- The function set_field_type declares a data type for a
- given form field. This is the type checked by validation
- functions. The predefined types are as follows:
-
- TYPE_ALNUM
- Alphanumeric data. Requires a third int argument, a
- minimum field width.
-
- TYPE_ALPHA
- Character data. Requires a third int argument, a
- minimum field width.
-
- TYPE_ENUM
- Accept one of a specified set of strings. Requires a
- third (char**) argument pointing to a string list; a
- fourth int flag argument to enable case-sensitivity;
- and a fifth int flag argument specifying whether a
- partial match must be a unique one (if this flag is
- off, a prefix matches the first of any set of more
- than one list elements with that prefix). Please
- notice that the string list is not copied, only a
- reference to it is stored in the field. So you should
- avoid using a list that lives in automatic variables
- on the stack.
-
- TYPE_INTEGER
- Integer data, parsable to an integer by atoi(3).
- Requires a third int argument controlling the preci-
- sion, a fourth long argument constraining minimum
- value, and a fifth long constraining maximum value.
- If the maximum value is less than or equal to the
- minimum value, the range is simply ignored. On return
- the field buffer is formatted according to the printf
- format specification ".*ld", where the '*' is
- replaced by the precision argument. For details of
- the precision handling see printf's man-page.
-
- TYPE_NUMERIC
- Numeric data (may have a decimal-point part).
- Requires a third int argument controlling the preci-
- sion, a fourth double argument constraining minimum
- value, and a fifth double constraining maximum value.
- If your system supports locales, the decimal point
- character to be used must be the one specified by
- your locale. If the maximum value is less than or
- equal to the minimum value, the range is simply
- ignored. On return the field buffer is formatted
- according to the printf format specification ".*f",
- where the '*' is replaced by the precision argument.
- For details of the precision handling see printf's
- man-page.
-
- TYPE_REGEXP
- Regular expression data. Requires a regular expres-
- sion (char*) third argument; the data is valid if
- the regular expression matches it. Regular expres-
- sions are in the format of regcomp and regexec.
- Please notice that the regular expression must match
- the whole field. If you have for example an eight
- character wide field, a regular expression "^[0-9]*$"
- always means that you have to fill all eight posi-
- tions with digits. If you want to allow fewer digits,
- you may use for example "^[0-9]* *$" which is good
- for trailing spaces (up to an empty field), or "^
- *[0-9]* *$" which is good for leading and trailing
- spaces around the digits.
-
- TYPE_IPV4
- An Internet Protocol Version 4 address. This requires
- no additional argument. It is checked whether or not
- the buffer has the form a.b.c.d, where a,b,c and d
- are numbers between 0 and 255. Trailing blanks in the
- buffer are ignored. The address itself is not vali-
- dated. Please note that this is an ncurses extension.
- This field type may not be available in other curses
- implementations.
-
- It is possible to set up new programmer-defined field
- types. See the form_fieldtype(3x) manual page.
+
+ By default, no validation is done on form fields. You can associate a
+ form with with a fieldtype, making the form library validate input.
-
-
RETURN VALUE
- The functions field_type and field_arg return NULL on
- error. The function set_field_type returns one of the fol-
- lowing:
- E_OK The routine succeeded.
+
+ Returns a pointer to the field's argument block. The argumentblock is
+ an opaque structure containing a copy of the arguments provided in a
+ set_field_type call.
- E_SYSTEM_ERROR
- System error occurred (see errno).
+
+ The function set_field_type associates a field type with a given form
+ field. This is the type checked by validation functions. Most field
+ types are configurable, via arguments which the caller provides when
+ calling set_field_type.
-
-
NOTES
- The header file <form.h> automatically includes the header
- file <curses.h>.
+ Several field types are predefined by the form library.
-
-
PORTABILITY
- These routines emulate the System V forms library. They
- were not supported on Version 7 or BSD versions.
+
+ It is possible to set up new programmer-defined field types. Field
+ types are implemented via the FIELDTYPE data structure, which contains
+ several pointers to functions.
+ See the form_fieldtype(3x) manual page, which describes functions which
+ can be used to construct a field-type dynamically.
-
-
AUTHORS
- Juergen Pfeifer. Manual pages and adaptation for new
- curses by Eric S. Raymond.
+ The predefined types are as follows:
+
+
+
+ Accept one of a specified set of strings. Required parameters:
+
+ o a third (char**) argument pointing to a string list;
+
+ o a fourth int flag argument to enable case-sensitivity;
+
+ o a fifth int flag argument specifying whether a partial match must
+ be a unique one. If this flag is off, a prefix matches the first
+ of any set of more than one list elements with that prefix.
+
+ The library copies the string list, so you may use a list that lives in
+ automatic variables on the stack.
+
+
+
+ Integer data, parsable to an integer by atoi(3). Required parameters:
+
+ o a third int argument controlling the precision,
+
+ o a fourth long argument constraining minimum value,
+
+ o a fifth long constraining maximum value. If the maximum value is
+ less than or equal to the minimum value, the range is simply
+ ignored.
+
+ On return, the field buffer is formatted according to the printf format
+ specification ".*ld", where the "*" is replaced by the precision
+ argument.
+
+ For details of the precision handling see printf(3).
+
+
+
+ Numeric data (may have a decimal-point part). Required parameters:
+
+ o a third int argument controlling the precision,
+
+ o a fourth double argument constraining minimum value,
+
+ o and a fifth double constraining maximum value. If your system
+ supports locales, the decimal point character must be the one
+ specified by your locale. If the maximum value is less than or
+ equal to the minimum value, the range is simply ignored.
+
+ On return, the field buffer is formatted according to the printf format
+ specification ".*f", where the "*" is replaced by the precision
+ argument.
+
+ For details of the precision handling see printf(3).
+
+
+
+ Regular expression data. Required parameter:
+
+ o a third argument, a regular expression (char*) string. The data
+ is valid if the regular expression matches it.
+
+ Regular expressions are in the format of regcomp and regexec.
+
+ The regular expression must match the whole field. If you have for
+ example, an eight character wide field, a regular expression "^[0-9]*$"
+ always means that you have to fill all eight positions with digits. If
+ you want to allow fewer digits, you may use for example "^[0-9]* *$"
+ which is good for trailing spaces (up to an empty field), or "^ *[0-9]*
+ *$" which is good for leading and trailing spaces around the digits.
+
+
+
+ An Internet Protocol Version 4 address. Required parameter:
+
+ o none
+
+ The form library checks whether or not the buffer has the form a.b.c.d,
+ where a, b, c, and d are numbers in the range 0 to 255. Trailing
+ blanks in the buffer are ignored. The address itself is not validated.
+
+ This is an ncurses extension; this field type may not be available in
+ other curses implementations.
+
+
+
+ The functions field_type and field_arg return NULL on error. The
+ function set_field_type returns one of the following:
+
+ E_OK The routine succeeded.
+
+ E_SYSTEM_ERROR
+ System error occurred (see errno(3)).
+
+
+