NAME

       getstr, getnstr, wgetstr, wgetnstr, mvgetstr, mvgetnstr, mvwgetstr, mvwgetnstr - accept character strings
       from curses terminal keyboard

SYNOPSIS

       #include <curses.h>

       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);

DESCRIPTION

       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, followed by a NUL.

       wgetnstr  reads  at  most n characters, thus preventing a possible overflow of the input buffer.  Any at‐
       tempt 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 win‐
       dow.

       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.

       Characters input are echoed only if echo is currently on.  In that case, backspace is echoed as  deletion
       of the previous character (typically a left motion).

RETURN VALUE

       All  routines  return the integer ERR upon failure and an OK (SVr4 specifies only “an integer value other
       than ERR”) upon successful completion.

       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.

       This implementation provides an extension as well.  If a SIGWINCH interrupts the function, it will return
       KEY_RESIZE rather than OK or ERR.

       Functions  with a “mv” prefix first perform a cursor movement using wmove, and return an error if the po‐
       sition is outside the window, or if the window pointer is null.

NOTES

       Note that getstr, mvgetstr, and mvwgetstr may be macros.

PORTABILITY

       These functions are described in the XSI Curses standard, Issue 4.  They read single-byte characters  on‐
       ly.   The  standard  does not define any error conditions.  This implementation returns ERR if the window
       pointer is null, or if the lower-level wgetch(3X) 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).

       The functions getnstr, mvgetnstr, and mvwgetnstr were present but not documented in SVr4.

       X/Open  Curses,  Issue  5  (2007)  stated  that  these functions “read at most n bytes” but did not state
       whether the terminating NUL is counted in that limit.  X/Open Curses, Issue 7 (2009) changed that to  say
       they  “read  at  most  n-1 bytes” to allow for the terminating NUL.  As of 2018, some implementations do,
       some do not count it:

       •   ncurses 6.1 and PDCurses do not count the NUL in the given limit, while

       •   Solaris SVr4 and NetBSD curses count the NUL as part of the limit.

       •   Solaris xcurses provides both: its wide-character wget_nstr reserves a NUL, but its wgetnstr does not
           count the NUL consistently.

       In SVr4 curses, a negative value of n tells wgetnstr to assume that the caller's buffer is  large  enough
       to  hold the result, i.e., to act like wgetstr.  X/Open Curses does not mention this (or anything related
       to negative or zero values of n), however most implementations use the feature, with different limits:

       •   Solaris SVr4 curses and PDCurses limit the result to 255 bytes.  Other Unix systems than Solaris  are
           likely to use the same limit.

       •   Solaris xcurses limits the result to LINE_MAX bytes.

       •   NetBSD  7  assumes  no particular limit for the result from wgetstr.  However, it limits the wgetnstr
           parameter n to ensure that it is greater than zero.

           A comment in NetBSD's source code states that this is specified in SUSv2.

       •   ncurses (before 6.2) assumes no particular limit for the result from wgetstr, and treats the n  para‐
           meter of wgetnstr like SVr4 curses.

       •   ncurses  6.2  uses LINE_MAX, or a larger (system-dependent) value which the sysconf function may pro‐
           vide.  If neither LINE_MAX or sysconf is available, ncurses uses the POSIX value for LINE_MAX (a 2048
           byte limit).  In either case, it reserves a byte for the terminating NUL.

SEE ALSO

       ncurses(3NCURSES), getch(3NCURSES), curses_variables(3NCURSES).

                                                                                                getstr(3NCURSES)