aboutsummaryrefslogtreecommitdiff
path: root/doc/html/man/form_fieldtype.3x.html
blob: 7f195ee37a8c466d38bc1373ca298d91266dc838 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<!-- 
  * t
  ****************************************************************************
  * Copyright (c) 1998-2006,2010 Free Software Foundation, Inc.              *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
  * "Software"), to deal in the Software without restriction, including      *
  * without limitation the rights to use, copy, modify, merge, publish,      *
  * distribute, distribute with modifications, sublicense, and/or sell       *
  * copies of the Software, and to permit persons to whom the Software is    *
  * furnished to do so, subject to the following conditions:                 *
  *                                                                          *
  * The above copyright notice and this permission notice shall be included  *
  * in all copies or substantial portions of the Software.                   *
  *                                                                          *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
  *                                                                          *
  * Except as contained in this notice, the name(s) of the above copyright   *
  * holders shall not be used in advertising or otherwise to promote the     *
  * sale, use or other dealings in this Software without prior written       *
  * authorization.                                                           *
  ****************************************************************************
  * @Id: form_fieldtype.3x,v 1.16 2010/12/04 18:40:45 tom Exp @
-->
<HTML>
<HEAD>
<TITLE>form_fieldtype 3x</TITLE>
<link rev=made href="mailto:bug-ncurses@gnu.org">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</HEAD>
<BODY>
<H1>form_fieldtype 3x</H1>
<HR>
<PRE>
<!-- Manpage converted by man2html 3.0.1 -->
<STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>                                   <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>




</PRE>
<H2>NAME</H2><PRE>
       <STRONG>form_fieldtype</STRONG> - define validation-field types


</PRE>
<H2>SYNOPSIS</H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;form.h&gt;</STRONG>
       FIELDTYPE *new_fieldtype(
           bool (* const field_check)(FIELD *, const void *),
           bool (* const char_check)(int, const void *));
       int free_fieldtype(FIELDTYPE *fieldtype);
       int set_fieldtype_arg(
           FIELDTYPE *fieldtype,
           void *(* const make_arg)(va_list *),
           void *(* const copy_arg)(const void *),
           void  (* const free_arg)(void *));
       int set_fieldtype_choice(
           FIELDTYPE *fieldtype,
           bool (* const next_choice)(FIELD *, const void *),
           bool (* const prev_choice)(FIELD *, const void *));
       FIELDTYPE *link_fieldtype(FIELDTYPE *type1,
                                 FIELDTYPE *type2);


</PRE>
<H2>DESCRIPTION</H2><PRE>
       The function <STRONG>new_fieldtype</STRONG> creates a new field type usable
       for data validation.  You supply it  with  <EM>field</EM><STRONG>_</STRONG><EM>check</EM>,  a
       predicate  to check the validity of an entered data string
       whenever the user attempts to leave a field.   The  (FIELD
       *)  argument  is passed in so the validation predicate can
       see the field's buffer, sizes and  other  attributes;  the
       second  argument  is  an  argument-block  structure, about
       which more below.

       You also supply <STRONG>new_fieldtype</STRONG> with <EM>char</EM><STRONG>_</STRONG><EM>check</EM>, a  function
       to  validate input characters as they are entered; it will
       be passed the character to be checked and a pointer to  an
       argument-block structure.

       The  function <STRONG>free_fieldtype</STRONG> frees the space allocated for
       a given validation type.

       The function <STRONG>set_fieldtype_arg</STRONG> associates  three  storage-
       management  functions  with  a  field  type.  The <EM>make</EM><STRONG>_</STRONG><EM>arg</EM>
       function is automatically applied to the list of arguments
       you  give  <STRONG>set_field_type</STRONG>  when  attaching validation to a
       field; its job is to bundle these into an allocated  argu-
       ment-block  object which can later be passed to validation
       predicated.  The other two hook arguments should copy  and
       free  argument-block structures.  They will be used by the
       forms-driver code.  You must supply the <EM>make</EM><STRONG>_</STRONG><EM>arg</EM> function,
       the  other two are optional, you may supply NULL for them.
       In this case it is assumed that <EM>make</EM><STRONG>_</STRONG><EM>arg</EM> does not allocate
       memory  but simply loads the argument into a single scalar
       value.

       The function <STRONG>link_fieldtype</STRONG> creates a new field type  from
       the  two  given  types.   They are connected by an logical
       'OR'.

       The   form    driver    requests    <STRONG>REQ_NEXT_CHOICE</STRONG>    and
       <STRONG>REQ_PREV_CHOICE</STRONG> assume that the possible values of a field
       form an ordered set, and provide the forms user with a way
       to  move  through the set.  The <STRONG>set_fieldtype_choice</STRONG> func-
       tion allows forms  programmers  to  define  successor  and
       predecessor functions for the field type.  These functions
       take the field pointer and an argument-block structure  as
       arguments.


</PRE>
<H2>RETURN VALUE</H2><PRE>
       The  pointer-valued  routines  return NULL on error.  They
       set errno according to their success:

       <STRONG>E_OK</STRONG> The routine succeeded.

       <STRONG>E_BAD_ARGUMENT</STRONG>
            Routine detected an incorrect or  out-of-range  argu-
            ment.

       <STRONG>E_SYSTEM_ERROR</STRONG>
            System error occurred, e.g., malloc failure.

       The  integer-valued  routines  return one of the following
       codes on error:

       <STRONG>E_OK</STRONG> The routine succeeded.

       <STRONG>E_BAD_ARGUMENT</STRONG>
            Routine detected an incorrect or  out-of-range  argu-
            ment.

       <STRONG>E_CONNECTED</STRONG>
            The field is already connected to a form.

       <STRONG>E_CURRENT</STRONG>
            The field is the current field.

       <STRONG>E_SYSTEM_ERROR</STRONG>
            System error occurred (see <STRONG>errno</STRONG>).


</PRE>
<H2>SEE ALSO</H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>.


</PRE>
<H2>NOTES</H2><PRE>
       The header file <STRONG>&lt;form.h&gt;</STRONG> automatically includes the header
       file <STRONG>&lt;curses.h&gt;</STRONG>.

       All of the <STRONG>(char</STRONG> <STRONG>*)</STRONG> arguments of  these  functions  should
       actually  be <STRONG>(void</STRONG> <STRONG>*)</STRONG>.  The type has been left uncorrected
       for strict compatibility with System V.


</PRE>
<H2>PORTABILITY</H2><PRE>
       These routines emulate the System V forms  library.   They
       were not supported on Version 7 or BSD versions.


</PRE>
<H2>AUTHORS</H2><PRE>
       Juergen  Pfeifer.   Manual  pages  and  adaptation for new
       curses by Eric S. Raymond.



                                                     <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
</PRE>
<HR>
<ADDRESS>
Man(1) output converted with
<a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a>
</ADDRESS>
</BODY>
</HTML>