curs_instr.3x man page
instr, innstr, winstr, winnstr, mvinstr, mvinnstr, mvwinstr, mvwinnstr — get a string of characters from a curses window
int instr(char *str);
int innstr(char *str, int n);
int winstr(WINDOW *win, char *str);
int winnstr(WINDOW *win, char *str, int n);
int mvinstr(int y, int x, char *str);
int mvinnstr(int y, int x, char *str, int n);
int mvwinstr(WINDOW *win, int y, int x, char *str);
int mvwinnstr(WINDOW *win, int y, int x, char *str, int n);
These routines return a string of characters in str, extracted starting at the current cursor position in the named window. Attributes are stripped from the characters. The four functions with n as the last argument return a leading substring at most n characters long (exclusive of the trailing NUL).
All of the functions return ERR upon failure, or the number of characters actually read into the string.
X/Open defines no error conditions. In this implementation, if the window parameter is null or the str parameter is null, a zero is returned.
Functions with a "mv" prefix first perform a cursor movement using wmove, and return an error if the position is outside the window, or if the window pointer is null.
Note that all routines except winnstr may be macros.
SVr4 does not document whether a length limit includes or excludes the trailing NUL.
The ncurses library extends the XSI description by allowing a negative value for n. In this case, the functions return the string ending at the right margin.