fix for heuristic to detect case statements when parsing $() command substitutions to find history expansion; fix for history not being saved if a SIGHUP arrives during $PROMPT_COMMAND execution; workaround for Cygwin bug that results in bash incorrectly calculating the system pipe size

doc/bashref.info

@@ -2,9 +2,9 @@ This is bashref.info, produced by makeinfo version 7.2 from
 bashref.texi.
 
 This text is a brief description of the features that are present in the
-Bash shell (version 5.3, 27 February 2026).
+Bash shell (version 5.3, 3 March 2026).
 
-   This is Edition 5.3, last updated 27 February 2026, of ‘The GNU Bash
+   This is Edition 5.3, last updated 3 March 2026, of ‘The GNU Bash
 Reference Manual’, for ‘Bash’, Version 5.3.
 
    Copyright © 1988-2026 Free Software Foundation, Inc.
@@ -27,10 +27,10 @@ Bash Features
 *************
 
 This text is a brief description of the features that are present in the
-Bash shell (version 5.3, 27 February 2026).  The Bash home page is
+Bash shell (version 5.3, 3 March 2026).  The Bash home page is
 <http://www.gnu.org/software/bash/>.
 
-   This is Edition 5.3, last updated 27 February 2026, of ‘The GNU Bash
+   This is Edition 5.3, last updated 3 March 2026, of ‘The GNU Bash
 Reference Manual’, for ‘Bash’, Version 5.3.
 
    Bash contains features that appear in other popular shells, and some
@@ -1897,16 +1897,17 @@ introduce indirection.
    In each of the cases below, WORD is subject to tilde expansion,
 parameter expansion, command substitution, and arithmetic expansion.
 
-   When not performing substring expansion, using the forms described
-below (e.g., ‘:−’), Bash tests for a parameter that is unset or null.
-Omitting the colon results in a test only for a parameter that is unset.
-Put another way, if the colon is included, the operator tests for both
-PARAMETER's existence and that its value is not null; if the colon is
-omitted, the operator tests only for existence.
+   When performing the first four expansions documented below (‘:-’,
+‘:=’, ‘:?’, and ‘:+’), including the colon, Bash tests for a parameter
+that is unset or null.  Omitting the colon results in a test only for a
+parameter that is unset.  Put another way, if the colon is included, the
+operator tests for both PARAMETER's existence and that its value is not
+null; if the colon is omitted, the operator tests only for existence.
 
 ‘${PARAMETER:−WORD}’
-     If PARAMETER is unset or null, the expansion of WORD is
-     substituted.  Otherwise, the value of PARAMETER is substituted.
+     If PARAMETER is unset or null, or unset if the colon is not
+     present, the expansion of WORD is substituted.  Otherwise, the
+     value of PARAMETER is substituted.
 
           $ v=123
           $ echo ${v-unset}
@@ -1923,10 +1924,11 @@ omitted, the operator tests only for existence.
           unset-or-null
 
 ‘${PARAMETER:=WORD}’
-     If PARAMETER is unset or null, the expansion of WORD is assigned to
-     PARAMETER, and the result of the expansion is the final value of
-     PARAMETER.  Positional parameters and special parameters may not be
-     assigned in this way.
+     If PARAMETER is unset or null, or unset if the colon is not
+     present, the expansion of WORD is assigned to PARAMETER, and the
+     result of the expansion is the final value of PARAMETER.
+     Positional parameters and special parameters may not be assigned in
+     this way.
 
           $ unset var
           $ : ${var=DEFAULT}
@@ -1946,12 +1948,13 @@ omitted, the operator tests only for existence.
           DEFAULT
 
 ‘${PARAMETER:?WORD}’
-     If PARAMETER is null or unset, the shell writes the expansion of
-     WORD (or a message to that effect if WORD is not present) to the
-     standard error and, if it is not interactive, exits with a non-zero
-     status.  An interactive shell does not exit, but does not execute
-     the command associated with the expansion.  Otherwise, the value of
-     PARAMETER is substituted.
+     If PARAMETER is unset or null, or unset if the colon is not
+     present, the shell writes the expansion of WORD (or a message to
+     that effect if WORD is not present) to the standard error and, if
+     it is not interactive, exits with a non-zero status.  An
+     interactive shell does not exit, but does not execute the command
+     associated with the expansion.  Otherwise, the value of PARAMETER
+     is substituted.
 
           $ var=
           $ : ${var:?var is unset or null}
@@ -1968,9 +1971,9 @@ omitted, the operator tests only for existence.
           123
 
 ‘${PARAMETER:+WORD}’
-     If PARAMETER is null or unset, nothing is substituted, otherwise
-     the expansion of WORD is substituted.  The value of PARAMETER is
-     not used.
+     If PARAMETER is unset or null, or unset if the colon is not
+     present, nothing is substituted, otherwise the expansion of WORD is
+     substituted.  The value of PARAMETER is not used.
 
           $ var=123
           $ echo ${var:+var is set and not null}
@@ -7164,7 +7167,7 @@ shell variables may also be referenced by name without using the
 parameter expansion syntax.  This means you can use X, where X is a
 shell variable name, in an arithmetic expression, and the shell will
 evaluate its value as an expression and use the result.  A shell
-variable that is null or unset evaluates to 0 when referenced by name in
+variable that is unset or null evaluates to 0 when referenced by name in
 an expression.
 
    The value of a variable is evaluated as an arithmetic expression when
@@ -13736,138 +13739,138 @@ D.5 Concept Index
 
 
 Tag Table:
-Node: Top904
-Node: Introduction2848
-Node: What is Bash?3064
-Node: What is a shell?4200
-Node: Definitions6813
-Node: Basic Shell Features10143
-Node: Shell Syntax11370
-Node: Shell Operation12400
-Node: Quoting13694
-Node: Escape Character15035
-Node: Single Quotes15573
-Node: Double Quotes15925
-Node: ANSI-C Quoting17273
-Node: Locale Translation18670
-Node: Creating Internationalized Scripts20076
-Node: Comments24277
-Node: Shell Commands25047
-Node: Reserved Words25989
-Node: Simple Commands27135
-Node: Pipelines27800
-Node: Lists31059
-Node: Compound Commands33011
-Node: Looping Constructs34023
-Node: Conditional Constructs36575
-Node: Command Grouping51715
-Node: Coprocesses53210
-Node: GNU Parallel55899
-Node: Shell Functions56820
-Node: Shell Parameters65271
-Node: Positional Parameters70175
-Node: Special Parameters71268
-Node: Shell Expansions74732
-Node: Brace Expansion76924
-Node: Tilde Expansion80263
-Node: Shell Parameter Expansion83221
-Node: Command Substitution103871
-Node: Arithmetic Expansion107725
-Node: Process Substitution108904
-Node: Word Splitting110015
-Node: Filename Expansion112462
-Node: Pattern Matching115689
-Node: Quote Removal121458
-Node: Redirections121765
-Node: Executing Commands132024
-Node: Simple Command Expansion132694
-Node: Command Search and Execution134805
-Node: Command Execution Environment137252
-Node: Environment140781
-Node: Exit Status142687
-Node: Signals144749
-Node: Shell Scripts149700
-Node: Shell Builtin Commands153001
-Node: Bourne Shell Builtins155345
-Node: Bash Builtins182067
-Node: Modifying Shell Behavior219806
-Node: The Set Builtin220151
-Node: The Shopt Builtin232148
-Node: Special Builtins249204
-Node: Shell Variables250196
-Node: Bourne Shell Variables250633
-Node: Bash Variables253144
-Node: Bash Features292431
-Node: Invoking Bash293448
-Node: Bash Startup Files300035
-Node: Interactive Shells305280
-Node: What is an Interactive Shell?305691
-Node: Is this Shell Interactive?306356
-Node: Interactive Shell Behavior307183
-Node: Bash Conditional Expressions310947
-Node: Shell Arithmetic316367
-Node: Aliases319697
-Node: Arrays322834
-Node: The Directory Stack330540
-Node: Directory Stack Builtins331340
-Node: Controlling the Prompt335788
-Node: The Restricted Shell338675
-Node: Bash POSIX Mode341771
-Node: Shell Compatibility Mode361590
-Node: Job Control370600
-Node: Job Control Basics371060
-Node: Job Control Builtins377431
-Node: Job Control Variables384222
-Node: Command Line Editing385456
-Node: Introduction and Notation387162
-Node: Readline Interaction389517
-Node: Readline Bare Essentials390708
-Node: Readline Movement Commands392519
-Node: Readline Killing Commands393518
-Node: Readline Arguments395544
-Node: Searching396637
-Node: Readline Init File398883
-Node: Readline Init File Syntax400189
-Node: Conditional Init Constructs427143
-Node: Sample Init File431531
-Node: Bindable Readline Commands434654
-Node: Commands For Moving436195
-Node: Commands For History438662
-Node: Commands For Text444056
-Node: Commands For Killing448184
-Node: Numeric Arguments450975
-Node: Commands For Completion452130
-Node: Keyboard Macros457829
-Node: Miscellaneous Commands458533
-Node: Readline vi Mode466079
-Node: Programmable Completion467059
-Node: Programmable Completion Builtins476798
-Node: A Programmable Completion Example488538
-Node: Using History Interactively493886
-Node: Bash History Facilities494570
-Node: Bash History Builtins498308
-Node: History Interaction505906
-Node: Event Designators510859
-Node: Word Designators512440
-Node: Modifiers514835
-Node: Installing Bash516775
-Node: Basic Installation517894
-Node: Compilers and Options521773
-Node: Compiling For Multiple Architectures522526
-Node: Installation Names524282
-Node: Specifying the System Type526519
-Node: Sharing Defaults527268
-Node: Operation Controls527985
-Node: Optional Features529007
-Node: Reporting Bugs541733
-Node: Major Differences From The Bourne Shell543093
-Node: GNU Free Documentation License564523
-Node: Indexes589703
-Node: Builtin Index590157
-Node: Reserved Word Index597258
-Node: Variable Index599706
-Node: Function Index617122
-Node: Concept Index631258
+Node: Top896
+Node: Introduction2832
+Node: What is Bash?3048
+Node: What is a shell?4184
+Node: Definitions6797
+Node: Basic Shell Features10127
+Node: Shell Syntax11354
+Node: Shell Operation12384
+Node: Quoting13678
+Node: Escape Character15019
+Node: Single Quotes15557
+Node: Double Quotes15909
+Node: ANSI-C Quoting17257
+Node: Locale Translation18654
+Node: Creating Internationalized Scripts20060
+Node: Comments24261
+Node: Shell Commands25031
+Node: Reserved Words25973
+Node: Simple Commands27119
+Node: Pipelines27784
+Node: Lists31043
+Node: Compound Commands32995
+Node: Looping Constructs34007
+Node: Conditional Constructs36559
+Node: Command Grouping51699
+Node: Coprocesses53194
+Node: GNU Parallel55883
+Node: Shell Functions56804
+Node: Shell Parameters65255
+Node: Positional Parameters70159
+Node: Special Parameters71252
+Node: Shell Expansions74716
+Node: Brace Expansion76908
+Node: Tilde Expansion80247
+Node: Shell Parameter Expansion83205
+Node: Command Substitution104056
+Node: Arithmetic Expansion107910
+Node: Process Substitution109089
+Node: Word Splitting110200
+Node: Filename Expansion112647
+Node: Pattern Matching115874
+Node: Quote Removal121643
+Node: Redirections121950
+Node: Executing Commands132209
+Node: Simple Command Expansion132879
+Node: Command Search and Execution134990
+Node: Command Execution Environment137437
+Node: Environment140966
+Node: Exit Status142872
+Node: Signals144934
+Node: Shell Scripts149885
+Node: Shell Builtin Commands153186
+Node: Bourne Shell Builtins155530
+Node: Bash Builtins182252
+Node: Modifying Shell Behavior219991
+Node: The Set Builtin220336
+Node: The Shopt Builtin232333
+Node: Special Builtins249389
+Node: Shell Variables250381
+Node: Bourne Shell Variables250818
+Node: Bash Variables253329
+Node: Bash Features292616
+Node: Invoking Bash293633
+Node: Bash Startup Files300220
+Node: Interactive Shells305465
+Node: What is an Interactive Shell?305876
+Node: Is this Shell Interactive?306541
+Node: Interactive Shell Behavior307368
+Node: Bash Conditional Expressions311132
+Node: Shell Arithmetic316552
+Node: Aliases319882
+Node: Arrays323019
+Node: The Directory Stack330725
+Node: Directory Stack Builtins331525
+Node: Controlling the Prompt335973
+Node: The Restricted Shell338860
+Node: Bash POSIX Mode341956
+Node: Shell Compatibility Mode361775
+Node: Job Control370785
+Node: Job Control Basics371245
+Node: Job Control Builtins377616
+Node: Job Control Variables384407
+Node: Command Line Editing385641
+Node: Introduction and Notation387347
+Node: Readline Interaction389702
+Node: Readline Bare Essentials390893
+Node: Readline Movement Commands392704
+Node: Readline Killing Commands393703
+Node: Readline Arguments395729
+Node: Searching396822
+Node: Readline Init File399068
+Node: Readline Init File Syntax400374
+Node: Conditional Init Constructs427328
+Node: Sample Init File431716
+Node: Bindable Readline Commands434839
+Node: Commands For Moving436380
+Node: Commands For History438847
+Node: Commands For Text444241
+Node: Commands For Killing448369
+Node: Numeric Arguments451160
+Node: Commands For Completion452315
+Node: Keyboard Macros458014
+Node: Miscellaneous Commands458718
+Node: Readline vi Mode466264
+Node: Programmable Completion467244
+Node: Programmable Completion Builtins476983
+Node: A Programmable Completion Example488723
+Node: Using History Interactively494071
+Node: Bash History Facilities494755
+Node: Bash History Builtins498493
+Node: History Interaction506091
+Node: Event Designators511044
+Node: Word Designators512625
+Node: Modifiers515020
+Node: Installing Bash516960
+Node: Basic Installation518079
+Node: Compilers and Options521958
+Node: Compiling For Multiple Architectures522711
+Node: Installation Names524467
+Node: Specifying the System Type526704
+Node: Sharing Defaults527453
+Node: Operation Controls528170
+Node: Optional Features529192
+Node: Reporting Bugs541918
+Node: Major Differences From The Bourne Shell543278
+Node: GNU Free Documentation License564708
+Node: Indexes589888
+Node: Builtin Index590342
+Node: Reserved Word Index597443
+Node: Variable Index599891
+Node: Function Index617307
+Node: Concept Index631443
 
 End Tag Table