curs_scanw



curs_scanw(3)             OpenBSD Programmer's Manual            curs_scanw(3)


NAME

       scanw, wscanw, mvscanw, mvwscanw, vwscanw, vw_scanw - convert formatted
       input from a curses window


SYNOPSIS

       #include <curses.h>

       int scanw(char *fmt, ...);
       int wscanw(WINDOW *win, char *fmt, ...);
       int mvscanw(int y, int x, char *fmt, ...);
       int mvwscanw(WINDOW *win, int y, int x, char *fmt, ...);
       int vw_scanw(WINDOW *win, char *fmt, va_list varglist);
       int vwscanw(WINDOW *win, char *fmt, va_list varglist);


DESCRIPTION

       The scanw, wscanw and mvscanw routines are analogous to scanf [see
       scanf(3)].  The effect of these routines is as though wgetstr were
       called on the window, and the resulting line used as input for
       sscanf(3).  Fields which do not map to a variable in the fmt field are
       lost.

       The vwscanw and vw_scanw routines are analogous to vscanf.  They
       perform a wscanw using a variable argument list.  The third argument is
       a va_list, a pointer to a list of arguments, as defined in <stdarg.h>.


RETURN VALUE

       vwscanw returns ERR on failure and an integer equal to the number of
       fields scanned on success.

       Applications may use the return value from the scanw, wscanw, mvscanw
       and mvwscanw routines to determine the number of fields which were
       mapped in the call.


PORTABILITY

       The XSI Curses standard, Issue 4 describes these functions.  The
       function vwscanw is marked TO BE WITHDRAWN, and is to be replaced by a
       function vw_scanw using the <stdarg.h> interface.  The Single Unix
       Specification, Version 2 states that vw_scanw  is preferred to vwscanw
       since the latter requires including <varargs.h>, which cannot be used
       in the same file as <stdarg.h>.  This implementation uses <stdarg.h>
       for both, because that header is included in <curses.h>.

       Both XSI and The Single Unix Specification, Version 2 state that these
       functions return ERR or OK.  Since the underlying scanf can return the
       number of items scanned, and the SVr4 code was documented to use this
       feature, this is probably an editing error which was introduced in XSI,
       rather than being done intentionally.  Portable applications should
       only test if the return value is ERR, since the OK value (zero) is
       likely to be misleading.  One possible way to get useful results would
       be to use a "%n" conversion at the end of the format string to ensure
       that something was processed.


SEE ALSO

       curses(3), curs_getstr(3), curs_printw(3), scanf(3)

                                                                 curs_scanw(3)

[Unix Hosting | Open-Source | Contact Us]
[Engineering & Automation | Software Development | Server Applications]