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diff --git a/man/ruby.1 b/man/ruby.1
index e2d0abdefd..bc776b8946 100644
--- a/man/ruby.1
+++ b/man/ruby.1
@@ -1,7 +1,6 @@
.\"Ruby is copyrighted by Yukihiro Matsumoto <matz@netlab.jp>.
-.Dd October 25, 2008
-.Dt RUBY(1) "" "Ruby Programmers Reference Guide"
-.\".Dt RUBY 1
+.Dd March 27, 2026
+.Dt RUBY 1 "Ruby Programmer's Reference Guide"
.Os UNIX
.Sh NAME
.Nm ruby
@@ -14,30 +13,31 @@
.Op Fl 0 Ns Op Ar octal
.Op Fl C Ar directory
.Op Fl E Ar external Ns Op : Ns Ar internal
-.Op Fl F Ar pattern
+.Op Fl F Ns Op Ar pattern
.Op Fl I Ar directory
-.Op Fl K Ar c
+.Op Fl K Ns Op Ar c
.Op Fl T Ns Op Ar level
.Op Fl W Ns Op Ar level
.Op Fl e Ar command
.Op Fl i Ns Op Ar extension
.Op Fl r Ar library
.Op Fl x Ns Op Ar directory
-.Op - Ns Bro Cm enable Ns | Ns Cm disable Brc Ns - Ns Ar FEATURE
+.Op Fl - Ns Bro Cm enable Ns | Ns Cm disable Brc Ns - Ns Ar FEATURE
.Op Fl -dump Ns = Ns Ar target
.Op Fl -verbose
+.Op Fl -crash-report Ns = Ns Ar template
.Op Fl -
.Op Ar program_file
.Op Ar argument ...
.Sh DESCRIPTION
Ruby is an interpreted scripting language for quick and easy
object-oriented programming. It has many features to process text
-files and to do system management tasks (as in Perl). It is simple,
+files and to do system management tasks (like in Perl). It is simple,
straight-forward, and extensible.
.Pp
If you want a language for easy object-oriented programming, or you
don't like the Perl ugliness, or you do like the concept of LISP, but
-don't like too much parentheses, Ruby may be the language of your
+don't like too many parentheses, Ruby might be your language of
choice.
.Sh FEATURES
Ruby's features are as follows:
@@ -53,7 +53,7 @@ time check.
.Pp
.It Sy "No declaration needed"
You can use variables in your Ruby programs without any declarations.
-Variable names denote their scope, local, global, instance, etc.
+Variable names denote their scope - global, class, instance, or local.
.Pp
.It Sy "Simple syntax"
Ruby has a simple syntax influenced slightly from Eiffel.
@@ -64,11 +64,11 @@ from anywhere are automatically collected by the garbage collector
built into the interpreter.
.Pp
.It Sy "Everything is an object"
-Ruby is the purely object-oriented language, and was so since its
+Ruby is a purely object-oriented language, and was so since its
creation. Even such basic data as integers are seen as objects.
.Pp
.It Sy "Class, inheritance, and methods"
-Of course, as an object-oriented language, Ruby has such basic
+Being an object-oriented language, Ruby naturally has basic
features like classes, inheritance, and methods.
.Pp
.It Sy "Singleton methods"
@@ -81,7 +81,7 @@ to.
.It Sy "Mix-in by modules"
Ruby intentionally does not have the multiple inheritance as it is a
source of confusion. Instead, Ruby has the ability to share
-implementations across the inheritance tree. This is often called
+implementations across the inheritance tree. This is often called a
.Sq Mix-in .
.Pp
.It Sy "Iterators"
@@ -90,21 +90,21 @@ Ruby has iterators for loop abstraction.
.It Sy "Closures"
In Ruby, you can objectify the procedure.
.Pp
-.It Sy "Text processing and regular expression"
+.It Sy "Text processing and regular expressions"
Ruby has a bunch of text processing features like in Perl.
.Pp
.It Sy "M17N, character set independent"
Ruby supports multilingualized programming. Easy to process texts
-written in many different natural languages and encoded in many
+written in many different natural languages and encoded in many
different character encodings, without dependence on Unicode.
.Pp
.It Sy "Bignums"
With built-in bignums, you can for example calculate factorial(400).
.Pp
-.It Sy "Reflection and domain specific languages"
-Class is also an instance of Class class. Definition of classes and methods
-is just an expression as 1+1 is. So your programs can even write and modify programs.
-Thus you can write your application in your own programming language on top of Ruby.
+.It Sy "Reflection and domain-specific languages"
+Class is also an instance of the Class class. Definition of classes and methods
+is an expression just as 1+1 is. So your programs can even write and modify programs.
+Thus, you can write your application in your own programming language on top of Ruby.
.Pp
.It Sy "Exception handling"
As in Java(tm).
@@ -120,25 +120,36 @@ On most
systems, you can load object files into the Ruby interpreter
on-the-fly.
.It Sy "Rich libraries"
-Libraries called "builtin libraries" and "standard libraries" are bundled with Ruby.
-And you can obtain more libraries via the package management system called `RubyGems'.
-
-Moreover there are thousands of Ruby projects in Rubyforge
-.Pf ( "http://www.rubyforge.org" ) and RAA
-.Pf ( "http://raa.ruby-lang.org" ) Ns .
+In addition to the
+.Dq builtin libraries
+and
+.Dq standard libraries
+that are bundled with Ruby, a vast amount of third-party libraries
+.Pq Dq gems
+are available via the package management system called
+.Sq RubyGems ,
+namely the
+.Xr gem 1
+command. Visit RubyGems.org
+.Pq Lk https://rubygems.org/
+to find the gems you need, and explore GitHub
+.Pq Lk https://github.com/
+to see how they are being developed and used.
.El
.Pp
.Sh OPTIONS
-Ruby interpreter accepts following command-line options (switches).
+The Ruby interpreter accepts the following command-line options (switches).
They are quite similar to those of
.Xr perl 1 .
.Bl -tag -width "1234567890123" -compact
.Pp
.It Fl -copyright
-Prints the copyright notice.
+Prints the copyright notice, and quits immediately without running any
+script.
.Pp
.It Fl -version
-Prints the version of Ruby interpreter.
+Prints the version of the Ruby interpreter, and quits immediately without
+running any script.
.Pp
.It Fl 0 Ns Op Ar octal
(The digit
@@ -160,10 +171,14 @@ Causes Ruby to switch to the directory.
.It Fl E Ar external Ns Op : Ns Ar internal
.It Fl -encoding Ar external Ns Op : Ns Ar internal
Specifies the default value(s) for external encodings and internal encoding. Values should be separated with colon (:).
-
-You can ommit the one for internal encodings, then the value
+.Pp
+You can omit the one for internal encodings, then the value
.Pf ( Li "Encoding.default_internal" ) will be nil.
.Pp
+.It Fl -external-encoding Ns = Ns Ar encoding
+.It Fl -internal-encoding Ns = Ns Ar encoding
+Specify the default external or internal character encoding
+.Pp
.It Fl F Ar pattern
Specifies input field separator
.Pf ( Li "$;" ) .
@@ -177,7 +192,7 @@ will be added to the load-path variable
Specifies KANJI (Japanese) encoding. The default value for script encodings
.Pf ( Li "__ENCODING__" ) and external encodings ( Li "Encoding.default_external" ) will be the specified one.
.Ar kcode
-can be one of
+can be one of
.Bl -hang -offset indent
.It Sy e
EUC-JP
@@ -195,7 +210,7 @@ ASCII-8BIT (BINARY)
.It Fl S
Makes Ruby use the
.Ev PATH
-environment variable to search for script, unless if its name begins
+environment variable to search for script, unless its name begins
with a slash. This is used to emulate
.Li #!
on machines that don't support it, in the following manner:
@@ -205,15 +220,27 @@ on machines that don't support it, in the following manner:
exec /usr/local/bin/ruby -S $0 $*
.Ed
.Pp
-.It Fl T Ns Op Ar level
+On some systems
+.Li "$0"
+does not always contain the full pathname, so you need the
+.Fl S
+switch to tell Ruby to search for the script if necessary (to handle embedded
+spaces and such). A better construct than
+.Li "$*"
+would be
+.Li ${1+"$@"} ,
+but it does not work if the script is being interpreted by
+.Xr csh 1 .
+.Pp
+.It Fl T Ns Op Ar level=1
Turns on taint checks at the specified level (default 1).
.Pp
.It Fl U
-Sets the defalut value for internal encodings
+Sets the default value for internal encodings
.Pf ( Li "Encoding.default_internal" ) to UTF-8.
.Pp
-.It Fl W Ns Op Ar level
-Turns on verbose mode at the specified level, without printing version
+.It Fl W Ns Op Ar level=2
+Turns on verbose mode at the specified level without printing the version
message at the beginning. The level can be;
.Bl -hang -offset indent
.It Sy 0
@@ -231,7 +258,7 @@ Verbose mode is "verbose". It sets the
.Li "$VERBOSE"
to true.
.Fl W Ns
-2 is same as
+2 is the same as
.Fl w
.
.El
@@ -245,6 +272,11 @@ In auto-split mode, Ruby executes
.Dl $F = $_.split
at beginning of each loop.
.Pp
+.It Fl -backtrace-limit Ns = Ns Ar num
+Limits the maximum length of backtraces to
+.Ar num
+lines (default -1, meaning no limit).
+.Pp
.It Fl c
Causes Ruby to check the syntax of the script and exit without
executing. If there are no syntax errors, Ruby will print
@@ -255,11 +287,13 @@ to the standard output.
.It Fl -debug
Turns on debug mode.
.Li "$DEBUG"
+and
+.Li "$VERBOSE"
will be set to true.
.Pp
.It Fl e Ar command
Specifies script from command-line while telling Ruby not to search
-the rest of arguments for a script file name.
+the rest of the arguments for a script file name.
.Pp
.It Fl h
.It Fl -help
@@ -287,7 +321,7 @@ Enables automatic line-ending processing, which means to firstly set
to the value of
.Li "$/" ,
and secondly chops every line read using
-.Li chop! .
+.Li chomp! .
.Pp
.It Fl n
Causes Ruby to assume the following loop around your script, which
@@ -330,20 +364,8 @@ and set the corresponding variable in the script. For example:
print "true\en" if $xyz
.Ed
.Pp
-On some systems
-.Li "$0"
-does not always contain the full pathname, so you need the
-.Fl S
-switch to tell Ruby to search for the script if necessary. To handle
-embedded spaces or such. A better construct than
-.Li "$*"
-would be
-.Li ${1+"$@"} ,
-but it does not work if the script is being interpreted by
-.Xr csh 1 .
-.Pp
.It Fl v
-Enables verbose mode. Ruby will print its version at the beginning,
+Enables verbose mode. Ruby will print its version at the beginning
and set the variable
.Li "$VERBOSE"
to true. Some methods print extra messages if this variable is true.
@@ -358,33 +380,32 @@ variable to true.
.Pp
.It Fl x Ns Op Ar directory
Tells Ruby that the script is embedded in a message. Leading garbage
-will be discarded until the first that starts with
+will be discarded until the first line that starts with
.Dq #!
and contains the string,
.Dq ruby .
-Any meaningful switches on that line will applied. The end of script
+Any meaningful switches on that line will be applied. The end of the script
must be specified with either
.Li EOF ,
.Li "^D" ( Li "control-D" ) ,
.Li "^Z" ( Li "control-Z" ) ,
-or reserved word
+or the reserved word
.Li __END__ .
If the directory name is specified, Ruby will switch to that directory
before executing script.
.Pp
.It Fl y
.It Fl -yydebug
-DO NOT USE.
-
+This option is not guaranteed to be compatible.
+.Pp
Turns on compiler debug mode. Ruby will print a bunch of internal
-state messages during compiling scripts. You don't have to specify
-this switch, unless you are going to debug the Ruby interpreter.
+state messages during compilation. Only specify this switch you are going to
+debug the Ruby interpreter.
.Pp
.It Fl -disable- Ns Ar FEATURE
.It Fl -enable- Ns Ar FEATURE
Disables (or enables) the specified
-.Ar FEATURE Ns
-\&.
+.Ar FEATURE .
.Bl -tag -width "--disable-rubyopt" -compact
.It Fl -disable-gems
.It Fl -enable-gems
@@ -406,30 +427,63 @@ Disables (or enables) all features.
.El
.Pp
.It Fl -dump Ns = Ns Ar target
-DO NOT USE.
-
+Dump some information.
+.Pp
Prints the specified target.
.Ar target
-can be one of;
-.Bl -hang -offset indent
-.It Sy insns
-disassembed instructions
+can be one of:
+.Bl -hang -offset indent -width "version"
+.It Sy version
+Print version description (same as
+.Fl -version).
+.It Sy usage
+Print a brief usage message (same as
+.Fl h).
+.It Sy help
+Show long help message (same as
+.Fl -help).
+.It Sy syntax
+Check syntax (same as
+.Fl c
+.Fl -yydebug).
.Pp
.El
.Pp
-You don't have to specify this switch, unless you are going to debug the Ruby interpreter.
+Or one of the following, which are intended for debugging the interpreter:
+.Bl -hang -offset indent -width "parsetree"
+.It Sy yydebug
+Enable compiler debug mode (same as
+.Fl -yydebug).
+.It Sy parsetree
+Print a textual representation of the Ruby AST for the program.
+.It Sy insns
+Print a list of disassembled bytecode instructions.
+.It Sy -optimize
+Disable various optimizations to print a list disassembled bytecode instructions.
+.It Sy +error-tolerant
+Enable error-tolerant parsing, when yydebug or parsetree.
+.It Sy +comment
+Annotate a textual representation of the Ruby AST for the program with the associated Ruby source code.
+.El
.Pp
.It Fl -verbose
Enables verbose mode without printing version message at the
beginning. It sets the
.Li "$VERBOSE"
variable to true.
-If this switch is given, and no other switches are present, Ruby quits
-after printing its version.
+If this switch is given, and no script arguments (script file or
+.Fl e
+options) are present, Ruby quits immediately.
+.Pp
+.It Fl -crash-report Ns = Ns Ar template
+Sets the template of path name to save crash report.
+See
+.Ev RUBY_CRASH_REPORT
+environment variable for details.
.El
.Pp
.Sh ENVIRONMENT
-.Bl -tag -width "RUBYLIB_PREFIX" -compact
+.Bl -tag -width "RUBYSHELL" -compact
.It Ev RUBYLIB
A colon-separated list of directories that are added to Ruby's
library load path
@@ -465,47 +519,319 @@ enabled for only mswin32, mingw32, and OS/2 platforms. If this
variable is not defined, Ruby refers to
.Ev COMSPEC .
.Pp
+.It Ev RUBY_FREE_AT_EXIT
+If set, Ruby tries to free all dynamically allocated memories.
+Introduced in Ruby 3.3, default: unset.
+.Pp
+.It Ev RUBY_BOX
+If set to
+.Li 1 ,
+Ruby Box is enabled and users will be able to execute
+.Li Ruby::Box.new .
+Ruby Box is an experimental feature introduced in Ruby 4.0.
+.Pp
+.It Ev RUBY_IO_BUFFER_DEFAULT_SIZE
+The custom default buffer size of
+.Li IO::Buffer .
+.Pp
+.It Ev RUBY_MAX_CPU
+The maximum number of native threads used by M:N Threads scheduler
+Introduced in Ruby 3.3, default: 8.
+.Pp
+.It Ev RUBY_MN_THREADS
+If set to
+.Li 1 ,
+M:N Thread scheduler is enabled on the main Ractor.
+Introduced in Ruby 3.3, default: unset.
+.Pp
+.It Ev RUBY_PAGER
+The pager command that will be used for
+.Fl -help
+option.
+Introduced in Ruby 3.0, default:
+.Ev PAGER
+environment variable.
+.Pp
+.It Ev RUBY_THREAD_TIMESLICE
+Sets the default thread time slice (thread quantum) in milliseconds.
+Introduced in Ruby 3.4, default: 100ms.
+.Pp
.It Ev PATH
Ruby refers to the
.Ev PATH
environment variable on calling Kernel#system.
-.Pp
-.It Ev RUBYLIB_PREFIX
-This variable is obsolete.
.El
.Pp
-And Ruby depends on some RubyGems related environment variables unless disabled RubyGems.
+And Ruby depends on some RubyGems related environment variables unless RubyGems is disabled.
See the help of
.Xr gem 1
-as bellow.
+as below.
.Bd -literal -offset indent
% gem help
.Ed
.Pp
+.Sh GC ENVIRONMENT
+The Ruby garbage collector (GC) tracks objects in fixed-sized slots,
+but each object may have auxiliary memory allocations handled by the
+malloc family of C standard library calls (
+.Xr malloc 3 ,
+.Xr calloc 3 ,
+and
+.Xr realloc 3 ) .
+In this documentation, the "heap" refers to the Ruby object heap
+of fixed-sized slots, while "malloc" refers to auxiliary
+allocations commonly referred to as the "process heap".
+Thus there are at least two possible ways to trigger GC:
+.Bl -hang -offset indent
+.It Sy 1
+Reaching the object limit.
+.It Sy 2
+Reaching the malloc limit.
+.Pp
+.El
+In Ruby 2.1, the generational GC was introduced and the limits are divided
+into young and old generations, providing two additional ways to trigger
+a GC:
+.Bl -hang -offset indent
+.It Sy 3
+Reaching the old object limit.
+.It Sy 4
+Reaching the old malloc limit.
+.El
+.Pp
+There are currently 4 possible areas where the GC may be tuned by
+the following environment variables:
+.Bl -hang -compact -width "RUBY_GC_HEAP_n_INIT_SLOTS"
+.Pp
+.It Ev RUBY_GC_HEAP_ Ns Ar n Ns Ev _INIT_SLOTS
+Initial allocation of slots in a specific heap.
+The available heaps can be found in the keys of
+.Li GC.stat_heap .
+.Ar n
+is a decimal number between 0 and 4.
+Introduced in Ruby 3.3.
+.Pp
+.It Ev RUBY_GC_HEAP_FREE_SLOTS
+Prepare at least this amount of slots after GC.
+Allocate this number slots if there are not enough slots.
+Introduced in Ruby 2.1, default: 4096
+.Pp
+.It Ev RUBY_GC_HEAP_GROWTH_FACTOR
+Increase allocation rate of heap slots by this factor.
+Introduced in Ruby 2.1, default: 1.8, minimum: 1.0 (no growth)
+.Pp
+.It Ev RUBY_GC_HEAP_GROWTH_MAX_SLOTS
+Allocation rate is limited to this number of slots,
+preventing excessive allocation due to RUBY_GC_HEAP_GROWTH_FACTOR.
+Introduced in Ruby 2.1, default: 0 (no limit)
+.Pp
+.It Ev RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR
+Perform a full GC when the number of old objects is more than R * N,
+where R is this factor and N is the number of old objects after the
+last full GC.
+Introduced in Ruby 2.1.1, default: 2.0
+.Pp
+.It Ev RUBY_GC_HEAP_REMEMBERED_WB_UNPROTECTED_OBJECTS_LIMIT_RATIO
+Used to calculate the
+.Li remembered_wb_unprotected_objects_limit
+using a ratio of
+.Li old_objects .
+Introduced in Ruby 3.3, default: 0.1, minimum: 0.0
+.It Ev RUBY_GC_MALLOC_LIMIT
+The initial limit of young generation allocation from the malloc-family.
+GC will start when this limit is reached.
+Default: 16MB
+.Pp
+.It Ev RUBY_GC_MALLOC_LIMIT_MAX
+The maximum limit of young generation allocation from malloc before GC starts.
+Prevents excessive malloc growth due to RUBY_GC_MALLOC_LIMIT_GROWTH_FACTOR.
+Introduced in Ruby 2.1, default: 32MB.
+.Pp
+.It Ev RUBY_GC_MALLOC_LIMIT_GROWTH_FACTOR
+Increases the limit of young generation malloc calls, reducing
+GC frequency but increasing malloc growth until RUBY_GC_MALLOC_LIMIT_MAX
+is reached.
+Introduced in Ruby 2.1, default: 1.4, minimum: 1.0 (no growth)
+.Pp
+.It Ev RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO
+Allocate additional pages when the number of free slots is
+lower than the value
+.Li (total_slots * (this ratio)) .
+Introduced in Ruby 2.4, default: 0.2, minimum: 0.0, maximum: 1.0
+.Pp
+.It Ev RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO
+Allow to free pages when the number of free slots is greater than the value
+.Li (total_slots * (this ratio)) .
+Introduced in Ruby 2.4, default: 0.4, minimum:
+.Li RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO,
+maximum: 1.0
+.Pp
+.It Ev RUBY_GC_HEAP_FREE_SLOTS_GOAL_RATIO
+Allocate slots to satisfy this formula:
+.Li free_slots = total_slots * goal_ratio
+In other words, prepare
+.Li (total_slots * goal_ratio)
+free slots.
+if this value is 0.0, then use RUBY_GC_HEAP_GROWTH_FACTOR directly.
+Introduced in Ruby 2.4, default: 0.65, minimum:
+.Li RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO,
+maximum:
+.Li RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO
+.Pp
+.It Ev RUBY_GC_OLDMALLOC_LIMIT
+The initial limit of old generation allocation from malloc,
+a full GC will start when this limit is reached.
+Introduced in Ruby 2.1, default: 16MB
+.Pp
+.It Ev RUBY_GC_OLDMALLOC_LIMIT_MAX
+The maximum limit of old generation allocation from malloc before a
+full GC starts.
+Prevents excessive malloc growth due to RUBY_GC_OLDMALLOC_LIMIT_GROWTH_FACTOR.
+Introduced in Ruby 2.1, default: 128MB
+.Pp
+.It Ev RUBY_GC_OLDMALLOC_LIMIT_GROWTH_FACTOR
+Increases the limit of old generation malloc allocation, reducing full
+GC frequency but increasing malloc growth until RUBY_GC_OLDMALLOC_LIMIT_MAX
+is reached.
+Introduced in Ruby 2.1, default: 1.2, minimum: 1.0 (no growth)
+.Pp
+.It Ev RUBY_SHARED_FIBER_POOL_FREE_STACKS
+Frees stacks of pooled fibers, if set to 1.
+Do not free the stacks if set to 0.
+Introduced in Ruby 2.7, default: 1 (no growth)
+.Pp
+.It Ev RUBY_SHARED_FIBER_POOL_MAXIMUM_COUNT
+If set to a non-negative integer, the shared fiber pool cannot allocate more
+than that many stacks; further fiber creation may fail with
+.Va FiberError .
+Unset or 0 means no explicit cap (subject to process limits).
+.Pp
+.It Ev RUBY_SHARED_FIBER_POOL_MINIMUM_COUNT
+Initial and minimum growth chunk size for the shared fiber pool (stacks).
+Unset uses the implementation default.
+.Pp
+.El
+.Sh STACK SIZE ENVIRONMENT
+Stack size environment variables are implementation-dependent and
+subject to change with different versions of Ruby. The VM stack is used
+for pure-Ruby code and managed by the virtual machine. Machine stack is
+used by the operating system and its usage is dependent on C extensions
+as well as C compiler options. Using lower values for these may allow
+applications to keep more Fibers or Threads running; but increases the
+chance of SystemStackError exceptions and segmentation faults (SIGSEGV).
+These environment variables are available since Ruby 2.0.0.
+All values are specified in bytes.
+.Pp
+.Bl -hang -compact -width "RUBY_THREAD_MACHINE_STACK_SIZE"
+.It Ev RUBY_THREAD_VM_STACK_SIZE
+VM stack size used at thread creation.
+default: 524288 (32-bit CPU) or 1048576 (64-bit)
+.Pp
+.It Ev RUBY_THREAD_MACHINE_STACK_SIZE
+Machine stack size used at thread creation.
+default: 524288 or 1048576
+.Pp
+.It Ev RUBY_FIBER_VM_STACK_SIZE
+VM stack size used at fiber creation.
+default: 65536 or 131072
+.Pp
+.It Ev RUBY_FIBER_MACHINE_STACK_SIZE
+Machine stack size used at fiber creation.
+default: 262144 or 524288
+.Pp
+.El
+.Sh CRASH REPORT ENVIRONMENT
+.Pp
+.Bl -tag -compact -width "RUBY_CRASH_REPORT"
+.It Ev RUBY_CRASH_REPORT
+The template of path name to save crash report.
+default: none
+.El
+.Ss Naming crash report files
+The template can contain
+.Li \fB%\fP
+specifiers which are substituted by the following values when a crash
+report file is created:
+.Pp
+.Bl -hang -compact -width "%NNN"
+.It Li \fB%%\fP
+A single
+.Li \fB%\fP
+character.
+.It Li \fB%e\fP
+Basename of executable.
+.It Li \fB%E\fP
+Pathname of executable,
+with slashes (\fB/\fP) replaced by exclamation marks (\fB!\fP).
+.It Li \fB%f\fP
+Basename of the program name,
+.Li "$0" .
+.It Li \fB%F\fP
+Pathname of the program name,
+.Li "$0",
+with slashes (\fB/\fP) replaced by exclamation marks (\fB!\fP).
+.It Li \fB%p\fP
+PID of dumped process.
+.It Li \fB%t\fP
+Time of dump, expressed as seconds since the
+Epoch, 1970-01-01 00:00:00 +0000 (UTC).
+.It Li \fB%NNN\fP
+A character code in octal.
+.El
+.Pp
+A single
+.Li \fB%\fP
+at the end of the template is dropped from the core filename, as is
+the combination of a
+.Li \fB%\fP
+followed by any character other than those listed above. All other
+characters in the template become a literal part of the core filename.
+The template may include \(aq/\(aq characters, which are interpreted
+as delimiters for directory names.
+.Ss Piping crash reports to a program
+If the first character of this file is a pipe symbol (\fB|\fP),
+then the remainder of the line is interpreted as the command-line for
+a program (or script) that is to be executed.
+.Pp
+The pipe template is split on spaces into an argument list before the
+template parameters are expanded.
+.Sh MISC ENVIRONMENT
+.Pp
+.Bl -hang -compact -width "RUBY_TCP_NO_FAST_FALLBACK"
+.It Ev RUBY_TCP_NO_FAST_FALLBACK
+If set to
+.Li 1 ,
+disables the fast fallback feature by default in TCPSocket.new and Socket.tcp.
+When set to
+.Li 0
+or left unset, the fast fallback feature is enabled.
+Introduced in Ruby 3.4, default: unset.
.Sh SEE ALSO
-.Bl -hang -compact -width "http://www.ruby-lang.org/123"
-.It http://www.ruby-lang.org
+.Bl -hang -compact -width "https://www.ruby-toolbox.com/"
+.It Lk https://www.ruby-lang.org/
The official web site.
-.It http://www.rubyforge.org
-hosting many open source ruby projects.
-.It http://raa.ruby-lang.org
-Ruby Application Archive.
+.It Lk https://www.ruby-toolbox.com/
+Comprehensive catalog of Ruby libraries.
.El
.Pp
.Sh REPORTING BUGS
.Bl -bullet
-.Li Security vulnerabilities should be reported via an email to
-.Aq security@ruby-lang.org Ns
-.Li .
-Reported problems will be published after fixed.
-.Pp
-.Li And you can report other bugs and feature requests via the
-Ruby Issue Tracking System (http://redmine.ruby-lang.org).
+.It
+Security vulnerabilities should be reported via an email to
+.Mt security@ruby-lang.org .
+Reported problems will be published after being fixed.
+.Pp
+.It
+Other bugs and feature requests can be reported via the
+Ruby Issue Tracking System
+.Pq Lk https://bugs.ruby-lang.org/ .
Do not report security vulnerabilities
-via the system because it publishes the vulnerabilities immedately.
+via this system because it publishes the vulnerabilities immediately.
.El
.Sh AUTHORS
Ruby is designed and implemented by
.An Yukihiro Matsumoto Aq matz@netlab.jp .
-
-See <\fBhttp://redmine.ruby-lang.org/wiki/ruby/Contributors\fR> for contributors to Ruby.
+.Pp
+See
+.Aq Lk https://github.com/ruby/ruby/graphs/contributors
+for contributors to Ruby.