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<pre>
<span class="headline">form_field_buffer(3X)                                  form_field_buffer(3X)</span>
</pre>
<h2><a id="NAME" href="form_field_buffer.3x.html#NAME"></a>NAME  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       <b>form_field_buffer </b>- field buffer control
</pre>
<h2><a id="SYNOPSIS" href="form_field_buffer.3x.html#SYNOPSIS"></a>SYNOPSIS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       <b>#include &lt;form.h&gt;</b>

       int set_field_buffer(FIELD *field, int buf, const char *value);
       char *field_buffer(const FIELD *field, int buffer);
       int set_field_status(FIELD *field, bool status);
       bool field_status(const FIELD *field);
       int set_max_field(FIELD *field, int max);
</pre>
<h2><a id="DESCRIPTION" href="form_field_buffer.3x.html#DESCRIPTION"></a>DESCRIPTION  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The function <b>set_field_buffer </b>sets the numbered buffer of the given
       field to contain a given string:

          ·   Buffer 0 is the displayed value of the field.

          ·   Other numbered buffers may be allocated by applications
              through the <b>nbuf </b>argument of (see <b>form_field_new</b>(3X)) but are
              not manipulated by the forms library.

       The function <b>field_buffer </b>returns a pointer to the contents of the
       given numbered buffer:

          ·   The buffer contents always have the same length, and are
              padded with trailing spaces as needed to ensure this length is
              the same.

          ·   The buffer may contain leading spaces, depending on how it was
              set.

          ·   The buffer contents are set with <b>set_field_buffer</b>, or as a
              side effect of any editing operations on the corresponding
              field.

          ·   Editing operations are based on the <i>window</i> which displays the
              field, rather than a <i>string</i>.  The window contains only
              printable characters, and is filled with blanks.  If you want
              the raw data, you must write your own routine that copies the
              value out of the buffer and removes the leading and trailing
              spaces.

          ·   Because editing operations change the content of the buffer to
              correspond to the window, you should not rely on using buffers
              for long-term storage of form data.

       The function <b>set_field_status </b>sets the associated status flag of
       <i>field</i>; <b>field_status </b>gets the current value.  The status flag is set
       to a nonzero value whenever the field changes.

       The function <b>set_max_field </b>sets the maximum size for a dynamic field.
       An argument of 0 turns off any maximum size threshold for that field.
</pre>
<h2><a id="RETURN_VALUE" href="form_field_buffer.3x.html#RETURN_VALUE"></a>RETURN VALUE  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The <b>field_buffer </b>function returns NULL on error.  It sets errno
       according to their success:

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

       <b>E_BAD_ARGUMENT</b>
            Routine detected an incorrect or out-of-range argument.

       The <b>field_status </b>function returns <b>TRUE </b>or <b>FALSE</b>.

       The remaining routines return one of the following:

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

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

       <b>E_BAD_ARGUMENT</b>
            Routine detected an incorrect or out-of-range argument.
</pre>
<h2><a id="SEE_ALSO" href="form_field_buffer.3x.html#SEE_ALSO"></a>SEE ALSO  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       <b>curses</b>(3X) and related pages whose names begin "form_" for detailed
       descriptions of the entry points.
</pre>
<h2><a id="NOTES" href="form_field_buffer.3x.html#NOTES"></a>NOTES  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       The header file <b>&lt;form.h&gt; </b>automatically includes the header file

       When configured for wide characters, <b>field_buffer </b>returns a pointer
       to temporary storage (allocated and freed by the library).  The
       application should not attempt to modify the data.  It will be freed
       on the next call to <b>field_buffer </b>to return the same buffer.
       <b>&lt;curses.h&gt;</b>.
</pre>
<h2><a id="PORTABILITY" href="form_field_buffer.3x.html#PORTABILITY"></a>PORTABILITY  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       These routines emulate the System V forms library.  They were not
       supported on Version 7 or BSD versions.
</pre>
<h2><a id="AUTHORS" href="form_field_buffer.3x.html#AUTHORS"></a>AUTHORS  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       Juergen Pfeifer.  Manual pages and adaptation for new curses by Eric
       S. Raymond.
</pre>
<h2><a id="COLOPHON" href="form_field_buffer.3x.html#COLOPHON"></a>COLOPHON  &nbsp; &nbsp; &nbsp; &nbsp; <a href="form_field_buffer.3x.html#top_of_page"><span class="top-link">top</span></a></h2><pre>
       This page is part of the <i>ncurses</i> (new curses) project.  Information
       about the project can be found at 
       ⟨<a href="https://www.gnu.org/software/ncurses/ncurses.html">https://www.gnu.org/software/ncurses/ncurses.html</a>⟩.  If you have a
       bug report for this manual page, send it to
       bug-ncurses-request@gnu.org.  This page was obtained from the
       project's upstream Git mirror of the CVS repository
       ⟨git://ncurses.scripts.mit.edu/ncurses.git⟩ on 2018-02-02.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2018-01-30.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is <i>not</i> part
       of the original manual page), send a mail to man-pages@man7.org

<span class="footline">                                                       form_field_buffer(3X)</span>
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