new_field, dup_field, link_field, free_field - create and destroy form fields
#include <form.h> FIELD *new_field(int height, int width, int toprow, int leftcol, int offscreen, int nbuffers); FIELD *dup_field(FIELD *field, int toprow, int leftcol); FIELD *link_field(FIELD *field, int toprow, int leftcol); int free_field(FIELD *field);
The function new_field allocates a new field and initializes it from the parameters given: height, width, row of upper-left corner, column of upper-left corner, number off-screen rows, and number of additional working buffers. The function dup_field duplicates a field at a new location. Most attributes (including current contents, size, validation type, buffer count, growth threshold, justification, foreground, background, pad character, options, and user pointer) are copied. Field status and the field page bit are not copied. The function link_field acts like dup_field, but the new field shares buffers with its parent. Attribute data is separate. The function free_field de-allocates storage associated with a field.
The functions new_field, dup_field, link_field return NULL on error. They set errno according to their success: E_OK The routine succeeded. E_BAD_ARGUMENT Routine detected an incorrect or out-of-range argument. E_SYSTEM_ERROR System error occurred, e.g., malloc failure. The function free_field returns one of the following: E_OK The routine succeeded. E_BAD_ARGUMENT Routine detected an incorrect or out-of-range argument. E_CONNECTED field is connected.
The header file <form.h> automatically includes the header file <curses.h>.
These routines emulate the System V forms library. They were not supported on Version 7 or BSD versions. It may be unwise to count on the set of attributes copied by dup_field being portable; the System V forms library documents are not very explicit about what gets copied and what does not.
Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S. Raymond. form_field_new(3x)