The return value is 0 unless an unrecognized option is given or an error occurred.
Using `+' instead of `-' turns off the attribute instead. When used in a function, makes names local, as with the local command. The return value is 0 unless an illegal option is encountered, an attempt is made to define a function using "-f foo=bar", one of the names is not a legal shell variable name, an attempt is made to turn off readonly status for a readonly variable, or an attempt is made to display a non-existant function with -f.
The return value is 0 unless an illegal option is supplied or n indexes beyond the end of the directory stack.
The -n flag suppresses the command numbers when listing. The -r flag reverses the order of the commands. If the -l flag is given, the commands are listed on standard output. Otherwise, the editor given by ename is invoked on a file containing those commands. If ename is not given, the value of the FCEDIT variable is used, and the value of EDITOR if FCEDIT is not set. If neither variable is set, is used. When editing is complete, the edited commands are echoed and executed.
In the second form, command is re-executed after each instance of pat is replaced by rep. 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.
If the first form is used, the return value is 0 unless an illegal option is encountered or first or last specify history lines out of range. If the -e option is supplied, the return value is the value of the last command executed or failure if an error occurs with the temporary file of commands. If the second form is used, the return status is that of the command re-executed, unless cmd does not specify a valid history line, in which case fc returns failure.
getopts can report errors in two ways. If the first character of optstring is a colon, silent error reporting is used. In normal operation diagnostic messages are printed when illegal options or missing option arguments are encountered. If the variable OPTERR is set to 0, no error message will be displayed, even if the first character of optstring is not a colon.
If an illegal option is seen, getopts places ? into name and, if not silent, prints an error message and unsets OPTARG. If getopts is silent, the option character found is placed in OPTARG and no diagnostic message is printed.
If a required argument is not found, and getopts is not silent, a question mark (?) is placed in name, OPTARG is unset, and a diagnostic message is printed. If getopts is silent, then a colon (:) is placed in name and OPTARG is set to the option character found.
getopts normally parses the positional parameters, but if more arguments are given in args, getopts parses those instead. getopts returns true if an option, specified or unspecified, is found. It returns false if the end of options is encountered or an error occurs.
The return value is 0 unless an illegal option is encountered or an error occurs while reading or writing the history file.
If the -x option is supplied, jobs replaces any jobspec found in command or args with the corresponding process group ID, and executes command passing it args, returning its exit status.
If the popd command is successful, a dirs is performed as well, and the return status is 0. popd returns false if an illegal option is encountered, the directory stack is empty, a non-existent directory stack entry is specified, or the directory change fails.
If the pushd command is successful, a dirs is performed as well. If the first form is used, pushd returns 0 unless the cd to dir fails. With the second form, pushd returns 0 unless the directory stack is empty, a non-existant directory stack element is specified, or the directory change to the specified new current directory fails.
If no option-name is supplied, the values of the current options are printed.
The flags are off by default unless otherwise noted. Using + rather than - causes these flags to be turned off. The flags can also be specified as options to an invocation of the shell. The current set of flags may be found in $-. After the option arguments are processed, the remaining n args are treated as values for the positional parameters and are assigned, in order, to $1, $2, ... $n. If no options or args are supplied, all shell variables are printed. The return status is always true unless an illegal option is encountered.
An argument of -- disables option checking for the rest of the arguments. If limit is given, it is the new value of the specified resource (the -a option is display only). If no option is given, then -f is assumed. Values are in 1024-byte increments, except for -t, which is in seconds, -p, which is in units of 512-byte blocks, and -n and -u, which are unscaled values. The return status is 0 unless an illegal option is encountered, a non-numeric argument other than unlimited is supplied as limit, or an error occurs while setting a new limit.
Created by unroff & hp-tools. © by Hans-Peter Bischof. All Rights Reserved (1997).
Last modified 21/April/97