why does readline think I am pressing the "d" key?

Question

I have two scripts. test4.sh calls 1.sh
I don't understand why 1.sh things I am pressing the “d” key. Can you explain please

Here is 1.sh

set -x
echo "Please enter some input: "
echo "enter $(echo $RANDOM)"
sleep 2
read input_variable
echo "You entered: $input_variable"

Here is test4.sh

set -x
set +e
mkfifo p_in
bash 1.sh p_in<0 | sed -e 's/^/1\.sh:: /'  &
cat - 1> p_in

Output:

pi@raspberrypi:~/tmp/lolttt $ bash test4.sh
+ set +e
+ mkfifo p_in
mkfifo: cannot create fifo 'p_in': File exists
+ bash 1.sh p_in
+ cat -
+ sed -e 's/^/1\.sh:: /'
+ echo 'Please enter some input: '
1.sh:: Please enter some input:
++ echo 23876
+ echo 'enter 23876'
1.sh:: enter 23876
+ sleep 2
+ read input_variable
+ echo 'You entered: d'
1.sh:: You entered: d

This weird behaviour does not happen if I run 1.sh directly from bash. This weird behaviour only happens from test4.sh

Help please?

Answer 1

Because you have a file named 0 in your current working directory with the content d .

bash 1.sh p_in<0 - is equal to bash 1.sh p_in <0 - runs command 1.sh with argument p_in with file named 0 redirected to standard input.

I think you want bash 1.sh 0<p_in . On the left is file descriptor. Or just <p_in without 0, the default input is file descriptor 0.