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 function, new_field, dup_field, link_field return NULL on error.
The function free_field returns one of the following: