495
expansion to be performed on the current readline buffer and a space to
1496
be inserted into the result.
1498
e. There is a new bindable command, `menu-complete', which enables tcsh-like
1499
menu completion (successive executions of menu-complete insert a single
1500
completion match, cycling through the list of possible completions).
1502
f. There is a new bindable command, `paste-from-clipboard', for use on Win32
1503
systems, to insert the text from the Win32 clipboard into the editing
1506
g. The key sequence translation code now understands printf-style backslash
1507
escape sequences, including \NNN octal escapes. These escape sequences
1508
may be used in key sequence definitions or macro values.
1510
h. An `$include' inputrc file parser directive has been added.
1512
-------------------------------------------------------------------------------
1513
This is a terse description of the new features added to bash-2.01 since
1514
the release of bash-2.0. As always, the manual page (doc/bash.1) is the
1515
place to look for complete descriptions.
1517
1. New Features in Bash
1519
a. There is a new builtin array variable: GROUPS, the set of groups to which
1520
the user belongs. This is used by the test suite.
1522
2. New Features in Readline
1524
a. If a key sequence bound to `universal-argument' is read while reading a
1525
numeric argument started with `universal-argument', it terminates the
1526
argument but is otherwise ignored. This provides a way to insert multiple
1527
instances of a digit string, and is how GNU emacs does it.
1529
-------------------------------------------------------------------------------
1530
This is a terse description of the new features added to bash-2.0 since
1531
the release of bash-1.14.7. As always, the manual page (doc/bash.1) is
1532
the place to look for complete descriptions.
1534
1. New Features in Bash
1536
a. There is a new invocation option, -D, that dumps translatable strings
1539
b. The `long' invocation options must now be prefixed with `--'.
1541
c. New long invocation options: --dump-strings, --help, --verbose
1543
d. The `nolineediting' invocation option was renamed to `noediting'.
1545
e. The `nobraceexpansion' and `quiet' long invocation options were removed.
1547
f. The `--help' and `--version' long options now work as the GNU coding
1550
g. If invoked as `sh', bash now enters posix mode after reading the
1551
startup files, and reads and executes commands from the file named
1552
by $ENV if interactive (as POSIX.2 specifies). A login shell invoked
1553
as `sh' reads $ENV after /etc/profile and ~/.profile.
1555
h. There is a new reserved word, `time', for timing pipelines, builtin
1556
commands, and shell functions. It uses the value of the TIMEFORMAT
1557
variable as a format string describing how to print the timing
1560
i. The $'...' quoting syntax expands ANSI-C escapes in ... and leaves the
1561
result single-quoted.
1563
j. The $"..." quoting syntax performs locale-specific translation of ...
1564
and leaves the result double-quoted.
1566
k. LINENO now works correctly in functions.
1568
l. New variables: DIRSTACK, PIPESTATUS, BASH_VERSINFO, HOSTNAME, SHELLOPTS,
1569
MACHTYPE. The first three are array variables.
1571
m. The BASH_VERSION and BASH_VERSINFO variables now include the shell's
1572
`release status' (alpha[N], beta[N], release).
1574
n. Some variables have been removed: MAIL_WARNING, notify, history_control,
1575
command_oriented_history, glob_dot_filenames, allow_null_glob_expansion,
1576
nolinks, hostname_completion_file, noclobber, no_exit_on_failed_exec, and
1577
cdable_vars. Most of them are now implemented with the new `shopt'
1578
builtin; others were already implemented by `set'.
1580
o. Bash now uses some new variables: LC_ALL, LC_MESSAGES, LC_CTYPE,
1581
LC_COLLATE, LANG, GLOBIGNORE, HISTIGNORE.
1583
p. The shell now supports integer-indexed arrays of unlimited length,
1584
with a new compound assignment syntax and changes to the appropriate
1585
builtin commands (declare/typeset, read, readonly, etc.). The array
1586
index may be an arithmetic expression.
1588
q. ${!var}: indirect variable expansion, equivalent to eval \${$var}.
1590
r. ${paramter:offset[:length]}: variable substring extraction.
1592
s. ${parameter/pattern[/[/]string]}: variable pattern substitution.
1594
t. The $[...] arithmetic expansion syntax is no longer supported, in
1597
u. Aliases can now be expanded in shell scripts with a shell option
1598
(shopt expand_aliases).
1600
v. History and history expansion can now be used in scripts with
1601
set -o history and set -H.
1603
w. All builtins now return an exit status of 2 for incorrect usage.
1605
x. Interactive shells resend SIGHUP to all running or stopped children
1606
if (and only if) they exit due to a SIGHUP.
1608
y. New prompting expansions: \a, \e, \H, \T, \@, \v, \V.
1610
z. Variable expansion in prompt strings is now controllable via a shell
1611
option (shopt promptvars).
1613
aa. Bash now defaults to using command-oriented history.
1615
bb. The history file ($HISTFILE) is now truncated to $HISTFILESIZE after
1618
cc. The POSIX.2 conditional arithmetic evaluation syntax (expr ? expr : expr)
1619
has been implemented.
1621
dd. Each builtin now accepts `--' to signify the end of the options, except
1622
as documented (echo, etc.).
1624
ee. All builtins use -p to display values in a re-readable format where
1625
appropriate, except as documented (echo, type, etc.).
1627
ff. The `alias' builtin has a new -p option.
1629
gg. Changes to the `bind' builtin:
1630
o has new options: -psPSVr.
1631
o the `-d' option was renamed to `-p'
1632
o the `-v' option now dumps variables; the old `-v' is now `-P'
1634
hh. The `bye' synonym for `exit' was removed.
1636
ii. The -L and -P options to `cd' and `pwd' have been documented.
1638
jj. The `cd' builtin now does spelling correction on the directory name
1639
by default. This is settable with a shell option (shopt cdspell).
1641
kk. The `declare' builtin has new options: -a, -F, -p.
1643
ll. The `dirs' builtin has new options: -c, -p, -v.
1645
mm. The new `disown' builtin removes jobs from the shell's jobs table
1646
or inhibits the resending of SIGHUP when the shell receives a
1649
nn. The `echo' builtin has a new escape character: \e.
1651
oo. The `enable' builtin can now load new builtins dynamically from shared
1652
objects on systems with the dlopen/dlsym interface. There are a number
1653
of examples in the examples/loadables directory. There are also
1654
new options: -d, -f, -s, -p.
1656
pp. The `-all' option to `enable' was removed in favor of `-a'.
1658
qq. The `exec' builtin has new options: -l, -c, -a.
1660
rr. The `hash' builtin has a new option: -p.
1662
ss. The `history' builtin has new options: -c, -p, -s.
1664
tt. The `jobs' builtin has new options: -r, -s.
1666
uu. The `kill' builtin has new options: -n signum, -l signame.
1668
vv. The `pushd' and `popd' builtins have a new option: -n.
1670
ww. The `read' builtin has new options: -p prompt, -e, -a.
1672
xx. The `readonly' builtin has a new -a option, and the -n option was removed.
1674
yy. Changes to the `set' builtin:
1675
o new options: -B, -o keyword, -o onecmd, -o history
1676
o options removed: -l, -d, -o nohash
1677
o options changed: +o, -h, -o hashall
1678
o now displays variables in a format that can be re-read as input
1680
zz. The new `shopt' builtin controls shell optional behavior previously
1681
done by setting and unsetting certain shell variables.
1683
aaa. The `test' builtin has new operators: -o option, s1 == s2, s1 < s2,
1684
and s1 > s2, where s1 and s2 are strings.
1686
bbb. There is a new trap, DEBUG, executed after every simple command.
1688
ccc. The `trap' builtin has a new -p option.
1690
ddd. The `ulimit' builtin has a new -l option on 4.4BSD-based systems.
1692
eee. The PS1, PS2, PATH, and IFS variables may now be unset.
1694
fff. The restricted shell mode has been expanded and is now documented.
1696
ggg. Security improvements:
1697
o functions are not imported from the environment if running setuid
1699
o no startup files are sourced if running setuid or with -p
1701
hhh. The documentation has been overhauled: the texinfo manual was
1702
expanded, and HTML versions of the man page and texinfo manual
1705
iii. Changes to Posix mode:
1706
o Command lookup now finds special builtins before shell functions.
1707
o Failure of a special builtin causes a non-interactive shell to
1708
exit. Failures are defined in the POSIX.2 specification.
1709
o If the `cd' builtin finds a directory to change to using $CDPATH,
1710
the value assigned to PWD when `cd' completes does not contain
1712
o A non-interactive shell exits if a variable assignment error
1713
occurs when no command name follows the assignment statements.
1714
o A non-interactive shell exits if the interation variable in a
1715
`for' statement or the selection variable in a `select' statement
1716
is read-only or another variable assignment error occurs.
1717
o The `<>' redirection operator now opens a file for both stdin and
1718
stdout by default, not just when in posix mode.
1719
o Assignment statements preceding special builtins now persist in
1720
the shell's environment when the builtin completes.
1722
Posix mode is now completely POSIX.2-compliant (modulo bugs). When
1723
invoked as sh, bash should be completely POSIX.2-compliant.
1725
jjj. The default value of PS1 is now "\s-\v\$ ".
1727
kkk. The ksh-like ((...)) arithmetic command syntax has been implemented.
1728
This is exactly equivalent to `let "..."'.
1730
lll. Integer constants have been extended to base 64.
1732
mmm. The `ulimit' builtin now sets both hard and soft limits and reports the
1733
soft limit by default.
1735
2. New Features in Readline
1737
a. New variables: enable-keypad, input-meta (new name for meta-flag),
1738
mark-directories, visible-stats (now documented), disable-completion,
1741
b. New bindable commands: kill-region, copy-region-as-kill,
1742
copy-backward-word, copy-forward-word, set-mark, exchange-point-and-mark,
1743
character-search, character-search-backward, insert-comment,
1744
glob-expand-word, glob-list-expansions, dump-variables, dump-macros.
1746
c. New emacs keybindings: delete-horizontal-space (M-\),
1747
insert-completions (M-*), possible-completions (M-=).
1749
d. The history-search-backward and history-search-forward commands were
1750
modified to be the same as previous-line and next-line if point is at
1751
the start of the line.
1753
e. More file types are available for the visible-stats mode.
1755
3. Changes of interest in the Bash implementation
1757
a. There is a new autoconf-based configuration mechanism.
1759
b. More things have been moved from Posix mode to standard shell behavior.
1761
c. The trace output (set -x) now inserts quotes where necessary so it can
1764
d. There is a compile-time option for a system-wide interactive shell
1765
startup file (disabled by default).
1767
e. The YACC grammar is smaller and tighter, and all 66 shift-reduce
1768
conflicts are gone. Several parsing bugs have been fixed.
1770
f. Builtin option parsing has been regularized (using internal_getopt()),
1771
with the exception of `echo', `type', and `set'.
1773
g. Builtins now return standard usage messages constructed from the
1774
`short doc' used by the help builtin.
1776
h. Completion now quotes using backslashes by default, but honors
1777
user-supplied quotes.
1779
i. The GNU libc malloc is available as a configure-time option.
1781
j. There are more internationalization features; bash uses gettext if
1782
it is available. The $"..." translation syntax uses the current
1785
k. There is better reporting of job termination when the shell is not
1788
l. The shell is somewhat more efficient: it uses a little less memory and
1789
makes fewer system calls.
1791
4. Changes of interest in the Readline implementation
1793
a. There is now support for readline `callback' functions.
1795
b. There is now support for user-supplied input, redisplay, and terminal
1796
preparation functions.
1798
c. Most of the shell-specific code in readline has been generalized or
1801
d. Most of the annoying redisplay bugs have been fixed, notably the problems
1802
with incremental search and excessive redrawing when special characters
1803
appear in the prompt string.
1805
e. There are new library functions and variables available to application
1806
writers, most having to do with completion and quoting.
1808
f. The NEWLINE character (^J) is now treated as a search terminator by the
1809
incremental search functions.
1810
-------------------------------------------------------------------------------
1812
Copying and distribution of this file, with or without modification,
1813
are permitted in any medium without royalty provided the copyright
1814
notice and this notice are preserved. This file is offered as-is,
1815
without any warranty.
added
removed
NEWS
