MirBSD manpage: field_arg(3), field_type(3), form_field_validation(3), set_field_type(3)

form_field_validationUNIX Programmer's Maform_field_validation(3)

NAME

     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);

     FIELDTYPE *TYPE_ALNUM;
     FIELDTYPE *TYPE_ALPHA;
     FIELDTYPE *TYPE_ENUM;
     FIELDTYPE *TYPE_INTEGER;
     FIELDTYPE *TYPE_NUMERIC;
     FIELDTYPE *TYPE_REGEXP;
     FIELDTYPE *TYPE_IPV4;

DESCRIPTION

     The function set_field_type declares a data type for a given
     form field. This is the type checked by validation func-
     tions. 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 par-
          tial 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

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form_field_validationUNIX Programmer's Maform_field_validation(3)

          handling see printf's man-page.

     TYPE_NUMERIC
          Numeric data (may have a decimal-point part). Requires
          a third int argument controlling the precision, a
          fourth double argument constraining minimum value, and
          a fifth double constraining maximum value. If your sys-
          tem 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 han-
          dling see printf's man-page.

     TYPE_REGEXP
          Regular expression data.  Requires a regular expression
          (char *) third argument; the data is valid if the regu-
          lar expression matches it.  Regular expressions are in
          the format of regcomp(3) and regexec(3). 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]*$" always means that you
          have to fill all eight positions with digits. If you
          want to allow fewer digits, you may use for example
          "^[0-9]* *$" 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(3) manual page.

RETURN VALUE

     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).

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form_field_validationUNIX Programmer's Maform_field_validation(3)

SEE ALSO

     curses(3), form(3).

NOTES

     The header file <form.h> automatically includes the header
     file <curses.h>.

PORTABILITY

     These routines emulate the System V forms library.  They
     were not supported on Version 7 or BSD versions.

AUTHORS

     Juergen Pfeifer.  Manual pages and adaptation for new curses
     by Eric S. Raymond.

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