1form_driver(3X) form_driver(3X)
2
6 form_driver, form_driver_w - command-processing loop of the form system
7
9 #include <form.h>
10 int form_driver(FORM *form, int c);
11 int form_driver_w(FORM *form, int c, wchar_t wch);
12
14 form_driver
15 Once a form has been posted (displayed), you should funnel input events
16 to it through form_driver. This routine has three major input cases:
17 · The input is a form navigation request. Navigation request codes
19 are constants defined in <form.h>, which are distinct from the key-
20 and character codes returned by wgetch(3X).
21 · The input is a printable character. Printable characters (which
23 must be positive, less than 256) are checked according to the pro‐
24 gram's locale settings.
25 · The input is the KEY_MOUSE special key associated with an mouse
27 event.
28 form_driver_w
30 This extension simplifies the use of the forms library using wide char‐
31 acters. The input is either a key code (a request) or a wide character
32 returned by get_wch(3X). The type must be passed as well, to enable
33 the library to determine whether the parameter is a wide character or a
34 request.
35 Form-driver requests
37 The form driver requests are as follows:
38 Name Description
40 ─────────────────────────────────────────────────────────────────────
41 REQ_BEG_FIELD Move to the beginning of the field.
42 REQ_BEG_LINE Move to the beginning of the line.
43 REQ_CLR_EOF Clear to end of field from cursor.
44 REQ_CLR_EOL Clear to end of line from cursor.
45 REQ_CLR_FIELD Clear the entire field.
46 REQ_DEL_CHAR Delete character at the cursor.
47 REQ_DEL_LINE Delete line at the cursor.
48 REQ_DEL_PREV Delete character before the cursor.
49 REQ_DEL_WORD Delete blank-delimited word at the cursor.
50 REQ_DOWN_CHAR Move down in the field.
51 REQ_DOWN_FIELD Move down to a field.
52 REQ_END_FIELD Move to the end of the field.
53 REQ_END_LINE Move to the end of the line.
54 REQ_FIRST_FIELD Move to the first field.
55 REQ_FIRST_PAGE Move to the first page.
56 REQ_INS_CHAR Insert a blank at the cursor.
57 REQ_INS_LINE Insert a blank line at the cursor.
58 REQ_INS_MODE Enter insert mode.
59 REQ_LAST_FIELD Move to the last field.
60 REQ_LAST_PAGE Move to the last field.
61 REQ_LEFT_CHAR Move left in the field.
62 REQ_LEFT_FIELD Move left to a field.
63 REQ_NEW_LINE Insert or overlay a new line.
64 REQ_NEXT_CHAR Move to the next char.
65 REQ_NEXT_CHOICE Display next field choice.
66 REQ_NEXT_FIELD Move to the next field.
68 REQ_NEXT_LINE Move to the next line.
69 REQ_NEXT_PAGE Move to the next page.
70 REQ_NEXT_PAGE Move to the next page.
71 REQ_NEXT_WORD Move to the next word.
72 REQ_OVL_MODE Enter overlay mode.
73 REQ_PREV_CHAR Move to the previous char.
74 REQ_PREV_CHOICE Display previous field choice.
75 REQ_PREV_FIELD Move to the previous field.
76 REQ_PREV_LINE Move to the previous line.
77 REQ_PREV_PAGE Move to the previous page.
78 REQ_PREV_WORD Move to the previous word.
79 REQ_RIGHT_CHAR Move right in the field.
80 REQ_RIGHT_FIELD Move right to a field.
81 REQ_SCR_BCHAR Scroll the field backward a character.
82 REQ_SCR_BHPAGE Scroll the field backward half a page.
83 REQ_SCR_BLINE Scroll the field backward a line.
84 REQ_SCR_BPAGE Scroll the field backward a page.
85 REQ_SCR_FCHAR Scroll the field forward a character.
86 REQ_SCR_FHPAGE Scroll the field forward half a page.
87 REQ_SCR_FLINE Scroll the field forward a line.
88 REQ_SCR_FPAGE Scroll the field forward a page.
89 REQ_SCR_HBHALF Horizontal scroll the field backward half a line.
90 REQ_SCR_HBLINE Horizontal scroll the field backward a line.
91 REQ_SCR_HFHALF Horizontal scroll the field forward half a line.
92 REQ_SCR_HFLINE Horizontal scroll the field forward a line.
93 REQ_SFIRST_FIELD Move to the sorted first field.
94 REQ_SLAST_FIELD Move to the sorted last field.
95 REQ_SNEXT_FIELD Move to the sorted next field.
96 REQ_SPREV_FIELD Move to the sorted previous field.
97 REQ_UP_CHAR Move up in the field.
98 REQ_UP_FIELD Move up to a field.
99 REQ_VALIDATION Validate field.
100 If the second argument is a printable character, the driver places it
102 in the current position in the current field. If it is one of the
103 forms requests listed above, that request is executed.
104 Field validation
106 The form library makes updates to the window associated with form
107 fields rather than directly to the field buffers.
108 The form driver provides low-level control over updates to the form
110 fields. The form driver also provides for validating modified fields
111 to ensure that the contents meet whatever constraints an application
112 may attach using set_field_type.
113 You can validate a field without making any changes to it using
115 REQ_VALIDATION. The form driver also validates a field in these cases:
116 · a call to set_current_field attempts to move to a different field.
118 · a call to set_current_page attempts to move to a different page of
120 the form.
121 · a request attempts to move to a different field.
123 · a request attempts to move to a different page of the form.
125 In each case, the move fails if the field is invalid.
127 If the modified field is valid, the form driver copies the modified
129 data from the window associated with the field to the field buffer.
130 Mouse handling
132 If the second argument is the KEY_MOUSE special key, the associated
133 mouse event is translated into one of the above pre-defined requests.
134 Currently only clicks in the user window (e.g., inside the form display
135 area or the decoration window) are handled.
136 If you click above the display region of the form:
138 a REQ_PREV_FIELD is generated for a single click,
140 a REQ_PREV_PAGE is generated for a double-click and
142 a REQ_FIRST_FIELD is generated for a triple-click.
144 If you click below the display region of the form:
146 a REQ_NEXT_FIELD is generated for a single click,
148 a REQ_NEXT_PAGE is generated for a double-click and
150 a REQ_LAST_FIELD is generated for a triple-click.
152 If you click at an field inside the display area of the form:
154 · the form cursor is positioned to that field.
156 · If you double-click a field, the form cursor is positioned to
158 that field and E_UNKNOWN_COMMAND is returned. This return value
159 makes sense, because a double click usually means that an field-
160 specific action should be returned. It is exactly the purpose
161 of this return value to signal that an application specific com‐
162 mand should be executed.
163 · If a translation into a request was done, form_driver returns
165 the result of this request.
166 If you clicked outside the user window or the mouse event could not be
168 translated into a form request an E_REQUEST_DENIED is returned.
169 Application-defined commands
171 If the second argument is neither printable nor one of the above pre-
172 defined form requests, the driver assumes it is an application-specific
173 command and returns E_UNKNOWN_COMMAND. Application-defined commands
174 should be defined relative to MAX_COMMAND, the maximum value of these
175 pre-defined requests.
176
178 form_driver returns one of the following error codes:
179 E_OK The routine succeeded.
181 E_BAD_ARGUMENT
183 Routine detected an incorrect or out-of-range argument.
184 E_BAD_STATE
186 Routine was called from an initialization or termination function.
187 E_NOT_POSTED
189 The form has not been posted.
190 E_INVALID_FIELD
192 Contents of field is invalid.
193 E_REQUEST_DENIED
195 The form driver could not process the request.
196 E_SYSTEM_ERROR
198 System error occurred (see errno).
199 E_UNKNOWN_COMMAND
201 The form driver code saw an unknown request code.
202
204 curses(3X), form(3X), form_field_buffer(3X), form_field_validation(3X),
205 form_fieldtype(3X), form_variables(3X), getch(3X).
206
208 The header file <form.h> automatically includes the header files
209 <curses.h>.
210
212 These routines emulate the System V forms library. They were not sup‐
213 ported on Version 7 or BSD versions.
214
216 Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S.
217 Raymond.
218 form_driver(3X)