legacy_coding(3X)                Library calls               legacy_coding(3X)

NAME
       use_legacy_coding - override curses locale encoding checks

SYNOPSIS
       #include <curses.h>

       int use_legacy_coding(int level);

DESCRIPTION
       use_legacy_coding, an ncurses extension to the curses library, permits
       customiztion of unctrl(3X) behavior, suppressing isprint(3)-based
       checks within the library that would normally cause nonprinting
       characters to be rendered in visible form.  The alteration affects only
       byte-wide characters with the most significant bit set.

       The level parameter controls the result.

              0    The library functions normally, rendering nonprinting
                   characters as described in unctrl(3X),

              1    the library ignores isprint for codes in the range 160-255.

              2    the library ignores isprint for codes in the range 128-255.
                   It also modifies the output of unctrl(3X), showing codes in
                   the range 128-159 as is.

RETURN VALUE
       If the curses screen has not been initialized, or the level parameter
       is out of range, use_legacy_coding returns ERR.  Otherwise, it returns
       the previous level.

EXTENSIONS
       use_legacy_coding is an ncurses extension.

PORTABILITY
       Applications employing ncurses extensions should condition their use on
       the visibility of the NCURSES_VERSION preprocessor macro.

HISTORY
       ncurses 5.6 (2006) introduced use_legacy_coding to support lynx(1)'s
       font-switching feature.

AUTHORS
       Thomas Dickey

SEE ALSO
       unctrl(3X)

ncurses 6.6                       2024-09-14                 legacy_coding(3X)