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legacy_coding 3x 2024-09-14 ncurses 6.5 Library calls

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