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<H1>form_driver 3x</H1>
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<!-- Manpage converted by man2html 3.0.1 -->
<STRONG><A HREF="form_driver.3x.html">form_driver(3x)</A></STRONG>                                         <STRONG><A HREF="form_driver.3x.html">form_driver(3x)</A></STRONG>


</PRE>
<H2>NAME</H2><PRE>
       <STRONG>form_driver</STRONG> - command-processing loop of the form system


</PRE>
<H2>SYNOPSIS</H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;form.h&gt;</STRONG>
       int form_driver(FORM *form, int c);


</PRE>
<H2>DESCRIPTION</H2><PRE>
       Once a form has been posted (displayed), you should funnel
       input events to it through <STRONG>form_driver</STRONG>.  This routine  has
       three major input cases:

       -  The  input  is  a  form navigation request.  Navigation
          request codes are constants defined in <STRONG>&lt;form.h&gt;</STRONG>,  which
          are distinct from the key- and character codes returned
          by <STRONG>wgetch</STRONG>.

       -  The input is a printable character.  Printable  charac-
          ters  (which  must  be  positive,  less  than  256) are
          checked according to the program's locale settings.

       -  The input is the KEY_MOUSE special key associated  with
          an mouse event.

       The form driver requests are as follows:

       REQ_NEXT_PAGE
            Move to the next page.

       REQ_PREV_PAGE
            Move to the previous page.

       REQ_FIRST_PAGE
            Move to the first page.

       REQ_LAST_PAGE
            Move to the last field.


       REQ_NEXT_FIELD
            Move to the next field.

       REQ_PREV_FIELD
            Move to the previous field.

       REQ_FIRST_FIELD
            Move to the first field.

       REQ_LAST_FIELD
            Move to the last field.

       REQ_SNEXT_FIELD
            Move to the sorted next field.

       REQ_SPREV_FIELD
            Move to the sorted previous field.

       REQ_SFIRST_FIELD
            Move to the sorted first field.

       REQ_SLAST_FIELD
            Move to the sorted last field.

       REQ_LEFT_FIELD
            Move left to a field.

       REQ_RIGHT_FIELD
            Move right to a field.

       REQ_UP_FIELD
            Move up to a field.

       REQ_DOWN_FIELD
            Move down to a field.


       REQ_NEXT_CHAR
            Move to the next char.

       REQ_PREV_CHAR
            Move to the previous char.

       REQ_NEXT_LINE
            Move to the next line.

       REQ_PREV_LINE
            Move to the previous line.

       REQ_NEXT_WORD
            Move to the next word.

       REQ_PREV_WORD
            Move to the previous word.

       REQ_BEG_FIELD
            Move to the beginning of the field.

       REQ_END_FIELD
            Move to the end of the field.

       REQ_BEG_LINE
            Move to the beginning of the line.

       REQ_END_LINE
            Move to the end of the line.

       REQ_LEFT_CHAR
            Move left in the field.

       REQ_RIGHT_CHAR
            Move right in the field.

       REQ_UP_CHAR
            Move up in the field.

       REQ_DOWN_CHAR
            Move down in the field.


       REQ_NEW_LINE
            Insert or overlay a new line.

       REQ_INS_CHAR
            Insert a blank at the cursor.

       REQ_INS_LINE
            Insert a blank line at the cursor.

       REQ_DEL_CHAR
            Delete character at the cursor.

       REQ_DEL_PREV
            Delete character before the cursor.

       REQ_DEL_LINE
            Delete line at the cursor.

       REQ_DEL_WORD
            Delete blank-delimited word at the cursor.

       REQ_CLR_EOL
            Clear to end of line from cursor.

       REQ_CLR_EOF
            Clear to end of field from cursor.

       REQ_CLR_FIELD
            Clear the entire field.

       REQ_OVL_MODE
            Enter overlay mode.

       REQ_INS_MODE
            Enter insert mode.


       REQ_SCR_FLINE
            Scroll the field forward a line.

       REQ_SCR_BLINE
            Scroll the field backward a line.

       REQ_SCR_FPAGE
            Scroll the field forward a page.

       REQ_SCR_BPAGE
            Scroll the field backward a page.

       REQ_SCR_FHPAGE
            Scroll the field forward half a page.

       REQ_SCR_BHPAGE
            Scroll the field backward half a page.


       REQ_SCR_FCHAR
            Scroll the field forward a character.

       REQ_SCR_BCHAR
            Scroll the field backward a character.

       REQ_SCR_HFLINE
            Horizontal scroll the field forward a line.

       REQ_SCR_HBLINE
            Horizontal scroll the field backward a line.

       REQ_SCR_HFHALF
            Horizontal scroll the field forward half a line.

       REQ_SCR_HBHALF
            Horizontal scroll the field backward half a line.


       REQ_VALIDATION
            Validate field.

       REQ_NEXT_CHOICE
            Display next field choice.

       REQ_PREV_CHOICE
            Display previous field choice.

       If  the  second  argument  is  a  printable character, the
       driver places it in the current position  in  the  current
       field.   If  it is one of the forms requests listed above,
       that request is executed.

   <STRONG>MOUSE</STRONG> <STRONG>HANDLING</STRONG>
       If the second argument is the KEY_MOUSE special  key,  the
       associated mouse event is translated into one of the above
       pre-defined requests.  Currently only clicks in  the  user
       window  (e.g.  inside the form display area or the decora-
       tion window) are handled.

       If you click above the display region of the form:

              a REQ_PREV_FIELD is generated for a single click,

              a REQ_PREV_PAGE is generated for a double-click and

              a REQ_FIRST_FIELD is generated for a  triple-click.

       If you click below the display region of the form:

              a REQ_NEXT_FIELD is generated for a single click,

              a REQ_NEXT_PAGE is generated for a double-click and

              a REQ_LAST_FIELD is generated for a triple-click.

       If you click at an field inside the display  area  of  the
       form:

              -  the form cursor is positioned to that field.

              -  If  you double-click a field, the form cursor is
                 positioned to that field  and  <STRONG>E_UNKNOWN_COMMAND</STRONG>
                 is  returned.   This  return  value makes sense,
                 because a double click  usually  means  that  an
                 field-specific action should be returned.  It is
                 exactly the purpose of this return value to sig-
                 nal  that an application specific command should
                 be executed.

              -  If  a  translation  into  a  request  was  done,
                 <STRONG>form_driver</STRONG>  returns the result of this request.

       If you clicked outside the user window or the mouse  event
       could   not   be   translated   into  a  form  request  an
       <STRONG>E_REQUEST_DENIED</STRONG> is returned.

   <STRONG>APPLICATION-DEFINED</STRONG> <STRONG>COMMANDS</STRONG>
       If the second argument is neither printable nor one of the
       above  pre-defined form requests, the driver assumes it is
       an application-specific command and returns <STRONG>E_UNKNOWN_COM-</STRONG>
       <STRONG>MAND</STRONG>.  Application-defined commands should be defined rel-
       ative to <STRONG>MAX_COMMAND</STRONG>, the  maximum  value  of  these  pre-
       defined requests.


</PRE>
<H2>RETURN VALUE</H2><PRE>
       <STRONG>form_driver</STRONG> returns one of the following error codes:

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

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

       <STRONG>E_BAD_STATE</STRONG>
            Routine was called from an initialization or termina-
            tion function.

       <STRONG>E_NOT_POSTED</STRONG>
            The form has not been posted.

       <STRONG>E_INVALID_FIELD</STRONG>
            Contents of field is invalid.

       <STRONG>E_REQUEST_DENIED</STRONG>
            The form driver could not process the request.

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

       <STRONG>E_UNKNOWN_COMMAND</STRONG>
            The form driver code saw an unknown request code.


</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>, <STRONG><A HREF="wgetch.3x.html">wgetch(3x)</A></STRONG>.


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


</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_driver.3x.html">form_driver(3x)</A></STRONG>
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