Arithmetic Expansion below). If "\e[11~": "Function Key 1". in the results of pathname expansion. and tokenization (see, Expands to the names of variables whose names begin with. Background processes run in a separate process group and a line containing their exit status is printed upon their completion. promptvars: If set, prompt strings undergo parameter expansion, command substitution, arithmetic expansion, and quote removal after being expanded as described in "Prompting" above. regarded as a Arrays are assigned to using compound assignments of the form History expansion is performed immediately after a complete line is read, before the shell breaks it into words. List the possible completions of the text before point, treating it as a command name. Kill all characters on the current line, no matter where point is. -c: Specify the number of lines read between each call to callback. If the substring matches more than one job, When callback is evaluated, it is supplied the index of the next array element to be assigned and the line to be assigned to that element as additional arguments. See the "Invocation" section below for more details. A compound command is one of the following: When the == and != operators are used, the string to the This option is only used by interactive shells. -E: If set, any trap on ERR is inherited by shell functions, command substitutions, and commands executed in a subshell environment. If word evaluates to -, file descriptor n is closed. To strike with a heavy, crushing blow: The thug bashed the hood of the car with a sledgehammer. When used with [[, the < and > operators sort lexicographically using the current locale. Set to the line of input read by the read builtin command when no arguments are supplied. SHELL BUILTIN COMMANDS below). Various modifiers are available to manipulate the selected words. In the context where an assignment statement is assigning a value to a shell variable or array index, the += operator can be used to append to or add to the variable's previous value. redirections supplied to the, shell parameters that are set by variable assignment or with, shell functions defined during execution or inherited from the shell’s Cause shell-command to be executed whenever keyseq is entered. No filtering of the generated completions against the word being completed is performed; the function or command has complete freedom in generating the matches. >, the redirection refers to the standard output (file descriptor Display helpful information about builtin commands. Once a compspec has been found, it is used to generate the list of matching words. If the line consists of a number corresponding to one of the displayed words, then the value of name is set to that word. necessary, by removing the oldest entries, list. Specify how arguments to each name should be completed. In the following descriptions, point refers to the current cursor The command substitution $(cat file) can be replaced by A negative count searches for subsequent occurrences. The expanded value as the name of a file to read and execute. All values undergo tilde expansion, parameter and variable expansion, command substitution, arithmetic expansion, and quote removal (see the section "Expansion" below). the word is removed. If Alias with no arguments or with the -p option prints the list of aliases in the form alias name=value on standard output. The first backquote not preceded by a backslash terminates the The -v option causes the output to be assigned to the variable Redirection of input causes the file whose name results from the expansion of word to be opened for reading on file descriptor n, or the standard input (file descriptor 0) if n is not specified. The digits greater than 9 are represented by the lowercase letters, SIGHUP. Unless the reference is absolute, events are relative to the current position in the history list. Substrings matched by parenthesized subexpressions within the regular Fetch the previous command from the history list, moving back in the current one. Declare variables and/or give them attributes. <, the redirection refers to the standard input (file descriptor All builtins return an exit status of 2 to indicate incorrect usage. These timestamps are optionally displayed depending on the value of the HISTTIMEFORMAT variable. word to be opened for both reading and writing on file descriptor On startup, the history is initialized from the file named by Attempt completion on the text before point, treating it as a command name. local builtin commands. If no command name results, redirections are performed, but do not affect the current shell environment. HISTORY below), while the command number is the position in the sequence case do done elif else esac fi for function if in select then until while { } time [[ ]]. the command completes. If parameter is an array variable subscripted with @ or *, the case modification operation is applied to each member of the array in turn, and the expansion is the resultant list. Read-only variables cannot be reset. ‘, The number of commands to remember in the command history (see, If this variable is set and not null, its value is used as a format string name to a separate word. The following variables are used by the shell. Members of this process group (processes whose process group ID is equal to the current terminal process group ID) receive keyboard-generated signals such as SIGINT. |. @ have special meaning when in double affect the current shell environment. A value of ignoreboth is shorthand for ignorespace and ignoredups. If no jobspec is supplied, the -a option means to remove or mark all jobs; the -r option without a jobspec argument restricts operation to running jobs. getopts is silent, then a colon (:) is placed in Append the ‘‘new’’ history lines (history lines entered since the The value of BASH_ENV is subjected to parameter expansion, command substitution, and arithmetic expansion before being interpreted as a file name. The format for appending standard output and standard error is: This type of redirection instructs the shell to read input from the current source until a line containing only delimiter (with no trailing blanks) is seen. The FUNCNEST variable, if set to a numeric value greater than 0, defines a maximum function nesting level. Re-execute the last keyboard macro defined, by making the characters When a process is stopped, the shell immediately executes the next Generate possible completion matches for word according to the options, which may be any option accepted by the complete builtin with the exception of -p and -r, and write the matches to the standard output. The return status of a pipeline is the exit status of the last command, unless the pipefail option is enabled. If n specifies a non-existent process or job, the return status is 127. ~/.profile, in that order. This command is unbound by default. Accept the line regardless of where the cursor is. automatically have them defined with the When a compspec indicates that directory name completion is desired, greater than or equal to zero. set-mark command. This command is unbound by default. The second is to select portions of that line for inclusion into PATH is not used to search for the resultant file name. When invoked as an interactive login shell, or a non-interactive shell with the --login option, it first attempts to read and execute commands from /etc/profile and ~/.profile, in that order. the expansion of If a compspec has been defined for that command, the When The second character is the quick substitution character, which is used as shorthand for re-running the previous command entered, substituting one string for another in the command. To explicitly declare an array, use Positional parameters are assigned from the shell's arguments when it is invoked, and may be reassigned using the set builtin command. bash reports an error. An interactive shell without the interactive_comments option enabled does not allow comments. real user (group) id, and the -p option is not supplied, no startup The prompt is displayed only if input is coming from a terminal. To pathname expansion pattern globpat is expanded question mark characters may not in! 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