1menu_driver(3X) menu_driver(3X)
2
6 menu_driver - command-processing loop of the menu system
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9 #include <menu.h>
10 int menu_driver(MENU *menu, int c);
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13 Once a menu has been posted (displayed), you should funnel input events
14 to it through menu_driver. This routine has three major input cases:
15 · The input is a form navigation request. Navigation request codes
17 are constants defined in <form.h>, which are distinct from the key-
18 and character codes returned by wgetch.
19 · The input is a printable character. Printable characters (which
21 must be positive, less than 256) are checked according to the pro‐
22 gram's locale settings.
23 · The input is the KEY_MOUSE special key associated with an mouse
25 event.
26 The menu driver requests are as follows:
28 REQ_LEFT_ITEM
30 Move left to an item.
31 REQ_RIGHT_ITEM
33 Move right to an item.
34 REQ_UP_ITEM
36 Move up to an item.
37 REQ_DOWN_ITEM
39 Move down to an item.
40 REQ_SCR_ULINE
42 Scroll up a line.
43 REQ_SCR_DLINE
45 Scroll down a line.
46 REQ_SCR_DPAGE
48 Scroll down a page.
49 REQ_SCR_UPAGE
51 Scroll up a page.
52 REQ_FIRST_ITEM
54 Move to the first item.
55 REQ_LAST_ITEM
57 Move to the last item.
58 REQ_NEXT_ITEM
60 Move to the next item.
61 REQ_PREV_ITEM
63 Move to the previous item.
64 REQ_TOGGLE_ITEM
66 Select/deselect an item.
67 REQ_CLEAR_PATTERN
69 Clear the menu pattern buffer.
70 REQ_BACK_PATTERN
72 Delete the previous character from the pattern buffer.
73 REQ_NEXT_MATCH
75 Move to the next item matching the pattern match.
76 REQ_PREV_MATCH
78 Move to the previous item matching the pattern match.
79 If the second argument is a printable character, the code appends it to
81 the pattern buffer and attempts to move to the next item matching the
82 new pattern. If there is no such match, menu_driver returns E_NO_MATCH
83 and deletes the appended character from the buffer.
84 If the second argument is one of the above pre-defined requests, the
86 corresponding action is performed.
87 MOUSE HANDLING
89 If the second argument is the KEY_MOUSE special key, the associated
90 mouse event is translated into one of the above pre-defined requests.
91 Currently only clicks in the user window (e.g., inside the menu display
92 area or the decoration window) are handled.
93 If you click above the display region of the menu:
95 · a REQ_SCR_ULINE is generated for a single click,
97 · a REQ_SCR_UPAGE is generated for a double-click and
99 · a REQ_FIRST_ITEM is generated for a triple-click.
101 If you click below the display region of the menu:
103 · a REQ_SCR_DLINE is generated for a single click,
105 · a REQ_SCR_DPAGE is generated for a double-click and
107 · a REQ_LAST_ITEM is generated for a triple-click.
109 If you click at an item inside the display area of the menu:
111 · the menu cursor is positioned to that item.
113 · If you double-click an item a REQ_TOGGLE_ITEM is generated and
115 E_UNKNOWN_COMMAND is returned. This return value makes sense,
116 because a double click usually means that an item-specific action
117 should be returned. It is exactly the purpose of this return value
118 to signal that an application specific command should be executed.
119 · If a translation into a request was done, menu_driver returns the
121 result of this request.
122 If you clicked outside the user window or the mouse event could not be
124 translated into a menu request an E_REQUEST_DENIED is returned.
125 APPLICATION-DEFINED COMMANDS
127 If the second argument is neither printable nor one of the above pre-
128 defined menu requests or KEY_MOUSE, the drive assumes it is an applica‐
129 tion-specific command and returns E_UNKNOWN_COMMAND. Application-
130 defined commands should be defined relative to MAX_COMMAND, the maximum
131 value of these pre-defined requests.
132
134 menu_driver return one of the following error codes:
135 E_OK The routine succeeded.
137 E_SYSTEM_ERROR
139 System error occurred (see errno).
140 E_BAD_ARGUMENT
142 Routine detected an incorrect or out-of-range argument.
143 E_BAD_STATE
145 Routine was called from an initialization or termination function.
146 E_NOT_POSTED
148 The menu has not been posted.
149 E_UNKNOWN_COMMAND
151 The menu driver code saw an unknown request code.
152 E_NO_MATCH
154 Character failed to match.
155 E_REQUEST_DENIED
157 The menu driver could not process the request.
158
160 curses(3X), menu(3X), getch(3X).
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163 The header file <menu.h> automatically includes the header files
164 <curses.h>.
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167 These routines emulate the System V menu library. They were not sup‐
168 ported on Version 7 or BSD versions. The support for mouse events is
169 ncurses specific.
170
172 Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S.
173 Raymond.
174 menu_driver(3X)