X-Git-Url: http://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=man%2Fform_fieldtype.3x;h=767c3fcfafcdbe02f56d8e41c99eb42950def67a;hp=9ed4b9e11e041c2492fb4b1732942d48c147f8f5;hb=63d26709472433a4660c88461162252bf0e5fde8;hpb=71c0306f0824ef2b10c4c5813fb003db48f3012e

diff --git a/man/form_fieldtype.3x b/man/form_fieldtype.3x
index 9ed4b9e1..767c3fcf 100644
--- a/man/form_fieldtype.3x
+++ b/man/form_fieldtype.3x
@@ -1,6 +1,7 @@
 '\" t
 .\"***************************************************************************
-.\" Copyright (c) 1998-2006,2010 Free Software Foundation, Inc.              *
+.\" Copyright 2018-2019,2020 Thomas E. Dickey                                *
+.\" Copyright 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            *
@@ -27,77 +28,105 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
-.\" $Id: form_fieldtype.3x,v 1.15 2010/07/31 16:10:55 tom Exp $
+.\" $Id: form_fieldtype.3x,v 1.28 2020/12/12 17:11:21 tom Exp $
+.de bP
+.ie n  .IP \(bu 4
+.el    .IP \(bu 2
+..
 .TH form_fieldtype 3X ""
 .SH NAME
 \fBform_fieldtype\fR \- define validation-field types
 .SH SYNOPSIS
 \fB#include <form.h>\fR
+.sp
+\fBFIELDTYPE *new_fieldtype(\fP
+    \fBbool (* const \fP\fIfield_check\fP\fB)(FIELD *, const void *),\fP
+    \fBbool (* const \fP\fIchar_check\fP\fB)(int, const void *));\fP
 .br
-FIELDTYPE *new_fieldtype(
-    bool (* const field_check)(FIELD *, const void *),
-    bool (* const char_check)(int, const void *));
-.br
-int free_fieldtype(FIELDTYPE *fieldtype);
-.br
-int set_fieldtype_arg(
-    FIELDTYPE *fieldtype,
-    void *(* const make_arg)(va_list *),
-    void *(* const copy_arg)(const void *),
-    void  (* const free_arg)(void *));
-.br
-int set_fieldtype_choice(
-    FIELDTYPE *fieldtype,
-    bool (* const next_choice)(FIELD *, const void *),
-    bool (* const prev_choice)(FIELD *, const void *));
-.br
-FIELDTYPE *link_fieldtype(FIELDTYPE *type1,
-                          FIELDTYPE *type2);
+\fBint free_fieldtype(FIELDTYPE *\fP\fIfieldtype\fP\fB);\fP
+.sp
+\fBint set_fieldtype_arg(\fP
+    \fBFIELDTYPE *\fP\fIfieldtype\fP\fB,\fP
+    \fBvoid *(* const \fP\fImake_arg\fP\fB)(va_list *),\fP
+    \fBvoid *(* const \fP\fIcopy_arg\fP\fB)(const void *),\fP
+    \fBvoid  (* const \fP\fIfree_arg\fP\fB)(void *));\fP
 .br
+\fBint set_fieldtype_choice(\fP
+    \fBFIELDTYPE *\fP\fIfieldtype\fP\fB,\fP
+    \fBbool (* const \fP\fInext_choice\fP\fB)(FIELD *, const void *),\fP
+    \fBbool (* const \fP\fIprev_choice\fP\fB)(FIELD *, const void *));\fP
+.sp
+\fBFIELDTYPE *link_fieldtype(FIELDTYPE *\fP\fItype1\fP\fB,\fP
+                          \fBFIELDTYPE *\fP\fItype2\fP\fB);\fP
 .SH DESCRIPTION
+.SS new_fieldtype
 The function \fBnew_fieldtype\fR creates a new field type usable for data
-validation.  You supply it with \fIfield_check\fR, a predicate to check the
+validation.
+Its parameters are function pointers:
+.TP 5
+\fIfield_check\fR
+This function checks the
 validity of an entered data string whenever the user attempts to leave a field.
+It has two arguments:
+.RS
+.bP
 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
+field's buffer, sizes and other attributes.
+.bP
+The second argument is an
 argument-block structure, about which more below.
+.RE
+.TP 5
+\fIchar_check\fR
+This function validates input characters as they are entered.
+The form library passes it the character to be checked
+and a pointer to an argument-block structure.
+.SS free_fieldtype
 .PP
-You also supply \fBnew_fieldtype\fR with \fIchar_check\fR,
-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.
-.PP
-The function \fBfree_fieldtype\fR frees the space allocated for a given
-validation type.
+The \fBfree_fieldtype\fR function
+frees the space allocated for a given validation type by \fBnew_fieldtype\fP.
+.SS set_fieldtype_arg
 .PP
-The function \fBset_fieldtype_arg\fR associates three storage-management functions
-with a field type.
-The \fImake_arg\fR function is automatically applied to the
+The function \fBset_fieldtype_arg\fR associates
+three storage-management functions with a field type:
+.TP 5
+\fImake_arg\fR
+This function is automatically applied to the
 list of arguments you give \fBset_field_type\fR when attaching validation
-to a field; its job is to bundle these into an allocated argument-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 \fImake_arg\fR function,
-the other two are optional, you may supply NULL for them.
-In this case it is assumed
+to a field.
+It stores the arguments in an allocated argument-block
+object which is used when validating input.
+.TP 5
+\fIcopy_arg\fR
+This function may be used by applications to copy argument-blocks.
+.TP 5
+\fIfree_arg\fR
+Frees an argument-block structure.
+.PP
+You must supply the \fImake_arg\fR function.
+The other two are optional: you may supply NULL for them.
+In this case, the form library assumes
 that \fImake_arg\fR does not allocate memory but simply loads the
 argument into a single scalar value.
-.PP
-The function \fBlink_fieldtype\fR creates
-a new field type from the two given types.
-They are connected by an logical 'OR'.
+.SS set_fieldtype_choice
 .PP
 The form driver requests \fBREQ_NEXT_CHOICE\fR and \fBREQ_PREV_CHOICE\fR 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.
+.PP
 The \fBset_fieldtype_choice\fR
 function 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.
+.SS link_fieldtype
+.PP
+The function \fBlink_fieldtype\fR creates
+a new field type from the two given types.
+They are connected by an logical 'OR'.
 .SH RETURN VALUE
 The pointer-valued routines return NULL on error.
-They set errno according to their success:
+They set \fBerrno\fP according to their success:
 .TP 5
 .B E_OK
 The routine succeeded.
@@ -124,25 +153,18 @@ The field is already connected to a form.
 The field is the current field.
 .TP 5
 .B E_SYSTEM_ERROR
-System error occurred (see \fBerrno\fR).
+System error occurred (see \fBerrno\fR(3)).
 .SH SEE ALSO
-\fBcurses\fR(3X), \fBform\fR(3X).
+\fBcurses\fR(3X),
+\fBform\fR(3X),
+\fBform_field_validation\fR(3X).
 .SH NOTES
 The header file \fB<form.h>\fR automatically includes the header file
 \fB<curses.h>\fR.
-.PP
-All of the \fB(char *)\fR arguments of these functions should actually be
-\fB(void *)\fR.  The type has been left uncorrected for strict compatibility
-with System V.
 .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.
-.\"#
-.\"# The following sets edit modes for GNU EMACS
-.\"# Local Variables:
-.\"# mode:nroff
-.\"# fill-column:79
-.\"# End:
+Juergen Pfeifer.
+Manual pages and adaptation for new curses by Eric S. Raymond.