menu(4)

menu -- form description file for the menu command

Description

menu(1) is a menu and form generator that creates full-screen forms and menus for accepting user input and displaying information. The form or menu to be displayed is specified in a form description file that allows text, lists, input fields, contents of files, and output from commands to be displayed.

The form description file consists of a number of keywords, each denoting the start of a new section of the form. For example, there is a keyword .top which specifies that the text that follows will be placed at the top of the screen. The text in each section of the form description file can be hard-coded in the form description file, or it may be redirected from a file or command.

I/O redirection

In the form description file, text may be included from another file. This is handled by specifying a less than (<) character in the first column of the form description file, followed by the name of a file to include. The text included from the file will be included verbatim; that is, if the file contains keywords, they will not be processed, and no I/O redirection or command substitution will be performed on the input redirected from a file.

Command substitution

In the form description file, text may be the output from a shell command. This is handled by enclosing a command to be executed in backquotes. Note that no more than one command will be parsed per input line of the form description file, and no command may span more than one line of the form description file. Again, the text included from the output of the command will be included verbatim; that is, no keywords will be processed, and no I/O redirection or command substitution will be performed on the input given by the output of a command.

Comments

The form description file may contain comments, which will be ignored. Lines with a pound sign (#) in the first column are considered comments.

Keywords

This section describes all the keywords you can use in a form description file. The menu command is context-based: that is, it uses the set of keywords you have defined in the form description file (primarily the text following the .form keyword) to decide whether you have defined a form, a menu, or an information screen. There are no required keywords and there is no required order for keywords in a form description file. No keyword has a default value: if you do not define a keyword in a form description file, the element the keyword defines will not appear on the form, menu, or information screen.

.ul: specifies the contents of the banner at the upper left corner of the screen, in the title area. Used to display general information about the current menu (for example: System Installation).
.ur: specifies the contents of the banner at the upper right corner of the screen, in the title area. Used to display specific information about the current menu (for example: Load Floppy Disk).
.ll: specifies the contents of the banner at the lower left corner of the screen, in the help bar. Used to display specific information about the task at hand (for example: Enter A Value).
.lr: specifies the contents of the banner at the lower right corner of the screen in the help bar. Used to display special key information for the menu being displayed (for example: Del=Cancel F1=Help).
.top: specifies a block of text displayed above the form or menu area that describes the information being presented on the menu or form, or the information for an information screen.
.form: The menu, form, or information screen specification, used as described in the USAGE section.
.bottom: specifies a block of text displayed below the form or menu area that describes the actions to be taken on the menu or form, or more information for an information screen.
.help: specifies the help text that is presented when a user presses the 'F1' or '?' key (as described on the menu(1) manual page).
.helpinst: specifies the contents of the banner at the lower right corner of the screen in the help bar for a help screen. Used to display special key information for the help screen being displayed (for example: Esc=Quit help Del=Cancel F1=Instructions 1=Page down 2=Page up).
.hhelpinst: specifies the contents of the banner at the lower right corner of the screen in the help bar for the second-level help screen. Used to display special key information for the help screen being displayed (for example: Esc=Quit instructions Del=Cancel 1=Page down 2=Page up).
.working: specifies the text for the flashing message that is displayed in the help bar after a menu invoked with the -r option exits. For example, it can be used to display the word Working....
.helpbanner: this keyword is analogous to the .ul keyword, but for the help screen.
.hhelp_ban: this keyword is analogous to the .ul keyword, but for the second level help screen.
.pageno: specifies a format string for an sprintf(3S) statement, which is printed with two arguments, the current page number and the total number of pages.
This string is displayed at the top of a help screen: the specification would look like Page %d of %d. See fprintf(3S) for details.
.optstring: specifies the string displayed just above the items in a numbered menu. It is usually an introductory sentence or phrase, like Your options are:.
.selection: This is a format string for an sprintf(3S) statement, which is printed with two arguments, the first number choice for a numbered menu, and the total number of choices. This string is displayed below the last numbered item on the menu; the specification would look like Enter a number between %d and %d:. See fprintf(3S) for details.
.button: This section contains two strings; the first is the label for a radio button that applies the choices or changes the user has made in the menu or form (often the word Apply is used for this button), and the second is the label for a radio button that cancels the choices or changes the user has made in the menu or form (often the word Reset is used for this button). This keyword only defines the name that appears on the button, the function performed by each button is pre-defined and cannot be changed. This keyword is only useful on a form.
.end: This keyword is a null operator, and can be used to signal the end of a menu.

Usage

This section describes each of the three menu types, and what they are used for, what they look like, how to specify them in a form description file, and how a user navigates in and among them.

Numbered menus

A numbered menu is used to present a user with several choices in a situation where only one choice may be made. This is an example of a typical numbered menu:

What type of mouse is attached to your system?
1. Serial mouse
2. Bus mouse
3. PS/2-Compatible mouse
4. No mouse
Type a number between 1 and 4 followed by ENTER (or <Return>):_____

More can be defined in a numbered menu than is shown in this example, (see the complete list of keywords under ``Keywords'') but the following lines in a form description file would be sufficient to produce this menu:

   .optstring
   What type of mouse is attached to your system?
   .form
   Serial mouse
   Bus mouse
   PS/2-Compatible mouse
   No mouse
   .selection
   Type a number between %d and %d followed by ENTER (or <Return>):

The keyword .optstring causes the following line of text to be displayed one space above the numbered choices in the numbered menu. This is useful for an introduction to the list of choices, such as What type of mouse is attached to your system?.

The keyword .form, when followed by lines of plain text, causes each line following the keyword to be displayed as a numbered choice in the menu. The complete list is automatically followed by an input field.

The keyword .selection specifies a string that is displayed just below the last entry in a numbered menu, and just to the left of the input field that is displayed automatically following a numbered menu. The string following the .selection keyword is a format statement for an sprintf(3S) statement, and will accept two integers as arguments; the first number (always 1) and the last number of the items on the menu.

The user can exit a numbered menu in either of two ways; first, by interrupting the execution with a SIGINTR (for example, by pressing the DELETE key); and second, by entering a valid number in the input field. If the user enters an invalid number, or makes some other typing mistake, an error bar is displayed on the screen. The user can then erase the field with the backspace key and retype the value.

At exit from a numbered menu, the output file looks like this:

RETURN_VALUE="n``"''

where n is the number entered by the user.

Forms

A form is used for entering several pieces of related information on one screen or in situations requiring multiple decisions. For example, if menu were used to create a form to add a user to a system, it might look something like this:

First and last name: ______________________________
Login name: _________
ID number: _____
Home directory: ______________________________
+-------+ +-------+
| Apply | | Reset |
+-------+ +-------+

More can be defined in a form than is shown in this example, (see the complete list of keywords under ``Keywords'') but the following lines in a form description file would be sufficient to produce this form:

.form
5 0 30//[A-z0-9 ]*//First and last name://USERNAME//
//Enter the first and last name of the user being added//

5 0 8//[A-z0-9 ]*//Login name://LOGNAME//
//Enter the login name of the user being added (max 8 chars)//

1 3 100 1024//ID number://USERID//
//Enter the user ID of the user being added (100-1024)//

5 0 30//[A-z0-9/]*//Home directory://HOMEDIR//
//Enter the home directory of the user being added//

.button
Apply
Reset

Specifying a form is more complex than specifying a numbered menu. Each form field takes two lines in the form description file, in the format:

   field_type arg [arg ...]//string/string//...//ENVIRONMENT_VARIABLE//
   //More detailed instruction for field//

where field_type can be one of six types. The format for specifying each follows.

TYPE_ALPHA

This type of field is used to specify alphabetic input. The specification of this field would look like this in the form description file:

0 min max//ENVIRONMENT_VARIABLE
//Detailed description of what to enter//

Where min is the minimum length string to be accepted as input from the user, and max is the maximum length string to be accepted, and ENVIRONMENT_VARIABLE is the environment variable that will, in the output file, be assigned the value entered in this field.

TYPE_ALNUM

This type of field is used to specify alphanumeric input. The specification of this field would look like this in the form description file:

   1 min max//ENVIRONMENT_VARIABLE
   //Detailed description of what to enter//

TYPE_ENUM

This type of field is used to present an enumerated list of selections to the user which can be selected using the arrow keys. The specification of this field would look like this in the form description file:

   2 num//TAG::string1//...//TAG::stringnum
   //Field label//ENVIRONMENT_VARIABLE
   //Right/Left arrow keys for new choice (num choices)//

Where num is the number of choices to be enumerated for user selection in this field. For each of the num choices, there is a TAG::string pair, where the field will display string on the screen, and ENVIRONMENT_VARIABLE is the environment variable that will, in the output file, be assigned the TAG associated with the string selected in this field. TAG is a label associated with a string in a form that a shell script displaying a menu can use to make its decision. Thus, the shell script does not need to change if the string is translated to another language.

TYPE_INTEGER

This type of field is used to specify integer input. The specification of this field would look like this in the form description file:

   3 precision min max//ENVIRONMENT_VARIABLE
   //Detailed description of what to enter//

Where min is the minimum length string to be accepted as input from the user, and max is the maximum length string to be accepted, precision is the width for left padding with zeros, and ENVIRONMENT_VARIABLE is the environment variable that will, in the output file, be assigned the value entered in this field.

TYPE_NUMERIC

This type of field is used to specify numeric input. The specification of this field would look like this in the form description file:

   4 min max precision//ENVIRONMENT_VARIABLE
   //Detailed description of what to enter//

Where min is the minimum length string to be accepted as input from the user, and max is the maximum length string to be accepted, precision is the number of digits to the right of the decimal point, and ENVIRONMENT_VARIABLE is the environment variable that will, in the output file, be assigned the value entered in this field.

TYPE_REGEXP

This type of field is used to specify input that conforms to a regular expression. The specification of this field would look like this in the form description file:

   5 min max//regexp//ENVIRONMENT_VARIABLE
   //Detailed description of what to enter//

Where min is the minimum length string to be accepted as input from the user, and max is the maximum length string to be accepted, regexp is the ed(1) style regular expression to validate the input against, and ENVIRONMENT_VARIABLE is the environment variable that will, in the output file, be assigned the value entered in this field.

The keyword .button specifies the labels for the Radio Buttons at the bottom of the form. The text following this keyword should generally be the same as is shown the example, as the actions these buttons generate are to apply the current selection and move on, or to reset the form's fields to their values at invocation.

To navigate in a form, the user presses the TAB key to move to the next field or the BACKTAB (shifted TAB) key to move to the previous field. For all types of fields except the TYPE_ENUM type, the input field is shown in inverse-video, When the cursor is positioned in a field, the user can type a value in the inverse-video area. In TYPE_ENUM fields, the first choice is already displayed in the field, in bright video. The user can cause the next choice to be displayed in the field. by pressing the left or right arrow key (or the '-' or '+' keys). The user can select the choice currently displayed, and move on to the next field, by pressing ENTER or TAB.

When the form is filled out to the user's satisfaction, the user then presses the TAB key to move to the Apply Radio Button, and presses ENTER to apply the choices filled out in the form fields. A user cannot exit from a form screen until the Apply button is ``pressed'' (or menu is interrupted).

After the form has been filled out, a user can reset the form to its state when first displayed by pressing the TAB key to move to the Reset Radio Button, and then pressing ENTER.

Information screens

An information screen is used to display copyright notices, warning messages, or other information. In an information screen the user does not need to enter any data, but does need to acknowledge seeing the screen before moving on. After the information that is displayed, the rest of the form may look like this:

   Press ENTER (or <Return>) to continue: _

More can be defined in an information screen than is shown in this example, (see the complete list of keywords under ``Keywords'') but the following lines in a form description file would be sufficient to produce this information screen:

.selection


 Press ENTER (or <Return>) to continue:




 .form


 ENTER

If a .form section is specified and just contains the string ENTER, then the string specified in the section delineated by the .selection keyword is displayed near the bottom of the screen, and the cursor is placed to the right of that string.

If no .form section is specified, then the behavior will be similar, that is, the user must press ENTER or <Return> to exit the menu tool (or interrupt its execution). The only difference is that if no .form section is specified and the -r command-line option is specified, then menu exits (it does not wait for input from the user), the "Working..." message flashes at the bottom of the screen, and the screen is not cleared. This would typically be used, for instance, to announce something that is going to take some processing time (such as a kernel rebuild), where the user does not need to press any key to start the processing.

Examples

Numbered menus

The following is an example of a numbered menu and its Help Screen, followed by the contents of the form description file that generated it.

   |----------------------------------------------------------|
   |Operating System Installation    Foundation Set Media Type|
   |----------------------------------------------------------|
   |                                                          |
   |Software for this operating system is packaged in sets.   |
   |The Foundation Set is the required software all users     |
   |must install.  Read the help screen for more information. |
   |Select the distribution format and drive you will be      |
   |using to install the Foundation Set.                      |
   |                                                          |
   |                                                          |
   |Your choices are:                                         |
   |       1.  Floppy Drive 1                                 |
   |       2.  Floppy Drive 2                                 |
   |       3.  Cartridge Tape                                 |
   |                                                          |
   |Type a number from '1' to '3' followed by ENTER/RETURN: __|
   |                                                          |
   |----------------------------------------------------------|
   |Please make a selection        |Del=Cancel  F1=Help       |
   |----------------------------------------------------------|

The following help screen would be displayed when a user presses F1.

   |----------------------------------------------------------|
   |Help on Foundation Set Media Type       Page 1 of 1       |
   |----------------------------------------------------------|
   |                                                          |
   |For further instructions on using this help facility and  |
   |on using the installation program, press the 'F1' key (or |
   |the '?' key) at any time while you are reading help.      |
   |                                                          |
   |If you need more information than is available through    |
   |this help facility, refer to the "Installation Guide".    |
   |                                                          |
   |The Installation Process needs to know where to look for  |
   |the software that needs to be installed.                  |
   |----------------------------------------------------------|
   | | Del=Cancel  F1=Help  ESC=Exit help  1=Forward  2=Back  |
   |----------------------------------------------------------|

The following listing is the source file for this menu and its help screen.

.pageno Page %d of %d .ul Operating System Installation .hhelp_ban Help on the Help facility and the Installation program .helpbanner Help on Foundation Set Media Type .ur Foundation Set Media Type .ll Please make a selection. .lr Del=Cancel F1=Help .top Software for the Operating System is packaged in sets. The Foundation Set is the required software all users must install.

Select the distribution format and drive you will be using to install the Foundation Set. .optstring Your choices are: .form `[ "${NF1}" = "1" ] && echo "Floppy Drive 1"` `[ "${NF2}" = "1" ] && echo "Floppy Drive 2"` `[ "${NC1}" = "1" ] && echo "Cartridge Tape"` .selection Press a number between %d and %d followed by ENTER/RETURN: .help For further instructions on using this help facility and on using the installation program, press the 'F1' key (or the '?' key) at any time while you are reading help.

If you need more information than is available through this help facility, refer to the "Installation Guide".

The Installation Process needs to know where to look for the software that needs to be installed. .helpinst Del=Cancel F1=Help ESC=Exit help 1=Forward 2=Back .working Working... .end

Forms

The following is an example of a multiple-field form followed by the contents of the form description file that generated it. (The help portion of a form is specified in the same way as it is for a menu; it is not repeated in this example.)

   |----------------------------------------------------------|
   |Operating System Installation     Owner's Account         |
   |----------------------------------------------------------|
   |                                                          |
   |Create a login account for your use in accessing the      |
   |computer.  Read the Help screen for information about     |
   |each field.                                               |
   |                                                          |
   |               Owner's name:  _________________________   |
   |         Owner's login name:  ________                    |
   |        Owner's user number:  _____                       |
   |Owner's desktop environment:  _________                   |
   |                                                          |
   |                            +-----+       +-----+         |
   |                            |Apply|       |Reset|         |
   |                            +-----+       +-----+         |
   |                                                          |
   |Press 'TAB' to move the cursor between fields.  When      |
   |finished, move the cursor to "Apply" and then press       |
   |'ENTER' (or '<Return>') to continue.                        |
   |----------------------------------------------------------|
   |Type the owner's first and last name  |Del=Cancel  F1=Help|
   |----------------------------------------------------------|

The following listing is the source file for this form.

.pageno Page %d of %d .ul Operating System Installation .hhelp_ban Help on Help and How to Use the Menu Tool .helpbanner Help on Owner's Account .ur Owner's Account .ll .lr Del=Cancel F1=Help .top < /tmp/err.login

Create a login account for your use in accessing the computer. Read the Help screen for information about each field.

.form 5 3 25//[^:]+//Owner's name://USERNAME// //Type the owner's first and last name//
1 2 8 //Owner's login name://USERID// //Type the owner's login name// 5 1 5//[0-9]+//Owner's user number://USERNUM// //Type the owner's user number (must be 101 or higher)// `[ "${DESKTOP_PRESENT}" = "Yes" ] && echo "2 3//OLOOK::OPEN_LOOK (tm)//MOTIF:\ :Motif//NONE::None//Owner's desktop environment://DESKTOP// "` `[ "${DESKTOP_PRESENT}" = "Yes" ] && echo "//Right/Left arrow keys for\ more choices// "` .button Apply Reset .bottom Press 'TAB' to move the cursor between fields. When finished, move the cursor to "Apply" and then press 'ENTER' (or '<Return>') to continue.

. . help screens could be defined here .

.working Working... .end

Information screens

The following is an example of a "Press Enter to Continue" menu followed by the contents of the form description file that generated it. (The help portion of an information screen is specified in the same way as it is for a menu, thus it is indicated here by ellipses.)

   |----------------------------------------------------------|
   |Foundation Set Installation        Installation Complete  |
   |----------------------------------------------------------|
   |                                                          |
   |The Foundation Set installation is complete.  Applications|
   |and other software sets can be installed using the tools  |
   |available with the Foundation Set.                        |
   |                                                          |
   |After the computer reboots you will see a login prompt.   |
   |Type a login, either "root" to do system maintenance,     |
   |or the user account login created in the previous step.   |
   |                                                          |
   |Please refer to the "Getting Started Manual" for more     |
   |information.                                              |
   |                                                          |
   |                                                          |
   |Press 'Enter' (or '<Return>') to continue: _____            |
   |----------------------------------------------------------|
   |                                     |Del=Cancel  F1=Help |
   |----------------------------------------------------------|

The following listing is the source file for this information screen.

.pageno Page %d of %d .ul Foundation Set Installation .hhelp_ban Help on the Help facility and the Installation program .helpbanner Help on Installation Complete .ur Installation Complete .ll .lr Del=Cancel F1=Help .top The Foundation Set installation is complete. Applications and other software sets can be installed using the tools available with the Foundation Set.

After the computer reboots you will see a login prompt. Type a login, either "root" to do system maintenance, or the user account login you created in the previous step.

Please refer to the "Getting Started Manual" for more information. .form ENTER .selection Press 'ENTER' (or '<Return>') to continue:

. . help screens could be defined here .

.working Working... .end

References

menu(1), menu_colors.sh(1)

Notices

menu(4) will be made obsolete and be replaced with other tools in future releases.