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prompt(1) [posix man page]

PROMPT(1)																 PROMPT(1)

prompt - give any program command-line editing facilities SYNOPSIS
prompt is a simple wrapper which provides command-line editing for programs that do not have it. Not all programs with a command line interface provide an input history or even the ability to use the cursor keys to change the input. The prompt program wraps any program, intercepting stdin, stdout and stderr and providing the user with such editing facilities. SEE ALSO
modglue(1). ptywrap(1). See the web page at for more information. AUTHORS
Kasper Peeters <> Jul 12, 2008 PROMPT(1)

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ied(1)							      General Commands Manual							    ied(1)

ied - input editor and command history for interactive programs SYNOPSIS
file] charmap] prompt] size] utility [arguments]... DESCRIPTION
The utility command is intended to act as an interface between the user and an interactive program such as or a shell, providing most of the line editing and history functionality found in the Korn shell. interprets the utility name as the command to be executed, and passes arguments as the arguments to the utility. Subsequent input to utility then has access to editing and history functions very similar to those provided by monitors the state of the pty it uses to run the command; whenever the application it is running changes the state from the state of the tty when started, becomes "transparent". This allows programs to do shell escapes to screen-smart programs. In general, should not in any way interfere with any action taken by any program for which it provides a front end. This includes Korn shell itself: in this case would provide history for any application that was run by and would provide its own independent history. In a useful extreme case, can be used as a front end to the login shell (which might be or In this case, all applications that use normal line editing gain line editing and his- tory, sharing a single history. The shell would continue to have its own independent history if it provides such a mechanism. When is in its transparent mode, no history is saved. In particular the mode of does not use normal line editing (rather, it simulates it) and cannot provide history in this case. The and address line editing of mailx also cannot be edited with Options Several options and command-line arguments control operation: Debug mode. Print information about the operation of the program. It is best used to determine if a program puts into transpar- ent mode unexpectedly. Keep the history in a file named filename. If a file of that name already exists and is a history file, the latter part of it (the last size lines as specified by the option) is used as the initial value of the history. If the option is not used, the environment variable is used to supply the name. If neither is present, an unnamed temporary file is used, and no initial value is provided. Force interactive mode. Normally simply the command to which it is asked to be a front end when the standard input is not a tty (this allows aliases to be used for commands used in shells without interfering with their operation). This option forces to remain as a front end, and all editing functions are in place. This permits a utility that behaves differently in interactive and batch modes to be driven from a pipe or file in interactive mode. This is particularly useful in testing commands that make this distinction. charmap is a file of 256 or fewer lines. The line number in the file is the ordinal of a character as seen as input by and the character on the line is the character generated as output (and also used as editing characters). This allows remapping of (ordinary) keys such as for a Dvorak keyboard. Characters must start in column one of each line, and be represented as 1-4 characters followed by a space or the newline character for the next line. Characters after the space are ignored as comments. Single-character entries represent themselves. Two-character entries where the first character is a circumflex converts the second character to the corresponding control character. Two-character sequences where the first character is backslash use the C language conventions: newline s space \ escape null return f form feed tab v vertical tab  backspace Three- and four-character sequences must be or giving the octal value for the character. If charmap is less than 256 lines long, the remaining characters are mapped to themselves. Many commands do not prompt when ready for input. approximates a prompting mechanism for such commands. This is not always perfectly successful, but for many commands it helps. In the worst case, the prompt is interspersed with output in the wrong location. prompt is a string as used in the format argument to (see printf(3S)). The only conversions that can be included are up to one instance of which is converted to the sequential number of the command, and any number of occurrences of which is treated as a literal character. Prompting is suppressed when is operating in transparent mode. This sets "non-raw" mode. Normally uses its own editing capabilities when reading simple text. This causes to use tty line discipline most of the time. The disadvantage of the default mode is that more context switches and general processing are required. The advantage is that is more transparent. For example, to specifically send an end-of-file in the non-raw mode requires that the end-of-file character (usually Ctrl-D) be followed by a carriage return. Similarly the "literal next" function (Ctrl-V) cannot escape the line-erase and line-kill functions in non-raw mode. This option specifies the size of the history buffer. When is started with an existing history file, approximately the last size lines are available to the history mecha- nism (the number is not guaranteed to be exactly size). Other lines in the file are retained until such time as is started on that history file and it exceeds approximately 4K bytes in size, at which time discards older entries at the beginning of the file until it is near 4 KB in size. Since this occurs only at startup, history files can grow to be quite large between restarts. Larger values of size make the process image larger. If is not specified, the value of the environment variable is used. If neither is specified, a default is used. Set transparent mode. This forces to permanently be in transparent mode (as discussed above). It is primarily useful with for some classes of automated processing. In particular, it is useful for driving a command if the command takes as input what would interpret as editing characters. Thus with the appropriate combinations of and it is possible to drive an editor such as or a screen-smart application from a batch file. Should something go wrong with the signal, repeated 3 times, usually aborts The exception is the case of a fully transparent application, where must be killed from another window or terminal. This is really relevant only when there is no way to direct the serviced process to terminate itself. The editing capabilities of are essentially those found in Only those that differ from are described below. As in the style of editing is determined from the environment variable or from if is not specified. The value examined should end in or to specify an editor type. If it does not, does no editing, and history is not accessible. In mode: Join lines. Considering the most recently edited line (which is empty immediately after a line is sent to the application) to be the "last line" of the history, the current line being displayed from the history is appended to the end of the last line, and the position in the history is reset to be at the last line which is then displayed. A space is inserted between the old and new text on the last line. The cursor is left on that space. Because understanding of line con- tinuation is minimal, this is useful for editing long statements. Not supported. Not supported. Sends nothing to the application, but inserts the line in the history (useful for adding comments to history file). (File name expansion). Not supported. Macro expansion. Not supported. Note however that has a rarely-used function that substitutes words from the previous line (this is not the macro but rather an editor command). If a preceding count is given, it uses the countth word of the last line. This is much more useful with In mode: (file name expansion) Not supported. Note that the command (and its synonym provide the same functionality as the mode command. Macro expansion. Not supported. Although supported, it may not always appear correctly on the screen. The command can be used to redraw the line. See below for the discussion on prompting. EXAMPLES
Add interactive editing to the command: Execute on using comands taken from Note that, without the use of would misbehave because its standard input would not be a terminal device. In this case, the is not required because puts itself in raw mode, but for an application that does not, might be required. The command line searches the file for lines beginning with sending one copy to the terminal and a second to file just like the command line The difference is that in the command line without writes directly to a pipe, and thus buffers its output. If is very large and not many lines match the pattern, output to the terminal is delayed. By using the output of goes to a pty instead, which causes to output each line as it is ready. WARNINGS
Since cannot know everything about every application, it is possible that it can become confused, with either the timing or the prompt being out of phase with the application. Since the use of is never required, it is the user's choice to determine whether the application is more usable with or without In general, however, programs that do not confuse are usually also the most likely to benefit from its use. tries to intuit the currently active prompt when it is not providing one itself. However, this is not always successful. Even when it is successful, the timing of and the serviced command may occasionally confuse the output. The commands in both and modes redraw the edit line in a consistent fashion that can be used to create the next command. AUTHOR
was developed by HP. SEE ALSO
bc(1), bs(1), csh(1), ex(1), grep(1), ksh(1), vi(1), printf(3S). ied(1)
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