Translations by Pekka Niemi

for (( exp1; exp2; exp3 )); do COMMANDS; done

select NAME [in WORDS ... ;] do COMMANDS; done

time [-p] pipeline

case WORD in [PATTERN [| PATTERN]...) COMMANDS ;;]... esac

if COMMANDS; then COMMANDS; [ elif COMMANDS; then COMMANDS; ]... [ else COMMANDS; ] fi

while COMMANDS; do COMMANDS; done

until COMMANDS; do COMMANDS; done

coproc [NAME] command [redirections]

function name { COMMANDS ; } or name () { COMMANDS ; }

{ COMMANDS ; }

job_spec [&]

(( expression ))

[[ expression ]]

variables - Names and meanings of some shell variables

pushd [-n] [+N | -N | dir]

popd [-n] [+N | -N]

dirs [-clpv] [+N] [-N]

shopt [-pqsu] [-o] [optname ...]

printf [-v var] format [arguments]

readarray [-n count] [-O origin] [-s count] [-t] [-u fd] [-C callback] [-c quantum] [array]

Exit for, while, or until loops. Exit a FOR, WHILE or UNTIL loop. If N is specified, break N enclosing loops. Exit Status: The exit status is 0 unless N is not greater than or equal to 1.

Resume for, while, or until loops. Resumes the next iteration of the enclosing FOR, WHILE or UNTIL loop. If N is specified, resumes the Nth enclosing loop. Exit Status: The exit status is 0 unless N is not greater than or equal to 1.

Execute shell builtins. Execute SHELL-BUILTIN with arguments ARGs without performing command lookup. This is useful when you wish to reimplement a shell builtin as a shell function, but need to execute the builtin within the function. Exit Status: Returns the exit status of SHELL-BUILTIN, or false if SHELL-BUILTIN is not a shell builtin..

Return the context of the current subroutine call. Without EXPR, returns "$line $filename". With EXPR, returns "$line $subroutine $filename"; this extra information can be used to provide a stack trace. The value of EXPR indicates how many call frames to go back before the current one; the top frame is frame 0. Exit Status: Returns 0 unless the shell is not executing a shell function or EXPR is invalid.

Null command. No effect; the command does nothing. Exit Status: Always succeeds.

Return a successful result. Exit Status: Always succeeds.

Return an unsuccessful result. Exit Status: Always fails.

Write arguments to the standard output. Display the ARGs on the standard output followed by a newline. Options: -n do not append a newline Exit Status: Returns success unless a write error occurs.

Enable and disable shell builtins. Enables and disables builtin shell commands. Disabling allows you to execute a disk command which has the same name as a shell builtin without using a full pathname. Options: -a print a list of builtins showing whether or not each is enabled -n disable each NAME or display a list of disabled builtins -p print the list of builtins in a reusable format -s print only the names of Posix `special' builtins Options controlling dynamic loading: -f Load builtin NAME from shared object FILENAME -d Remove a builtin loaded with -f Without options, each NAME is enabled. To use the `test' found in $PATH instead of the shell builtin version, type `enable -n test'. Exit Status: Returns success unless NAME is not a shell builtin or an error occurs.

Execute arguments as a shell command. Combine ARGs into a single string, use the result as input to the shell, and execute the resulting commands. Exit Status: Returns exit status of command or success if command is null.

Parse option arguments. Getopts is used by shell procedures to parse positional parameters as options. OPTSTRING contains the option letters to be recognized; if a letter is followed by a colon, the option is expected to have an argument, which should be separated from it by white space. Each time it is invoked, getopts will place the next option in the shell variable $name, initializing name if it does not exist, and the index of the next argument to be processed into the shell variable OPTIND. OPTIND is initialized to 1 each time the shell or a shell script is invoked. When an option requires an argument, getopts places that argument into the shell variable OPTARG. getopts reports errors in one of two ways. If the first character of OPTSTRING is a colon, getopts uses silent error reporting. In this mode, no error messages are printed. If an invalid option is seen, getopts places the option character found into OPTARG. If a required argument is not found, getopts places a ':' into NAME and sets OPTARG to the option character found. If getopts is not in silent mode, and an invalid option is seen, getopts places '?' into NAME and unsets OPTARG. If a required argument is not found, a '?' is placed in NAME, OPTARG is unset, and a diagnostic message is printed. If the shell variable OPTERR has the value 0, getopts disables the printing of error messages, even if the first character of OPTSTRING is not a colon. OPTERR has the value 1 by default. Getopts normally parses the positional parameters ($0 - $9), but if more arguments are given, they are parsed instead. Exit Status: Returns success if an option is found; fails if the end of options is encountered or an error occurs.

Exit the shell. Exits the shell with a status of N. If N is omitted, the exit status is that of the last command executed.

Exit a login shell. Exits a login shell with exit status N. Returns an error if not executed in a login shell.

Display or execute commands from the history list. fc is used to list or edit and re-execute commands from the history list. FIRST and LAST can be numbers specifying the range, or FIRST can be a string, which means the most recent command beginning with that string. Options: -e ENAME select which editor to use. Default is FCEDIT, then EDITOR, then vi -l list lines instead of editing -n omit line numbers when listing -r reverse the order of the lines (newest listed first) With the `fc -s [pat=rep ...] [command]' format, COMMAND is re-executed after the substitution OLD=NEW is performed. A useful alias to use with this is r='fc -s', so that typing `r cc' runs the last command beginning with `cc' and typing `r' re-executes the last command. Exit Status: Returns success or status of executed command; non-zero if an error occurs.

Move job to the foreground. Place the job identified by JOB_SPEC in the foreground, making it the current job. If JOB_SPEC is not present, the shell's notion of the current job is used. Exit Status: Status of command placed in foreground, or failure if an error occurs.

Move jobs to the background. Place the jobs identified by each JOB_SPEC in the background, as if they had been started with `&'. If JOB_SPEC is not present, the shell's notion of the current job is used. Exit Status: Returns success unless job control is not enabled or an error occurs.

Return from a shell function. Causes a function or sourced script to exit with the return value specified by N. If N is omitted, the return status is that of the last command executed within the function or script. Exit Status: Returns N, or failure if the shell is not executing a function or script.

Set export attribute for shell variables. Marks each NAME for automatic export to the environment of subsequently executed commands. If VALUE is supplied, assign VALUE before exporting. Options: -f refer to shell functions -n remove the export property from each NAME -p display a list of all exported variables and functions An argument of `--' disables further option processing. Exit Status: Returns success unless an invalid option is given or NAME is invalid.

Shift positional parameters. Rename the positional parameters $N+1,$N+2 ... to $1,$2 ... If N is not given, it is assumed to be 1. Exit Status: Returns success unless N is negative or greater than $#.

Execute commands from a file in the current shell. Read and execute commands from FILENAME in the current shell. The entries in $PATH are used to find the directory containing FILENAME. If any ARGUMENTS are supplied, they become the positional parameters when FILENAME is executed. Exit Status: Returns the status of the last command executed in FILENAME; fails if FILENAME cannot be read.

Suspend shell execution. Suspend the execution of this shell until it receives a SIGCONT signal. Unless forced, login shells cannot be suspended. Options: -f force the suspend, even if the shell is a login shell Exit Status: Returns success unless job control is not enabled or an error occurs.

Evaluate conditional expression. This is a synonym for the "test" builtin, but the last argument must be a literal `]', to match the opening `['.

Display process times. Prints the accumulated user and system times for the shell and all of its child processes. Exit Status: Always succeeds.

Display or set file mode mask. Sets the user file-creation mask to MODE. If MODE is omitted, prints the current value of the mask. If MODE begins with a digit, it is interpreted as an octal number; otherwise it is a symbolic mode string like that accepted by chmod(1). Options: -p if MODE is omitted, output in a form that may be reused as input -S makes the output symbolic; otherwise an octal number is output Exit Status: Returns success unless MODE is invalid or an invalid option is given.

Execute commands for each member in a list. The `for' loop executes a sequence of commands for each member in a list of items. If `in WORDS ...;' is not present, then `in "$@"' is assumed. For each element in WORDS, NAME is set to that element, and the COMMANDS are executed. Exit Status: Returns the status of the last command executed.

Arithmetic for loop. Equivalent to (( EXP1 )) while (( EXP2 )); do COMMANDS (( EXP3 )) done EXP1, EXP2, and EXP3 are arithmetic expressions. If any expression is omitted, it behaves as if it evaluates to 1. Exit Status: Returns the status of the last command executed.

Select words from a list and execute commands. The WORDS are expanded, generating a list of words. The set of expanded words is printed on the standard error, each preceded by a number. If `in WORDS' is not present, `in "$@"' is assumed. The PS3 prompt is then displayed and a line read from the standard input. If the line consists of the number corresponding to one of the displayed words, then NAME is set to that word. If the line is empty, WORDS and the prompt are redisplayed. If EOF is read, the command completes. Any other value read causes NAME to be set to null. The line read is saved in the variable REPLY. COMMANDS are executed after each selection until a break command is executed. Exit Status: Returns the status of the last command executed.

Report time consumed by pipeline's execution. Execute PIPELINE and print a summary of the real time, user CPU time, and system CPU time spent executing PIPELINE when it terminates. Options: -p print the timing summary in the portable Posix format The value of the TIMEFORMAT variable is used as the output format. Exit Status: The return status is the return status of PIPELINE.

Execute commands based on pattern matching. Selectively execute COMMANDS based upon WORD matching PATTERN. The `|' is used to separate multiple patterns. Exit Status: Returns the status of the last command executed.

Execute commands based on conditional. The `if COMMANDS' list is executed. If its exit status is zero, then the `then COMMANDS' list is executed. Otherwise, each `elif COMMANDS' list is executed in turn, and if its exit status is zero, the corresponding `then COMMANDS' list is executed and the if command completes. Otherwise, the `else COMMANDS' list is executed, if present. The exit status of the entire construct is the exit status of the last command executed, or zero if no condition tested true. Exit Status: Returns the status of the last command executed.