- form_field_validation - data type validation for fields
-
-
-
-
SYNOPSIS
- #include<form.h>
- int set_field_type(FIELD *field, FIELDTYPE *type, ...);
- FIELDTYPE *field_type(const FIELD *field);
- void *field_arg(const FIELD *field);
-
-
-
-
DESCRIPTION
- The function set_field_type declares a data type for a
- given form field. This is the type checked by validation
- functions. The 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.
+form_field_validation(3x) Library calls form_field_validation(3x)
- 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 to use 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 or equal 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 locale's, the decimal point
- character to be used must be the one specified by
- your locale. If the maximum value is less or equal
- 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(3x) and
- regexec(3x). Please notice that the regular expres-
- sion 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.
- 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.
+
+ 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.
-
-
PORTABILITY
- These routines emulate the System V forms library. They
- were not supported on Version 7 or BSD versions.
+
+ 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.
+ Several field types are predefined by the form library.
+
+ 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.
+ The predefined types are as follows:
+ TYPE_ALNUM
+ Alphanumeric data. Required parameter:
+ o a third int argument, a minimum field width.
+ TYPE_ALPHA
+ Character data. Required parameter:
+ o a third int argument, a minimum field width.
+ TYPE_ENUM
+ 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.
+ TYPE_INTEGER
+ 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).
+ TYPE_NUMERIC
+ 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).
+ TYPE_REGEXP
+ 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.
+ TYPE_IPV4
+ 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)).
+