doc/html/man/form_fieldtype.3x.html

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  43 <H1 class="no-header">form_fieldtype 3x</H1>
  44 <PRE>
  45 <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>                                          <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
  46
  47
  48
  49
  50 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
  51        <STRONG>form_fieldtype</STRONG> - define validation-field types
  52
  53
  54 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
  55        <STRONG>#include</STRONG> <STRONG>&lt;form.h&gt;</STRONG>
  56
  57        <STRONG>FIELDTYPE</STRONG> <STRONG>*new_fieldtype(</STRONG>
  58            <STRONG>bool</STRONG> <STRONG>(*</STRONG> <STRONG>const</STRONG> <EM>field</EM><STRONG>_</STRONG><EM>check</EM><STRONG>)(FIELD</STRONG> <STRONG>*,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*),</STRONG>
  59            <STRONG>bool</STRONG> <STRONG>(*</STRONG> <STRONG>const</STRONG> <EM>char</EM><STRONG>_</STRONG><EM>check</EM><STRONG>)(int,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*));</STRONG>
  60        <STRONG>int</STRONG> <STRONG>free_fieldtype(FIELDTYPE</STRONG> <STRONG>*</STRONG><EM>fieldtype</EM><STRONG>);</STRONG>
  61
  62        <STRONG>int</STRONG> <STRONG>set_fieldtype_arg(</STRONG>
  63            <STRONG>FIELDTYPE</STRONG> <STRONG>*</STRONG><EM>fieldtype</EM><STRONG>,</STRONG>
  64            <STRONG>void</STRONG> <STRONG>*(*</STRONG> <STRONG>const</STRONG> <EM>make</EM><STRONG>_</STRONG><EM>arg</EM><STRONG>)(va_list</STRONG> <STRONG>*),</STRONG>
  65            <STRONG>void</STRONG> <STRONG>*(*</STRONG> <STRONG>const</STRONG> <EM>copy</EM><STRONG>_</STRONG><EM>arg</EM><STRONG>)(const</STRONG> <STRONG>void</STRONG> <STRONG>*),</STRONG>
  66            <STRONG>void</STRONG>  <STRONG>(*</STRONG> <STRONG>const</STRONG> <EM>free</EM><STRONG>_</STRONG><EM>arg</EM><STRONG>)(void</STRONG> <STRONG>*));</STRONG>
  67        <STRONG>int</STRONG> <STRONG>set_fieldtype_choice(</STRONG>
  68            <STRONG>FIELDTYPE</STRONG> <STRONG>*</STRONG><EM>fieldtype</EM><STRONG>,</STRONG>
  69            <STRONG>bool</STRONG> <STRONG>(*</STRONG> <STRONG>const</STRONG> <EM>next</EM><STRONG>_</STRONG><EM>choice</EM><STRONG>)(FIELD</STRONG> <STRONG>*,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*),</STRONG>
  70            <STRONG>bool</STRONG> <STRONG>(*</STRONG> <STRONG>const</STRONG> <EM>prev</EM><STRONG>_</STRONG><EM>choice</EM><STRONG>)(FIELD</STRONG> <STRONG>*,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*));</STRONG>
  71
  72        <STRONG>FIELDTYPE</STRONG> <STRONG>*link_fieldtype(FIELDTYPE</STRONG> <STRONG>*</STRONG><EM>type1</EM><STRONG>,</STRONG>
  73                                  <STRONG>FIELDTYPE</STRONG> <STRONG>*</STRONG><EM>type2</EM><STRONG>);</STRONG>
  74
  75
  76 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
  77
  78 </PRE><H3><a name="h3-new_fieldtype">new_fieldtype</a></H3><PRE>
  79        The  function  <STRONG>new_fieldtype</STRONG>  creates  a new field type usable for data
  80        validation.  Its parameters are function pointers:
  81
  82        <EM>field</EM><STRONG>_</STRONG><EM>check</EM>
  83             This function checks  the  validity  of  an  entered  data  string
  84             whenever  the  user  attempts  to  leave  a  field.   It  has  two
  85             arguments:
  86
  87             <STRONG>o</STRONG>   The  (FIELD  *)  argument  is  passed  in  so  the  validation
  88                 predicate   can  see  the  field's  buffer,  sizes  and  other
  89                 attributes.
  90
  91             <STRONG>o</STRONG>   The second argument  is  an  argument-block  structure,  about
  92                 which more below.
  93
  94        <EM>char</EM><STRONG>_</STRONG><EM>check</EM>
  95             This function validates input characters as they are entered.  The
  96             form library passes it the character to be checked and  a  pointer
  97             to an argument-block structure.
  98
  99
 100 </PRE><H3><a name="h3-free_fieldtype">free_fieldtype</a></H3><PRE>
 101        The  <STRONG>free_fieldtype</STRONG>  function  frees  the  space  allocated for a given
 102        validation type by <STRONG>new_fieldtype</STRONG>.
 103
 104
 105 </PRE><H3><a name="h3-set_fieldtype_arg">set_fieldtype_arg</a></H3><PRE>
 106        The  function  <STRONG>set_fieldtype_arg</STRONG>  associates  three  storage-management
 107        functions with a field type:
 108
 109        <EM>make</EM><STRONG>_</STRONG><EM>arg</EM>
 110             This  function  is  automatically applied to the list of arguments
 111             you give <STRONG>set_field_type</STRONG> when attaching validation to a field.   It
 112             stores  the  arguments in an allocated argument-block object which
 113             is used when validating input.
 114
 115        <EM>copy</EM><STRONG>_</STRONG><EM>arg</EM>
 116             This function may be used by applications to copy argument-blocks.
 117
 118        <EM>free</EM><STRONG>_</STRONG><EM>arg</EM>
 119             Frees an argument-block structure.
 120
 121        You must supply the <EM>make</EM><STRONG>_</STRONG><EM>arg</EM> function.  The other two are optional: you
 122        may  supply NULL for them.  In this case, the form library assumes that
 123        <EM>make</EM><STRONG>_</STRONG><EM>arg</EM> does not allocate memory but simply loads the argument into  a
 124        single scalar value.
 125
 126
 127 </PRE><H3><a name="h3-set_fieldtype_choice">set_fieldtype_choice</a></H3><PRE>
 128        The  form  driver  requests  <STRONG>REQ_NEXT_CHOICE</STRONG> and <STRONG>REQ_PREV_CHOICE</STRONG> assume
 129        that the possible values of a field form an ordered  set,  and  provide
 130        the forms user with a way to move through the set.
 131
 132        The  <STRONG>set_fieldtype_choice</STRONG>  function  allows forms programmers to define
 133        successor  and  predecessor  functions  for  the  field  type.    These
 134        functions  take  the  field  pointer and an argument-block structure as
 135        arguments.
 136
 137
 138 </PRE><H3><a name="h3-link_fieldtype">link_fieldtype</a></H3><PRE>
 139        The function <STRONG>link_fieldtype</STRONG> creates a new field type from the two given
 140        types.  They are connected by an logical 'OR'.
 141
 142
 143 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
 144        The  pointer-valued  routines  return  NULL  on  error.  They set <STRONG>errno</STRONG>
 145        according to their success:
 146
 147        <STRONG>E_OK</STRONG> The routine succeeded.
 148
 149        <STRONG>E_BAD_ARGUMENT</STRONG>
 150             Routine detected an incorrect or out-of-range argument.
 151
 152        <STRONG>E_SYSTEM_ERROR</STRONG>
 153             System error occurred, e.g., malloc failure.
 154
 155        The integer-valued routines return one of the following codes on error:
 156
 157        <STRONG>E_OK</STRONG> The routine succeeded.
 158
 159        <STRONG>E_BAD_ARGUMENT</STRONG>
 160             Routine detected an incorrect or out-of-range argument.
 161
 162        <STRONG>E_CONNECTED</STRONG>
 163             The field is already connected to a form.
 164
 165        <STRONG>E_CURRENT</STRONG>
 166             The field is the current field.
 167
 168        <STRONG>E_SYSTEM_ERROR</STRONG>
 169             System error occurred (see <STRONG>errno(3)</STRONG>).
 170
 171
 172 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
 173        <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="form.3x.html">form(3x)</A></STRONG>, <STRONG><A HREF="form_field_validation.3x.html">form_field_validation(3x)</A></STRONG>.
 174
 175
 176 </PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
 177        The  header  file  <STRONG>&lt;form.h&gt;</STRONG>  automatically  includes  the  header  file
 178        <STRONG>&lt;curses.h&gt;</STRONG>.
 179
 180
 181 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
 182        These  routines  emulate  the  System  V  forms library.  They were not
 183        supported on Version 7 or BSD versions.
 184
 185
 186 </PRE><H2><a name="h2-AUTHORS">AUTHORS</a></H2><PRE>
 187        Juergen Pfeifer.  Manual pages and adaptation for new curses by Eric S.
 188        Raymond.
 189
 190
 191
 192                                                             <STRONG><A HREF="form_fieldtype.3x.html">form_fieldtype(3x)</A></STRONG>
 193 </PRE>
 194 <div class="nav">
 195 <ul>
 196 <li><a href="#h2-NAME">NAME</a></li>
 197 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
 198 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
 199 <ul>
 200 <li><a href="#h3-new_fieldtype">new_fieldtype</a></li>
 201 <li><a href="#h3-free_fieldtype">free_fieldtype</a></li>
 202 <li><a href="#h3-set_fieldtype_arg">set_fieldtype_arg</a></li>
 203 <li><a href="#h3-set_fieldtype_choice">set_fieldtype_choice</a></li>
 204 <li><a href="#h3-link_fieldtype">link_fieldtype</a></li>
 205 </ul>
 206 </li>
 207 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
 208 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
 209 <li><a href="#h2-NOTES">NOTES</a></li>
 210 <li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
 211 <li><a href="#h2-AUTHORS">AUTHORS</a></li>
 212 </ul>
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