mvwgetnstr – accept character strings from curses terminal keyboard
int getstr(char *str);
int getnstr(char *str, int n);
int wgetstr(WINDOW *win, char *str);
int wgetnstr(WINDOW *win, char *str, int n);
int mvgetstr(int y, int x, char *str);
int mvwgetstr(WINDOW *win, int y, int x, char *str);
int mvgetnstr(int y, int x, char *str, int n);
int mvwgetnstr(WINDOW *, int y, int x, char *str, int n);
The function getstr is equivalent to a series of calls to getch,
until a newline or carriage return is received (the terminating character is
not included in the returned string). The resulting value is placed in the
area pointed to by the character pointer str.
wgetnstr reads at most n characters, thus preventing a possible
overflow of the input buffer. Any attempt to enter more characters (other
than the terminating newline or carriage return) causes a beep. Function
keys also cause a beep and are ignored. The getnstr function reads
from the stdscr default window.
The user’s erase and kill characters are interpreted. If keypad
mode is on for the window, KEY_LEFT and KEY_BACKSPACE
are both considered equivalent to the user’s kill character.
All routines return the integer ERR upon failure and an OK (SVr4
specifies only "an integer value other than ERR") upon successful
X/Open defines no error conditions.
In this implementation,
these functions return an error
if the window pointer is null, or
if its timeout expires without having any data.
These functions are described in the XSI Curses standard, Issue 4.
They read single-byte characters only.
The standard does not define any error conditions.
This implementation returns ERR if the window pointer is null,
or if the lower-level wgetch call returns an ERR.
SVr3 and early SVr4 curses implementations did not reject function keys;
the SVr4.0 documentation claimed that "special keys" (such as function
keys, "home" key, "clear" key, etc.) are "interpreted", without
giving details. It lied. In fact, the `character’ value appended to the
string by those implementations was predictable but not useful
(being, in fact, the low-order eight bits of the key’s KEY_ value).