legacy_coding(3X)                                          legacy_coding(3X)

NAME         top

       use_legacy_coding - override locale-encoding checks

SYNOPSIS         top

       #include <curses.h>

       int use_legacy_coding(int level);

DESCRIPTION         top

       The use_legacy_coding function is an extension to the curses library.
       It allows the caller to change the result of unctrl, and suppress
       related checks within the library that would normally cause
       nonprinting characters to be rendered in visible form.  This affects
       only 8-bit characters.

       The level parameter controls the result:

              0    the library functions normally, rendering nonprinting
                   characters as described in unctrl.

              1    the library ignores isprintf for codes in the range

              2    the library ignores isprintf for codes in the range
                   128-255.  It also modifies the output of unctrl, showing
                   codes in the range 128-159 as is.

RETURN VALUE         top

       If the screen has not been initialized, or the level parameter is out
       of range, the function returns ERR.  Otherwise, it returns the
       previous level: 0, 1 or 2.

PORTABILITY         top

       This routine is specific to ncurses.  It was not supported on Version
       7, BSD or System V implementations.  It is recommended that any code
       depending on ncurses extensions be conditioned using NCURSES_VERSION.

SEE ALSO         top


AUTHOR         top

       Thomas Dickey (to support lynx's font-switching feature).

COLOPHON         top

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