shell options - BASH W10 (shopt) johnmeister.com

SHELL BUILTIN COMMANDS - shopt (from W10 BASH man page)

SHELL BUILTIN COMMANDS - shopt (from W10 BASH man page): shopt [-pqsu] [-o] [optname ...]
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** - indicates current use (on)
++ - considering use
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--> shopt | grep on # (some are set by DEFAULT)
checkwinsize on / cmdhist on / complete_fullquote on
expand_aliases on / extglob on / extquote on
force_fignore on / histverify on / interactive_comments on
login_shell on / progcomp on / promptvars on
sourcepath on
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The list of shopt options is:
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autocd
If set, a command name that is the name of a directory is executed as if it
were the argument to the cd command. This option is only used by interactive shells.

cdable_vars
If set, an argument to the cd builtin command that is not a directory is
assumed to be the name of a variable whose value is the directory to change to.

++ cdspell
If set, minor errors in the spelling of a directory component in a cd com-
mand will be corrected. The errors checked for are transposed characters,
a missing character, and one character too many. If a correction is found,
the corrected filename is printed, and the command proceeds. This option
is only used by interactive shells.

checkhash
If set, bash checks that a command found in the hash table exists before
trying to execute it. If a hashed command no longer exists, a normal path
search is performed.

checkjobs
If set, bash lists the status of any stopped and running jobs before exit-
ing an interactive shell. If any jobs are running, this causes the exit to
be deferred until a second exit is attempted without an intervening command
(see JOB CONTROL). The shell always postpones exiting if any jobs are stopped.

** checkwinsize
If set, bash checks the window size after each command and, if necessary,
updates the values of LINES and COLUMNS.

** cmdhist If set, bash attempts to save all lines of a multiple-line command in the
same history entry. This allows easy re-editing of multi-line commands.

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compat31 compat32 compat40 compat41 compat42
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** complete_fullquote
If set, bash quotes all shell metacharacters in filenames and directory
names when performing completion. If not set, bash removes metacharacters
such as the dollar sign from the set of characters that will be quoted in
completed filenames when these metacharacters appear in shell variable ref-
erences in words to be completed. This means that dollar signs in variable
names that expand to directories will not be quoted; however, any dollar
signs appearing in filenames will not be quoted, either. This is active
only when bash is using backslashes to quote completed filenames. This
variable is set by DEFAULT, which is the DEFAULT bash behavior in versions through 4.2.

++ direxpand
If set, bash replaces directory names with the results of word expansion
when performing filename completion. This changes the contents of the
readline editing buffer. If not set, bash attempts to preserve what the user typed.

++ dirspell
If set, bash attempts spelling correction on directory names during word
completion if the directory name initially supplied does not exist.

dotglob If set, bash includes filenames beginning with a `.' in the results of pathname expansion.

execfail
If set, a non-interactive shell will not exit if it cannot execute the file
specified as an argument to the exec builtin command. An interactive shell
does not exit if exec fails.

** expand_aliases
If set, aliases are expanded as described above under ALIASES. This option
is enabled by DEFAULT for interactive shells.

extdebug
If set, behavior intended for use by debuggers is enabled:
1. The -F option to the declare builtin displays the source file name
and line number corresponding to each function name supplied as an
argument.
2. If the command run by the DEBUG trap returns a non-zero value, the
next command is skipped and not executed.
3. If the command run by the DEBUG trap returns a value of 2, and the
shell is executing in a subroutine (a shell function or a shell
script executed by the . or source builtins), a call to return is
simulated.
4. BASH_ARGC and BASH_ARGV are updated as described in their descrip-
tions above.
5. Function tracing is enabled: command substitution, shell functions,
and subshells invoked with ( command ) inherit the DEBUG and RETURN
traps.
6. Error tracing is enabled: command substitution, shell functions,
and subshells invoked with ( command ) inherit the ERR trap.

** extglob If set, the extended pattern matching features described under Pathname Expansion are enabled.

extquote
If set, $'string' and $"string" quoting is performed within ${parameter}
expansions enclosed in double quotes. This option is enabled by DEFAULT.

failglob
If set, patterns which fail to match filenames during pathname expansion
result in an expansion error.

** force_fignore
If set, the suffixes specified by the FIGNORE shell variable cause words to
be ignored when performing word completion even if the ignored words are
the only possible completions. See SHELL VARIABLES above for a description
of FIGNORE. This option is enabled by DEFAULT.

globasciiranges
If set, range expressions used in pattern matching bracket expressions (see
Pattern Matching above) behave as if in the traditional C locale when per-
forming comparisons. That is, the current locale's collating sequence is
not taken into account, so b will not collate between A and B, and upper-
case and lower-case ASCII characters will collate together.

globstar
If set, the pattern ** used in a pathname expansion context will match all
files and zero or more directories and subdirectories. If the pattern is
followed by a /, only directories and subdirectories match.

gnu_errfmt
If set, shell error messages are written in the standard GNU error message format.

histappend
If set, the history list is appended to the file named by the value of the
HISTFILE variable when the shell exits, rather than overwriting the file.

histreedit
If set, and readline is being used, a user is given the opportunity to re-
edit a failed history substitution.

** histverify
If set, and readline is being used, the results of history substitution are
not immediately passed to the shell parser. Instead, the resulting line is
loaded into the readline editing buffer, allowing further modification.

** hostcomplete
If set, and readline is being used, bash will attempt to perform hostname
completion when a word containing a @ is being completed (see Completing
under RE LINE above). This is enabled by DEFAULT.

huponexit
If set, bash will send SIGHUP to all jobs when an interactive login shell exits.

** interactive_comments
If set, allow a word beginning with # to cause that word and all remaining
characters on that line to be ignored in an interactive shell (see COMMENTS
above). This option is enabled by DEFAULT.

lastpipe
If set, and job control is not active, the shell runs the last command of a
pipeline not executed in the background in the current shell environment.

lithist If set, and the cmdhist option is enabled, multi-line commands are saved to
the history with embedded newlines rather than using semicolon separators
where possible.

** login_shell
The shell sets this option if it is started as a login shell (see INVOCATION ). The value may not be changed.

mailwarn
If set, and a file that bash is checking for mail has been accessed since
the last time it was checked, the message ``The mail in mailfile has been read'' is displayed.

no_empty_cmd_completion
If set, and readline is being used, bash will not attempt to search the
PATH for possible completions when completion is attempted on an empty line.

nocaseglob
If set, bash matches filenames in a case-insensitive fashion when perform-
ing pathname expansion (see Pathname Expansion above).

nocasematch
If set, bash matches patterns in a case-insensitive fashion when performing
matching while executing case or [[ conditional commands.

nullglob
If set, bash allows patterns which match no files (see Pathname Expansion
above) to expand to a null string, rather than themselves.

** progcomp
If set, the programmable completion facilities (see Programmable Completion
above) are enabled. This option is enabled by DEFAULT.

** promptvars
If set, prompt strings undergo parameter expansion, command substitution,
arithmetic expansion, and quote removal after being expanded as described
in PROMPTING above. This option is enabled by DEFAULT.

restricted_shell
The shell sets this option if it is started in restricted mode (see
RESTRICTED SHELL). The value may not be changed. This is not reset
when the startup files are executed, allowing the startup files to discover
whether or not a shell is restricted.

shift_verbose
If set, the shift builtin prints an error message when the shift count
exceeds the number of positional parameters.

** sourcepath
If set, the source (.) builtin uses the value of PATH to find the directory
containing the file supplied as an argument. This option is enabled by DEFAULT.

xpg_echo
If set, the echo builtin expands backslash-escape sequences by DEFAULT.