[PATCH 7/9] Improve bash.1 man page/bashref.texi alignment.

[G. Branden Robinson]

Break lines in the same places for ease of diffing and maintenance.

Parallelize/copy material to align the documents more closely.

Favor man(7) font selection/alternation macros over roff(7) font
selection escape sequences.

Protect more literals from hyphenation.

Quote the `+=` operator in the man page as it is in Texinfo.

Write "key-value pairs" with a plain hyphen, not a minus sign.
---
 doc/bash.1       | 427 +++++++++++++++++++++++++------------
 doc/bashref.texi | 538 +++++++++++++++++++++++++++++++++--------------
 2 files changed, 678 insertions(+), 287 deletions(-)

diff --git a/doc/bash.1 b/doc/bash.1
index e7a3ae9e..5811e2ce 100644
--- a/doc/bash.1
+++ b/doc/bash.1
@@ -286,42 +286,58 @@ .SH OPTIONS
 .B bash
 on the standard output and exit successfully.
 .SH ARGUMENTS
-If arguments remain after option processing, and neither the
+If arguments remain after option processing,
+and neither the
 .B \-c
 nor the
 .B \-s
-option has been supplied, the first argument is assumed to
-be the name of a file containing shell commands (a \fIshell script\fP).
-If
+option has been supplied,
+the first argument is assumed to be the name of a file
+containing shell commands
+(a
+.IR "shell script" ).
+When
 .B bash
 is invoked in this fashion,
 .B $0
-is set to the name of the file, and the positional parameters
-are set to the remaining arguments.
+is set to the name of the file,
+and the positional parameters are set to the remaining arguments.
 .B Bash
 reads and executes commands from this file, then exits.
-\fBBash\fP's exit status is the exit status of the last command
-executed in the script.
-If no commands are executed, the exit status is 0.
-Bash first attempts to open the file in the current directory, and,
-if no file is found, then searches the directories in
+.BR Bash 's
+exit status is the exit status of the last command executed
+in the script.
+If no commands are executed,
+the exit status is 0.
+.B Bash
+first attempts to open the file in the current directory,
+and,
+if no file is found,
+then searches the directories in
 .SM
 .B PATH
 for the script.
 .SH INVOCATION
-A \fIlogin shell\fP is one whose first character of argument zero is a
+A
+.I "login shell"
+is one whose first character of argument zero is a
 .BR \- ,
 or one started with the
 .B \-\-login
 option.
 .PP
-An \fIinteractive\fP shell is one started without non-option arguments
-(unless \fB\-s\fP is specified)
-and without the
+An
+.I interactive
+shell is one started without non-option arguments
+(unless
+.B \-s
+is specified),
+without specifying the
 .B \-c
 option,
-whose standard input and standard error are
-both connected to terminals (as determined by
+and whose standard input and standard error
+are both connected to terminals
+(as determined by
 .IR isatty (3)),
 or one started with the
 .B \-i
@@ -420,33 +436,40 @@ .SH INVOCATION
 while conforming to the
 .SM POSIX
 standard as well.
-When invoked as an interactive login shell, or a non-interactive
-shell with the \fB\-\-login\fP option, it first attempts to
-read and execute commands from
+.IP
+When invoked as an interactive login shell,
+or a non-interactive shell with the
+.B \%\-\-login
+option,
+it first attempts to read and execute commands from
 .FN /etc/profile
 and
 .FN \*~/.profile ,
 in that order.
 The
-.B \-\-noprofile
+.B \%\-\-noprofile
 option inhibits this behavior.
+.IP
 When invoked as an interactive shell with the name
 .BR sh ,
 .B bash
 looks for the variable
 .SM
 .BR ENV ,
-expands its value if it is defined, and uses the
-expanded value as the name of a file to read and execute.
+expands its value if it is defined,
+and uses the expanded value as the name of a file to read and execute.
 Since a shell invoked as
 .B sh
 does not attempt to read and execute commands from any other startup
-files, the
+files,
+the
 .B \-\-rcfile
 option has no effect.
+.IP
 A non-interactive shell invoked with the name
 .B sh
 does not attempt to read any other startup files.
+.IP
 When invoked as
 .BR sh ,
 .B bash
@@ -1204,7 +1227,8 @@ .SH QUOTING
 (see
 .SM
 .B "HISTORY EXPANSION"
-below), the
+below),
+the
 \fIhistory expansion\fP character, usually \fB!\fP, must be quoted
 to prevent history expansion.
 .PP
@@ -1268,8 +1292,8 @@ .SH QUOTING
 .B *
 and
 .B @
-have special meaning when in double
-quotes (see
+have special meaning when in double quotes
+(see
 .SM
 .B PARAMETERS
 below).
@@ -1440,27 +1464,44 @@ .SH PARAMETERS
 assignment statement properties.
 .PP
 In the context where an assignment statement is assigning a value
-to a shell variable or array index,
-the += operator appends to or adds to
-the variable's previous value.
-This includes arguments to \fIdeclaration\fP commands such as
-\fBdeclare\fP that accept assignment statements.
-When += is applied to a variable
-for which the \fBinteger\fP attribute has been set,
-the variable's current value and \fIvalue\fP are each evaluated as
-arithmetic expressions,
-and the sum of the results is assigned as the variable's value.
-The current value is usually an integer constant, but may be an expression.
-When += is applied to an array variable using compound assignment
+to a shell variable or array index
 (see
 .B Arrays
 below), the
-variable's value is not unset (as it is when using =), and new
-values are appended to the array beginning at one greater than the array's
-maximum index (for indexed arrays) or added as additional key\-value pairs
-in an associative array.
-When applied to a string-valued variable, \fIvalue\fP is expanded and
-appended to the variable's value.
+the
+.Q +=
+operator appends to or adds to the variable's previous value.
+This includes arguments to declaration commands such as
+.B \%declare
+that accept assignment statements.
+When
+.Q +=
+is applied to a variable
+for which the
+.B \%integer
+attribute has been set,
+the variable's current value and
+.I value
+are each evaluated as arithmetic expressions,
+and the sum of the results is assigned as the variable's value.
+The current value is usually an integer constant,
+but may be an expression.
+When
+.Q +=
+is applied to an array variable using compound assignment
+(see
+.B Arrays
+below),
+the variable's value is not unset
+(as it is when using
+.Q = ),
+and new values are appended to the array
+beginning at one greater than the array's maximum index
+(for indexed arrays),
+or added as additional key-value pairs in an associative array.
+When applied to a string-valued variable,
+.I value
+is expanded and appended to the variable's value.
 .PP
 A variable can be assigned the \fInameref\fP attribute using the
 \fB\-n\fP option to the \fBdeclare\fP or \fBlocal\fP builtin commands
@@ -2198,7 +2239,8 @@ .SS "Shell Variables"
 command.
 .TP
 .B RANDOM
-Each time this parameter is referenced, it expands to a random integer
+Each time this parameter is referenced,
+it expands to a random integer
 between 0 and 32767.
 Assigning a value to
 .SM
@@ -2213,7 +2255,9 @@ .SS "Shell Variables"
 subsequently reset.
 .TP
 .B READLINE_ARGUMENT
-Any numeric argument given to a \fBreadline\fP command that was defined using
+Any numeric argument given to a
+.B \%readline
+command that was defined using
 .Q "bind \-x"
 (see
 .SM
@@ -2241,7 +2285,8 @@ .SS "Shell Variables"
 .B "SHELL BUILTIN COMMANDS"
 below).
 The characters between the insertion point and the mark are often
-called the \fIregion\fP.
+called the
+.IR region .
 .TP
 .B READLINE_POINT
 The position of the insertion point in the
@@ -2413,9 +2458,8 @@ .SS "Shell Variables"
 Set the number of exited child status values for the shell to remember.
 \fBBash\fP will not allow this value to be decreased below a
 .SM POSIX\c
--mandated
-minimum, and there is a maximum value (currently 8192) that this may
-not exceed.
+-mandated minimum,
+and there is a maximum value (currently 8192) that this may not exceed.
 The minimum value is system-dependent.
 .TP
 .B COLUMNS
@@ -2549,7 +2593,8 @@ .SS "Shell Variables"
 .Q 10 ,
 for example).
 When using \fInumeric\fP, names containing non-digits sort after all
-the all-digit names and are sorted by name using the traditional behavior.
+the all-digit names and are sorted by name using the traditional
+behavior.
 .IP
 A sort specifier of \fInosort\fP disables sorting completely;
 .B bash
@@ -2617,7 +2662,9 @@ .SS "Shell Variables"
 if necessary, to contain no more than that number of lines
 by removing the oldest entries.
 The history file is also truncated to this size after
-writing it when a shell exits or by the \fBhistory\fP builtin.
+writing it when a shell exits or by the
+.B \%history
+builtin.
 If the value is 0, the history file is truncated to zero size.
 Non-numeric values and numeric values less than zero inhibit truncation.
 The shell sets the default value to the value of
@@ -2634,7 +2681,8 @@ .SS "Shell Variables"
 it is not saved on the history list.
 Each pattern is anchored at the
 beginning of the line and must match the complete line
-(\fBbash\fP does not  implicitly append a
+.RB ( bash
+does not implicitly append a
 .Q \fB*\fP ).
 Each pattern is tested against the line
 after the checks specified by
@@ -2651,11 +2699,31 @@ .SS "Shell Variables"
 the second and subsequent lines are not tested,
 and are added to the history regardless of the value of
 .SM
-.BR HISTIGNORE .
-If the first line was not saved, the second and subsequent lines of
-the command are not saved either.
-The pattern matching honors the setting of the \fBextglob\fP shell
-option.
+.BR HISTIGNORE ,
+if the first line was saved.
+If it was not,
+the second and subsequent lines of the command are not saved either.
+The pattern matching honors the setting of the
+.B \%extglob
+shell option.
+.IP
+.SM
+.B HISTIGNORE
+subsumes some of the function of
+.SM
+.BR HISTCONTROL .
+A pattern of
+.Q &
+is identical to
+.Q \%ignoredups ,
+and a pattern of
+.Q "[ ]*"
+is identical to
+.Q \%ignorespace .
+Combining these two patterns,
+separating them with a colon,
+provides the functionality of
+.Q \%ignoreboth .
 .TP
 .B HISTSIZE
 The number of commands to remember in the command history (see
@@ -3073,24 +3141,35 @@ .SS "Shell Variables"
 this provides functionality analogous to the \fB%\fP\fIstring\fP job 
identifier.
 .TP
 .B histchars
-The two or three characters which control history expansion,
-quick substitution, and tokenization
+The two or three characters which control
+history expansion,
+quick substitution,
+and tokenization
 (see
 .SM
 .B "HISTORY EXPANSION"
 below).
-The first character is the \fIhistory expansion\fP character,
-the character which begins a history expansion, normally
-.Q \fB!\fP .
-The second character is the \fIquick substitution\fP character, normally
-.Q \fB\*^\fP .
-When it appears as the first character on the line,
+The first is the
+.Q "history expansion"
+character:
+normally
+.Q \fB!\fP ,
+it begins a history expansion.
+The second is the
+.Q "quick substitution"
+character:
+normally
+.Q \fB\*^\fP ,
+when it appears as the first character on the line,
 history substitution repeats the previous command,
 replacing one string with another.
-The optional third character is the character which indicates that
-the remainder of the line is a comment when found as the first character
-of a word, normally
-.Q \fB#\fP .
+The optional third is the
+.Q "history comment"
+character:
+normally
+.Q \fB#\fP ,
+when it appears as the first character of a word,
+it marks the remainder of the line as a comment.
 The history comment character disables history substitution
 for the remaining words on the line.
 It does not necessarily cause the shell parser to treat the rest of the
@@ -3099,41 +3178,61 @@ .SS "Shell Variables"
 .SS Arrays
 .B Bash
 provides one-dimensional indexed and associative array variables.
-Any variable may be used as an indexed array; the
+Any variable may be used as an indexed array;
+the
 .B declare
 builtin explicitly declares an array.
 There is no maximum
-limit on the size of an array, nor any requirement that members
-be indexed or assigned contiguously.
+limit on the size of an array,
+nor any requirement that members be indexed or assigned contiguously.
 Indexed arrays are referenced using arithmetic expressions
+(see
+.SM
+.B
+ARITHMETIC EVALUATION
+below)
 that must expand to an integer and are zero-based;
 associative arrays are referenced using arbitrary strings.
-Unless otherwise noted, indexed array indices must be non-negative integers.
+Unless otherwise noted,
+indexed array indices must be non-negative integers.
 .PP
 An indexed array is created automatically if any variable is assigned to
 using the syntax
-\fIname\fP[\fIsubscript\fP]=\fIvalue\fP.
+.RS
+.BI name [ subscript ]= value\c
+\&.
+.RE
 The
 .I subscript
 is treated as an arithmetic expression that must evaluate to a number
 greater than or equal to zero.
-To explicitly declare an indexed array, use
-.B declare \-a \fIname\fP
+To explicitly declare an indexed array,
+use
+.RS
+.BI "declare \-a\ " name
+.RE
 (see
 .SM
 .B "SHELL BUILTIN COMMANDS"
 below).
-.B declare \-a \fIname\fP[\fIsubscript\fP]
-is also accepted; the \fIsubscript\fP is ignored.
+.RS
+.BI "declare \-a\ " name [ subscript ]
+.RE
+is also accepted;
+the
+.I subscript
+is ignored.
 .PP
 Associative arrays are created using
-.BR "declare \-A \fIname\fP" .
+.RS
+.BI "declare \-A\ " name
+.RE
+\&.
 .PP
-Attributes may be
-specified for an array variable using the
-.B declare
+Attributes may be specified for an array variable using the
+.B \%declare
 and
-.B readonly
+.B \%readonly
 builtins.
 Each attribute applies to all members of an array.
 .PP
@@ -3182,8 +3281,11 @@ .SS Arrays
 \fIname\fP, so negative indices count back from the end of the
 array, and an index of \-1 references the last element.
 .PP
-The += operator appends to an array variable when assigning
-using the compound assignment syntax; see
+The
+.Q +=
+operator appends to an array variable
+when assigning using the compound assignment syntax;
+see
 .SM
 .B PARAMETERS
 above.
@@ -3368,21 +3470,39 @@ .SS Brace Expansion
 .Q "ade ace abe" .
 .PP
 A sequence expression takes the form
-\fB{\fP\fIx\fP\fB..\fP\fIy\fP\fB[..\fP\fIincr\fP\fB]}\fP,
-where \fIx\fP and \fIy\fP are either integers or single letters,
-and \fIincr\fP, an optional increment, is an integer.
-When integers are supplied, the expression expands to each number between
-\fIx\fP and \fIy\fP, inclusive.
-If either \fIx\fP or \fIy\fP begins with \fI0\fP,
-each generated term will contain the same number of digits,
-zero-padding where necessary.
-When either \fIx\fP or \fPy\fP begins with a zero, the shell
-attempts to force all generated terms to contain the same number of digits,
-zero-padding where necessary.
+.BI { x .. y\c
+[\c
+.I incr
+.RB ] } ,
+where
+.I x
+and
+.I y
+and
+.IR incr ,
+an optional increment, is an integer.
+When integers are supplied,
+the expression expands to each number between
+.I x
+and
+.IR y ,
+inclusive.
+If the supplied integers are prefixed with
+.Q 0 ,
+each term will have the same width,
+zero-padding if necessary.
 When letters are supplied, the expression expands to each character
-lexicographically between \fIx\fP and \fIy\fP, inclusive,
+lexicographically between
+.I x
+and
+.IR y ,
+inclusive,
 using the default C locale.
-Note that both \fIx\fP and \fIy\fP must be of the same type
+Note that both
+.I x
+and
+.I y
+must be of the same type
 (integer or letter).
 When the increment is supplied, it is used as the difference between
 each term.
@@ -3401,22 +3521,33 @@ .SS Brace Expansion
 sequence expression.
 Any incorrectly formed brace expansion is left unchanged.
 .PP
-A \fB{\fP or \fB,\fP may be quoted with a backslash to prevent its
-being considered part of a brace expression.
-To avoid conflicts with parameter expansion, the string \fB${\fP
-is not considered eligible for brace expansion, and inhibits brace
-expansion until the closing \fB}\fP.
+A
+.Q {
+or
+.Q ,
+may be quoted with a backslash
+to prevent its being considered part of a brace expression.
+To avoid conflicts with parameter expansion,
+the string
+.Q ${
+is not considered eligible for brace expansion,
+and inhibits brace expansion until the closing
+.Q } .
 .PP
 This construct is typically used as shorthand when the common
 prefix of the strings to be generated is longer than in the
 above example:
-.RS
 .PP
+.RS
+.EX
 mkdir /usr/local/src/bash/{old,new,dist,bugs}
+.EE
 .RE
 or
 .RS
+.EX
 chown root /usr/{ucb/{ex,edit},lib/{ex?.?*,how_ex}}
+.EE
 .RE
 .PP
 Brace expansion introduces a slight incompatibility with
@@ -3430,10 +3561,12 @@ .SS Brace Expansion
 expansion.
 For example, a word entered to
 .B sh
-as \fIfile{1,2}\fP
+as
+.Q file{1,2}
 appears identically in the output.
-\fBBash\fP outputs that word as
-.I file1 file2
+.B Bash
+outputs that word as
+.Q "file1 file2"
 after brace expansion.
 Start
 .B bash
@@ -3443,10 +3576,14 @@ .SS Brace Expansion
 .B +B
 option to the
 .B set
-command (see
+command
+(see
 .SM
 .B "SHELL BUILTIN COMMANDS"
-below) for strict \fBsh\fP compatibility.
+below)
+for strict
+.B sh
+compatibility.
 .SS Tilde Expansion
 If a word begins with an unquoted tilde character (\c
 .Q \fB\*~\fP ),
@@ -4145,17 +4282,30 @@ .SS Process Substitution
 passed as an argument to the current command as the result of the
 expansion.
 .PP
-If the \fB>(\fP\fIlist\^\fP\fB)\fP form is used, writing to
-the file provides input for \fIlist\fP.
 If the
-\fB<(\fP\fIlist\^\fP\fB)\fP form is used, reading the file
-obtains the output of \fIlist\fP.
-No space may appear between the \fB<\fP or \fB>\fP
-and the left parenthesis, otherwise the construct would be interpreted
-as a redirection.
+.BI >( list )
+form is used,
+writing to the file provides input for
+.I list .
+If the
+.BI <( list )
+form is used,
+reading the file obtains the output of
+.I list .
+No space may appear between the
+.B <
+or
+.B >
+and the left parenthesis;
+otherwise the construct would be interpreted as a redirection.
 .PP
-Process substitution is supported on systems that support named
-pipes (\fIFIFOs\fP) or the \fB/dev/fd\fP method of naming open files.
+Process substitution is supported on systems that support named pipes
+(\c
+.SM FIFO\c
+s)
+or the
+.I /dev/fd
+method of naming open files.
 .PP
 When available, process substitution is performed
 simultaneously with parameter and variable expansion,
@@ -4366,7 +4516,8 @@ .SS "Pathname Expansion"
 .Q .*
 one of the patterns in
 .SM
-.BR GLOBIGNORE .
+.B GLOBIGNORE \c
+\&. \" Set the period outside the reach of `SM`.
 The
 .B dotglob
 option is disabled when
@@ -4375,14 +4526,18 @@ .SS "Pathname Expansion"
 is unset.
 The
 .B GLOBIGNORE
-pattern matching honors the setting of the \fBextglob\fP shell
-option.
+pattern matching honors the setting of the
+.B \%extglob
+shell option.
 .PP
 The
 .SM
 .B GLOBSORT
-shell variable controls how the results of pathname expansion are sorted,
-as described above.
+shell variable controls
+how the results of pathname expansion are sorted,
+as described in
+.B "Shell Variables"
+above.
 .PP
 \fBPattern Matching\fP
 .PP
@@ -4715,9 +4870,11 @@ .SS Redirecting Output
 .B noclobber
 option to the
 .B set
-builtin has been enabled, the redirection fails if the file
-whose name results from the expansion of \fIword\fP exists and is
-a regular file.
+builtin has been enabled,
+the redirection fails
+if the file whose name results from the expansion of
+.I word
+exists and is a regular file.
 If the redirection operator is
 .BR >| ,
 or the redirection operator is
@@ -4727,10 +4884,12 @@ .SS Redirecting Output
 option to the
 .B set
 builtin command is not enabled,
-\fBbash\fP attempts the redirection
-even if the file named by \fIword\fP exists.
+.B bash
+attempts the redirection even if the file named by
+.I word
+exists.
 .SS Appending Redirected Output
-Redirecting  output in this fashion opens
+Redirecting output in this fashion opens
 the file whose name results from the expansion of
 .I word
 for appending on file descriptor
@@ -5162,8 +5321,10 @@ .SH FUNCTIONS
 Once the function returns, any instance of the variable at a previous
 scope becomes visible.
 If the unset acts on a variable at a previous scope, any instance of a
-variable with that name that had been shadowed becomes visible
-(see below how the \fBlocalvar_unset\fP shell option changes this behavior).
+variable with that name that had been shadowed will become visible
+(see below how the
+.B localvar_unset
+shell option changes this behavior).
 .PP
 The
 .SM
diff --git a/doc/bashref.texi b/doc/bashref.texi
index 0998411e..c8dcc142 100644
--- a/doc/bashref.texi
+++ b/doc/bashref.texi
@@ -487,10 +487,16 @@ @node Top
 If enabled, history expansion will be performed unless an
 @samp{!}
 appearing in double quotes is escaped using a backslash.
-The backslash preceding the @samp{!} is not removed.
+The backslash preceding the
+@samp{!}
+is not removed.
 
-The special parameters @samp{*} and @samp{@@} have special meaning
-when in double quotes (@pxref{Shell Parameter Expansion}).
+The special parameters
+@samp{*}
+and
+@samp{@@}
+have special meaning when in double quotes
+(@pxref{Shell Parameter Expansion}).
 
 @node ANSI-C Quoting
 @subsubsection ANSI-C Quoting
@@ -1739,10 +1745,12 @@ @node Top
 (appearing as unset)
 until it is reset in that scope or until the function returns.
 Once the function returns, any instance of the variable at a previous
-scope becomes visible.
+scope will become visible.
 If the unset acts on a variable at a previous scope, any instance of a
 variable with that name that had been shadowed will become visible
-(see below how the @code{localvar_unset} shell option changes this behavior).
+(see below how the
+@code{localvar_unset}
+shell option changes this behavior).
 
 The @option{-f} option to the @code{declare} (@code{typeset})
 builtin command (@pxref{Bash Builtins})
@@ -1819,26 +1827,41 @@ @node Top
 command export var=value
 @end example
 
-In the context where an assignment statement is assigning a value  
-to a shell variable or array index (@pxref{Arrays}),
-the @samp{+=} operator appends to or adds to
-the variable's previous value.
+In the context where an assignment statement is assigning a value
+to a shell variable or array index
+(@pxref{Arrays}),
+the
+@samp{+=}
+operator appends to or adds to the variable's previous value.
 This includes arguments to declaration commands such as
-@code{declare} that accept assignment statements.
-When @samp{+=} is applied to a variable
-for which the @code{integer} attribute has been set,
-the variable's current value and @var{value} are each evaluated as
-arithmetic expressions,
+@code{declare}
+that accept assignment statements.
+When
+@samp{+=}
+is applied to a variable
+for which the
+@code{integer}
+attribute has been set,
+the variable's current value and
+@var{value}
+are each evaluated as arithmetic expressions,
 and the sum of the results is assigned as the variable's value.
-The current value is usually an integer constant, but may be an expression.
-When @samp{+=} is applied to an array variable using compound assignment
-(@pxref{Arrays}), the
-variable's value is not unset (as it is when using @samp{=}), and new
-values are appended to the array beginning at one greater than the array's
-maximum index (for indexed arrays), or added as additional key-value pairs
-in an associative array.
-When applied to a string-valued variable, @var{value} is expanded and
-appended to the variable's value.
+The current value is usually an integer constant,
+but may be an expression.
+When
+@samp{+=}
+is applied to an array variable using compound assignment
+(@pxref{Arrays}),
+the variable's value is not unset
+(as it is when using
+@samp{=}),
+and new values are appended to the array
+beginning at one greater than the array's maximum index
+(for indexed arrays),
+or added as additional key-value pairs in an associative array.
+When applied to a string-valued variable,
+@var{value}
+is expanded and appended to the variable's value.
 
 A variable can be assigned the @code{nameref} attribute using the
 @option{-n} option to the @code{declare} or @code{local} builtin commands
@@ -2081,18 +2104,38 @@ @node Top
 ade ace abe
 @end example
 
-A sequence expression takes the form @code{@{@var{x}..@var{y}[..@var{incr}]@}},
-where @var{x} and @var{y} are either integers or letters,
-and @var{incr}, an optional increment, is an integer.
-When integers are supplied, the expression expands to each number between
-@var{x} and @var{y}, inclusive.
-If either @var{x} or @var{y} begins with a zero,
-each generated term will contain the same number of digits,
-zero-padding where necessary.
+A sequence expression takes the form
+@code{@{@var{x}..@var{y}[..@var{incr}]@}},
+where
+@var{x}
+and
+@var{y}
+are either integers or single letters,
+and
+@var{incr},
+an optional increment, is an integer.
+When integers are supplied,
+the expression expands to each number between
+@var{x}
+and
+@var{y},
+inclusive.
+If the supplied integers are prefixed with
+@samp{0},
+each term will have the same width,
+zero-padding if necessary.
 When letters are supplied, the expression expands to each character
-lexicographically between @var{x} and @var{y}, inclusive,
+lexicographically between
+@var{x}
+and
+@var{y},
+inclusive,
 using the default C locale.
-Note that both @var{x} and @var{y} must be of the same type
+Note that both
+@var{x}
+and
+@var{y}
+must be of the same type
 (integer or letter).
 When the increment is supplied, it is used as the difference between
 each term.
@@ -2110,11 +2153,18 @@ @node Top
 sequence expression.
 Any incorrectly formed brace expansion is left unchanged.
 
-A @{ or @samp{,} may be quoted with a backslash to prevent its
-being considered part of a brace expression.
-To avoid conflicts with parameter expansion, the string @samp{$@{}
+A
+@samp{@{}
+or
+@samp{,}
+may be quoted with a backslash
+to prevent its being considered part of a brace expression.
+To avoid conflicts with parameter expansion,
+the string
+@samp{$@{}
 is not considered eligible for brace expansion,
-and inhibits brace expansion until the closing @samp{@}}.
+and inhibits brace expansion until the closing
+@samp{@}}.
 
 This construct is typically used as shorthand when the common
 prefix of the strings to be generated is longer than in the
@@ -2127,6 +2177,38 @@ @node Top
 chown root /usr/@{ucb/@{ex,edit@},lib/@{ex?.?*,how_ex@}@}
 @end example
 
+Brace expansion introduces a slight incompatibility with
+historical versions of
+@command{sh}.
+@command{sh}
+does not treat opening or closing braces specially when they
+appear as part of a word, and preserves them in the output.
+Bash
+removes braces from words as a consequence of brace
+expansion.
+For example, a word entered to
+@command{sh}
+as
+@samp{file@{1,2@}}
+appears identically in the output.
+Bash
+outputs that word as
+@samp{file1 file2}
+after brace expansion.
+Start
+Bash
+with the
+@option{+B}
+option or disable brace expansion with the
+@option{+B}
+option to the
+@code{set}
+command
+(@pxref{Shell Builtin Commands})
+for strict
+@command{sh}
+compatibility.
+
 @node Tilde Expansion
 @subsection Tilde Expansion
 @cindex tilde expansion
@@ -2906,17 +2988,28 @@ @node Top
 passed as an argument to the current command as the result of the
 expansion.
 
-If the @code{>(@var{list})} form is used, writing to
-the file provides input for @var{list}.
 If the
-@code{<(@var{list})} form is used, reading the file 
-obtains the output of @var{list}.
-Note that no space may appear between the @code{<} or @code{>}
-and the left parenthesis, otherwise the construct would be interpreted
-as a redirection.
+@code{>(@var{list})}
+form is used,
+writing to the file provides input for
+@var{list}.
+If the
+@code{<(@var{list})}
+form is used,
+reading the file obtains the output of
+@var{list}.
+No space may appear between the
+@code{<}
+or
+@code{>}
+and the left parenthesis;
+otherwise the construct would be interpreted as a redirection.
 
-Process substitution is supported on systems that support named
-pipes (@sc{fifo}s) or the @file{/dev/fd} method of naming open files.
+Process substitution is supported on systems that support named pipes
+(@sc{fifo}s)
+or the
+@file{/dev/fd}
+method of naming open files.
 
 When available, process substitution is performed simultaneously with
 parameter and variable expansion, command substitution, and arithmetic
@@ -3046,17 +3139,24 @@ @node Top
 @samp{.}
 match.
 To get the old behavior of ignoring filenames beginning with a
-@samp{.}, make @samp{.*} one of the patterns in @env{GLOBIGNORE}.
-The @code{dotglob} option is disabled when @env{GLOBIGNORE}
+@samp{.},
+make @samp{.*}
+one of the patterns in
+@env{GLOBIGNORE}.
+The @code{dotglob} option is disabled when
+@env{GLOBIGNORE}
 is unset.
 The @code{GLOBIGNORE}
-pattern matching honors the setting of the @code{extglob} shell
-option.
+pattern matching honors the setting of the
+@code{extglob}
+shell option.
 
-After the pattern is expanded and matched against filenames, the value of the
-@env{GLOBSORT} shell
-variable controls how the results are sorted, as described
-below (@pxref{Bash Variables}).
+The
+@env{GLOBSORT}
+shell variable controls
+how the results of pathname expansion are sorted,
+as described below
+(@pxref{Bash Variables}).
 
 @node Pattern Matching
 @subsubsection Pattern Matching
@@ -3349,19 +3449,33 @@ @node Top
 @code{noclobber}
 option to the
 @code{set}
-builtin has been enabled, the redirection fails if the file
-whose name results from the expansion of @var{word} exists and is
-a regular file.
-If the redirection operator is @samp{>|}, or the redirection operator is
-@samp{>} and the @code{noclobber} option is not enabled,
-Bash attemps the redirection
-even if the file named by @var{word} exists.
+builtin has been enabled,
+the redirection fails
+if the file whose name results from the expansion of
+@var{word}
+exists and is a regular file.
+If the redirection operator is
+@samp{>|},
+or the redirection operator is
+@samp{>}
+and the
+@code{noclobber}
+option to the
+@code{set}
+builtin command is not enabled,
+Bash
+attemps the redirection even if the file named by
+@var{word}
+exists.
 
 @subsection Appending Redirected Output
 Redirecting output in this fashion opens
-the file whose name results from the expansion of @var{word}
-for appending on file descriptor @var{n},
-or the standard output (file descriptor 1) if @var{n}
+the file whose name results from the expansion of
+@var{word}
+for appending on file descriptor
+@var{n},
+or the standard output (file descriptor 1) if
+@var{n}
 is not specified.
 If the file does not exist it is created.
 
@@ -6912,7 +7026,8 @@ @node Top
 
 @item BASH_XTRACEFD
 If set to an integer corresponding to a valid file descriptor,
-Bash writes the trace output generated when
+Bash
+writes the trace output generated when
 @samp{set -x}
 is enabled to that file descriptor,
 instead of the standard error.
@@ -7157,9 +7272,14 @@ @node Top
 
 The @samp{numeric} specifier treats names consisting solely of digits as
 numbers and sorts them using their numeric value
-(so ``2'' sorts before ``10'', for example).
+(so
+``2''
+sorts before
+``10'',
+for example).
 When using @samp{numeric}, names containing non-digits sort after all
-the all-digit names and are sorted by name using the traditional behavior.
+the all-digit names and are sorted by name using the traditional
+behavior.
 
 A sort specifier of @samp{nosort} disables sorting completely;
 Bash returns the results
@@ -7181,20 +7301,32 @@ @node Top
 subsequently reset.
 
 @item histchars
-The two or three characters which control history expansion,
-quick substitution, and tokenization
+The two or three characters that control
+history expansion,
+quick substitution,
+and tokenization
 (@pxref{History Interaction}).
-The first character is the @dfn{history expansion} character,
-the character which begins a history expansion, normally
-@samp{!}.
-The second character is the ``quick substitution'' character, normally
-@samp{^}.
-When it appears as the first character on the line,
+The first is the
+``history expansion''
+character:@:
+normally
+@samp{!},
+it begins a history expansion.
+The second is the
+``quick substitution''
+character:@:
+normally
+@samp{^},
+when it appears as the first character on the line,
 history substitution repeats the previous command,
 replacing one string with another.
-The optional third character is the character which indicates that
-the remainder of the line is a comment when found as the first character
-of a word, usually @samp{#}.
+The optional third is the
+``history comment''
+character:@:
+normally
+@samp{#};
+when it appears as the first character of a word,
+it marks the remainder of the line as a comment.
 The history comment character disables history substitution
 for the remaining words on the line.
 It does not necessarily cause the shell parser to treat the rest of the
@@ -7244,10 +7376,13 @@ @node Top
 if necessary, to contain no more than that number of lines
 by removing the oldest entries.
 The history file is also truncated to this size after
-writing it when a shell exits or by the @code{history} builtin.
+writing it when a shell exits or by the
+@code{history}
+builtin.
 If the value is 0, the history file is truncated to zero size.
 Non-numeric values and numeric values less than zero inhibit truncation.
-The shell sets the default value to the value of @env{HISTSIZE}
+The shell sets the default value to the value of
+@env{HISTSIZE}
 after reading any startup files.
 
 @item HISTIGNORE
@@ -7258,7 +7393,8 @@ @node Top
 it is not saved on the history list.
 Each pattern is anchored at the
 beginning of the line and must match the complete line
-(Bash does not implicitly append a
+(Bash
+does not implicitly append a
 @samp{*}).
 Each pattern is tested against the line
 after the checks specified by
@@ -7273,17 +7409,29 @@ @node Top
 If the first line of a multi-line compound command was saved,
 the second and subsequent lines are not tested,
 and are added to the history regardless of the value of
-@env{HISTIGNORE}.
-If the first line was not saved, the second and subsequent lines of
-the command are not saved either.
-The pattern matching honors the setting of the @code{extglob} shell
-option.
-
-@env{HISTIGNORE} subsumes some of the function of @env{HISTCONTROL}.
-A pattern of @samp{&} is identical to @code{ignoredups}, and a
-pattern of @samp{[ ]*} is identical to @code{ignorespace}. 
-Combining these two patterns, separating them with a colon,
-provides the functionality of @code{ignoreboth}. 
+@env{HISTIGNORE},
+if the first line was saved.
+If it was not,
+the second and subsequent lines of the command are not saved either.
+The pattern matching honors the setting of the
+@code{extglob}
+shell option.
+
+@env{HISTIGNORE}
+subsumes some of the function of
+@env{HISTCONTROL}.
+A pattern of
+@samp{&}
+is identical to
+@code{ignoredups},
+and a pattern of
+@samp{[ ]*}
+is identical to
+@code{ignorespace}.
+Combining these two patterns,
+separating them with a colon,
+provides the functionality of
+@code{ignoreboth}.
 
 @item HISTSIZE
 The maximum number of commands to remember on the history list.
@@ -7498,7 +7646,8 @@ @node Top
 The current working directory as set by the @code{cd} builtin.
 
 @item RANDOM
-Each time this parameter is referenced, it expands to a random integer
+Each time this parameter is referenced,
+it expands to a random integer
 between 0 and 32767.
 Assigning a value to
 @env{RANDOM}
@@ -7510,24 +7659,34 @@ @node Top
 subsequently reset.
 
 @item READLINE_ARGUMENT
-Any numeric argument given to a Readline command that was defined using
-@samp{bind -x} (@pxref{Bash Builtins}
+Any numeric argument given to a
+Readline
+command that was defined using
+@samp{bind -x}
+(@pxref{Bash Builtins}
 when it was invoked.
 
 @item READLINE_LINE
 The contents of the Readline line buffer, for use
-with @samp{bind -x} (@pxref{Bash Builtins}).
+with
+@samp{bind -x}
+(@pxref{Bash Builtins}).
 
 @item READLINE_MARK
 The position of the @dfn{mark} (saved insertion point) in the
 Readline line buffer, for use
-with @samp{bind -x} (@pxref{Bash Builtins}).
+with
+@samp{bind -x}
+(@pxref{Bash Builtins}).
 The characters between the insertion point and the mark are often
-called the @dfn{region}.
+called the
+@dfn{region}.
 
 @item READLINE_POINT
 The position of the insertion point in the Readline line buffer, for use
-with @samp{bind -x} (@pxref{Bash Builtins}).
+with
+@samp{bind -x}
+(@pxref{Bash Builtins}).
 
 @item REPLY
 The default variable for the @code{read} builtin;
@@ -7733,8 +7892,9 @@ @node Top
 This is on by default if the shell is invoked as @code{sh}.
 
 @item --posix
-Change the behavior of Bash where the default operation differs
-from the
+Change the behavior of
+Bash
+where the default operation differs from the
 @sc{posix}
 standard to match the standard.
 This is intended to make Bash behave as a strict superset of that
@@ -7795,7 +7955,8 @@ @node Top
 through a pipe.
 
 @item -D
-Print a list of all double-quoted strings preceded by @samp{$}
+Print a list of all double-quoted strings preceded by
+@samp{$}
 on the standard output.
 These are the strings that
 are subject to language translation when the current locale
@@ -7833,28 +7994,62 @@ @node Top
 @end table
 
 @cindex login shell
-A @emph{login} shell is one whose first character of argument zero is
-@samp{-}, or one invoked with the @option{--login} option.
+A
+@dfn{login shell}
+is one whose first character of argument zero is
+@samp{-},
+or one invoked with the
+@option{--login}
+option.
 
 @cindex interactive shell
-An @emph{interactive} shell is one started without non-option arguments,
-unless @option{-s} is specified, without specifying the @option{-c} option,
-and whose input and output (using the standard error) are both
-connected to terminals (as determined by @code{isatty(3)}), or one
-started with the @option{-i} option.
+An
+@dfn{interactive}
+shell is one started without non-option arguments
+(unless
+@option{-s}
+is specified),
+without specifying the
+@option{-c}
+option,
+and whose standard input and standard error
+are both connected to terminals
+(as determined by
+@i{isatty}(3)),
+or one started with the
+@option{-i} option.
 @xref{Interactive Shells}, for more information.
 
-If arguments remain after option processing, and neither the
-@option{-c} nor the @option{-s}
-option has been supplied, the first argument is assumed to
-be the name of a file containing shell commands (@pxref{Shell Scripts}).
-When Bash is invoked in this fashion, @code{$0}
-is set to the name of the file, and the positional parameters
-are set to the remaining arguments.
-Bash reads and executes commands from this file, then exits.   
-Bash's exit status is the exit status of the last command executed
+If arguments remain after option processing,
+and neither the
+@option{-c}
+nor the
+@option{-s}
+option has been supplied,
+the first argument is assumed to be the name of a file
+containing shell commands
+(@pxref{Shell Scripts}).
+When
+Bash
+is invoked in this fashion,
+@code{$0}
+is set to the name of the file,
+and the positional parameters are set to the remaining arguments.
+Bash
+reads and executes commands from this file,
+then exits.
+Bash's
+exit status is the exit status of the last command executed
 in the script.
-If no commands are executed, the exit status is 0.
+If no commands are executed,
+the exit status is 0.
+Bash
+first attempts to open the file in the current directory,
+and,
+if no file is found,
+then searches the directories in
+@env{PATH}
+for the script.
 
 @node Bash Startup Files
 @section Bash Startup Files
@@ -7914,36 +8109,58 @@ @node Top
 but does not the value of the @env{PATH} variable to search for the
 filename.
 
-As noted above, if a non-interactive shell is invoked with the
-@option{--login} option, Bash attempts to read and execute commands from the
-login shell startup files. 
+As noted above,
+if a non-interactive shell is invoked with the
+@option{--login}
+option,
+Bash
+attempts to read and execute commands from the
+login shell startup files.
 
 @subsubheading Invoked with name @code{sh}
 
-If Bash is invoked with the name @code{sh}, it tries to mimic the
-startup behavior of historical versions of @code{sh} as closely as
-possible, while conforming to the
+If
+Bash
+is invoked with the name
+@command{sh},
+it tries to mimic the startup behavior of historical versions of
+@command{sh}
+as closely as possible,
+while conforming to the
 @sc{posix}
 standard as well.
 
-When invoked as an interactive login shell, or as a non-interactive
-shell with the @option{--login} option, it first attempts to read
-and execute commands from @file{/etc/profile} and @file{~/.profile}, in
-that order.
-The @option{--noprofile} option inhibits this behavior.
+When invoked as an interactive login shell,
+or as a non-interactive shell with the
+@option{--login}
+option,
+it first attempts to read and execute commands from
+@file{/etc/profile}
+and
+@file{~/.profile},
+in that order.
+The
+@option{--noprofile}
+option inhibits this behavior.
 
-When invoked as an interactive shell with the name @code{sh}, Bash
-looks for the variable @env{ENV}, expands its value if it is defined,
+When invoked as an interactive shell with the name
+@command{sh},
+Bash
+looks for the variable
+@env{ENV},
+expands its value if it is defined,
 and uses the expanded value as the name of a file to read and execute.
-Since a shell invoked as @code{sh} does not attempt to read and execute
-commands from any other startup files, the @option{--rcfile} option has
-no effect.
-
-A non-interactive shell invoked with the name @code{sh} does not attempt
-to read any other startup files.
+Since a shell invoked as
+@command{sh}
+does not attempt to read and execute commands from any other startup
+files,
+the
+@option{--rcfile}
+option has no effect.
 
-When invoked as @code{sh}, Bash enters @sc{posix} mode after reading
-the startup files.
+A non-interactive shell invoked with the name
+@command{sh}
+does not attempt to read any other startup files.
 
 @subsubheading Invoked in @sc{posix} mode
 
@@ -8538,16 +8755,19 @@ @node Top
 
 Bash
 provides one-dimensional indexed and associative array variables.
-Any variable may be used as an indexed array; the
+Any variable may be used as an indexed array;
+the
 @code{declare}
 builtin explicitly declares an array.
 There is no maximum
-limit on the size of an array, nor any requirement that members
-be indexed or assigned contiguously.
+limit on the size of an array,
+nor any requirement that members be indexed or assigned contiguously.
 Indexed arrays are referenced using arithmetic expressions
-that must expand to an integer (@pxref{Shell Arithmetic})) and are zero-based;
-associative arrays use arbitrary strings.
-Unless otherwise noted, indexed array indices must be non-negative integers.
+(@pxref{Shell Arithmetic})
+that must expand to an integer and are zero-based;
+associative arrays are referenced using arbitrary strings.
+Unless otherwise noted,
+indexed array indices must be non-negative integers.
 
 An indexed array is created automatically if any variable is assigned to
 using the syntax
@@ -8556,10 +8776,12 @@ @node Top
 @end example
 
 @noindent
-The @var{subscript}
+The
+@var{subscript}
 is treated as an arithmetic expression that must evaluate to a number
 greater than or equal to zero.
-To explicitly declare an array, use
+To explicitly declare an indexed array,
+use
 @example
 declare -a @var{name}
 @end example
@@ -8578,9 +8800,11 @@ @node Top
 declare -A @var{name}
 @end example
 
-Attributes may be
-specified for an array variable using the @code{declare} and
-@code{readonly} builtins.
+Attributes may be specified for an array variable using the
+@code{declare}
+and
+@code{readonly}
+builtins.
 Each attribute applies to all members of an array.
 
 Arrays are assigned using compound assignments of the form
@@ -8628,8 +8852,13 @@ @node Top
 @var{name}, so negative indices count back from the end of the
 array, and an index of -1 references the last element.
 
-The @samp{+=} operator appends to an array variable when assigning
-using the compound assignment syntax; see @ref{Shell Parameters} above.
+The
+@samp{+=}
+operator appends to an array variable
+when assigning using the compound assignment syntax;
+see
+@ref{Shell Parameters}
+above.
 
 An array element is referenced using
 @code{$@{@var{name}[@var{subscript}]@}}.
@@ -8671,7 +8900,8 @@ @node Top
 Referencing an array variable without a subscript is equivalent to
 referencing with a subscript of 0.
 Any reference to a variable using a valid subscript is valid;
-Bash creates an array if necessary.
+Bash
+creates an array if necessary.
 
 An array variable is considered set if a subscript has been assigned a
 value.
-- 
2.30.2

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