.\"***************************************************************************
-.\" Copyright (c) 1998-2016,2017 Free Software Foundation, Inc. *
+.\" Copyright 2018-2020,2021 Thomas E. Dickey *
+.\" Copyright 1998-2016,2017 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 *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: form_driver.3x,v 1.27 2017/06/23 22:56:39 tom Exp $
+.\" $Id: form_driver.3x,v 1.38 2021/12/25 21:49:32 tom Exp $
.TH form_driver 3X ""
.de bP
-.IP \(bu 4
+.ie n .IP \(bu 4
+.el .IP \(bu 2
..
.SH NAME
-\fBform_driver\fR,
-\fBform_driver_w\fR \- command-processing loop of the form system
+\fBform_driver\fP,
+\fBform_driver_w\fP \- command-processing loop of the form system
.SH SYNOPSIS
-\fB#include <form.h>\fR
-.br
+\fB#include <form.h>\fP
+.sp
\fBint form_driver(FORM *\fP\fIform\fP\fB, int \fP\fIc\fP\fB);\fP
.br
\fBint form_driver_w(FORM *\fP\fIform\fP\fB, int \fP\fIc\fP\fB, wchar_t \fP\fIwch\fP\fB);\fP
.SH DESCRIPTION
.SS form_driver
Once a form has been posted (displayed), you should funnel input events to it
-through \fBform_driver\fR. This routine has three major input cases:
+through \fBform_driver\fP. This routine has three major input cases:
.bP
The input is a form navigation request.
Navigation request codes are constants defined in \fB<form.h>\fP,
-which are distinct from the key- and character codes returned by \fBwgetch\fP(3X).
+which are distinct from the key- and character codes returned
+by \fBwgetch\fP(3X).
.bP
The input is a printable character.
Printable characters (which must be positive, less than 256) are
l l
_ _
l l.
-\fIName\fR \fIDescription\fR
+\fBName\fP \fBDescription\fP
REQ_BEG_FIELD Move to the beginning of the field.
REQ_BEG_LINE Move to the beginning of the line.
REQ_CLR_EOF Clear to end of field from cursor.
.TE
.PP
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
+in the current position in the current field.
+If it is one of the forms
requests listed above, that request is executed.
.SS Field validation
-The form library makes updates to the window associated with form fields rather than
-directly to the field buffers.
+The form library makes updates to the window associated
+with form fields rather than directly to the field buffers.
.PP
The form driver provides low-level control over updates to the form fields.
-The form driver also provides for validating modified fields to ensure that the contents
+The form driver also provides for validating modified fields
+to ensure that the contents
meet whatever constraints an application may attach using \fBset_field_type\fP.
.PP
.PP
.bP
a call to \fBset_current_field\fP attempts to move to a different field.
.bP
-a call to \fBset_current_page\fP attempts to move to a different page of the form.
+a call to \fBset_current_page\fP attempts to move
+to a different page of the form.
.bP
a request attempts to move to a different field.
.bP
.bP
If you double-click a field,
the form cursor is positioned to that field
-and \fBE_UNKNOWN_COMMAND\fR is returned.
+and \fBE_UNKNOWN_COMMAND\fP is returned.
This return value makes sense,
because a double click usually means that an field-specific action should
be returned.
application specific command should be executed.
.bP
If a translation
-into a request was done, \fBform_driver\fR returns the result of this request.
+into a request was done, \fBform_driver\fP returns the result of this request.
.RE
.PP
-If you clicked outside the user window or the mouse event could not be translated
-into a form request an \fBE_REQUEST_DENIED\fR is returned.
+If you clicked outside the user window
+or the mouse event could not be translated
+into a form request an \fBE_REQUEST_DENIED\fP is returned.
.SS Application-defined commands
.PP
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 \fBE_UNKNOWN_COMMAND\fR. Application-defined commands
-should be defined relative to \fBMAX_COMMAND\fR, the maximum value of these
+command and returns \fBE_UNKNOWN_COMMAND\fP. Application-defined commands
+should be defined relative to \fBMAX_COMMAND\fP, the maximum value of these
pre-defined requests.
.SH RETURN VALUE
-\fBform_driver\fR returns one of the following error codes:
+\fBform_driver\fP returns one of the following error codes:
.TP 5
.B E_OK
The routine succeeded.
.B E_INVALID_FIELD
Contents of field is invalid.
.TP 5
+.B E_NOT_CONNECTED
+No fields are connected to the form.
+.TP 5
.B E_REQUEST_DENIED
The form driver could not process the request.
.TP 5
.B E_SYSTEM_ERROR
-System error occurred (see \fBerrno\fR).
+System error occurred (see \fBerrno\fP(3)).
.TP 5
.B E_UNKNOWN_COMMAND
The form driver code saw an unknown request code.
.
.SH SEE ALSO
-\fBcurses\fR(3X),
-\fBform\fR(3X),
-\fBform_field_buffer\fR(3X),
-\fBform_field_validation\fR(3X),
-\fBform_fieldtype\fR(3X),
-\fBform_variables\fR(3X),
-\fBgetch\fR(3X).
+\fBcurses\fP(3X),
+\fBform\fP(3X),
+\fBform_fieldtype\fP(3X),
+\fBform_field_buffer\fP(3X),
+\fBform_field_validation\fP(3X),
+\fBform_variables\fP(3X),
+\fBgetch\fP(3X).
.SH NOTES
-The header file \fB<form.h>\fR automatically includes the header files
-\fB<curses.h>\fR.
+The header file \fB<form.h>\fP automatically includes the header files
+\fB<curses.h>\fP.
.SH PORTABILITY
-These routines emulate the System V forms library. They were not supported on
+These routines emulate the System V forms library.
+They were not supported on
Version 7 or BSD versions.
.SH AUTHORS
-Juergen Pfeifer. Manual pages and adaptation for new curses by Eric
-S. Raymond.
+Juergen Pfeifer.
+Manual pages and adaptation for new curses by Eric S. Raymond.
projects / ncurses.git / blobdiff