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Re: Backspace echoed incorrectly with TERM=garbage

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From achurch@achurch.org (Andrew Church)
Newsgroups gnu.bash.bug
Subject Re: Backspace echoed incorrectly with TERM=garbage
Date Fri, 19 Jun 2020 13:30:38 +0900
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>But I thought of 'strace'.  I attached that to the Bash process and
>clearly saw it sending only space characters, no backspaces:
>
>pselect6(1, [0], NULL, NULL, NULL, {[], 8}) = 1 (in [0])
>read(0, "q", 1)                         = 1
>write(2, " ", 1)                        = 1

I can reproduce this behavior, using bash 4.4(23) and readline 7.0(5):

read(0, "\177", 1)                      = 1
write(2, " ", 1)                        = 1

I also have ncurses-6.2, with readline linking directly to libtinfo.
If I link readline against ncurses-5.9 (forcing -lncurses), the problem
goes away:

read(0, "\177", 1)                      = 1
write(2, "\10 \10", 3)                  = 3

So the problem may be either in ncurses itself or in readline's
interaction with ncurses/libtinfo.

  --Andrew Church
    http://achurch.org/

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Re: Backspace echoed incorrectly with TERM=garbage achurch@achurch.org (Andrew Church) - 2020-06-19 13:30 +0900

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