V8/usr/man/man9/menuhit.9

.TH MENUHIT 9.3
.SH NAME
menuhit \- present user with menu and get selection
.SH SYNOPSIS
.B #include <jerq.h>
.PP
.B int menuhit(m, n)
.br
.B Menu *m; int n;
.SH DESCRIPTION
.I Menuhit
presents the user with a menu specified by the Menu pointer
.I m
and returns an integer indicating the selection made,
or
\-1
for no selection.
The integer
.I n
specifies which button to use for the interaction: 1, 2 or 3.
.I Menuhit
assumes that the button is already depressed when it is called.
The user makes a selection by lifting the button when the cursor
points at the desired selection;
lifting the button outside the menu indicates no selection.
.PP
Menus can be built in two ways, either as an array of
strings or with a generator function:
.nf
.IP
char *menutext[]={"Item 0", "Item 1", "Item 2", 0};
Menu stringsmenu={ menutext };
.PP
or
.IP
char *menugen();
Menu genmenu={ (char **)0, menugen };
.fi
.PP
The generator function is passed an integer parameter
.IR n ,
and must return the string for the
.IR n 'th
menu entry, or 0 if
.I n
is beyond the number of entries in the menu.
.PP
Regardless of the method of generation, characters with the 0200 bit
set are regarded as fill characters.
For example, the string "\e240X" will appear in the menu as a right-justified X.
Menu strings without fill characters are drawn centered in the menu. 
.PP
Here is an example, using the list-of-strings
.I menu
defined above:
.nf
.IP
switch(menuhit(&stringsmenu, 3)){	/* Use right button */
	case 0:
		item_0();
		break;
	case 1:
		item_1();
		break;
	case 2:
		item_2();
		break;
	case \-1:
		noselection();
		break;
}
.fi
.PP