There is a program like this:
while true
do
echo 'Your pass: '
read password
if [ $password == 'qwerty' ]; then
echo 'Nice!'
break
fi
done
I can use xargs only if the program has arguments. But in this case ./program.sh password doesn't work.
I have a list of password and I need to send them in loop to this program.
xargs -a list ./program.sh doesn't work.
There's no reason to use xargs here, you can simply do:
while IFS= read -r password
do
if [ "$password" = 'qwerty' ]; then
echo 'Nice!'
break
fi
done
And then run it as:
./program.sh < list
If you really want xargs, you can do something like:
for password do
case "$password" in
'qwerty')
echo 'Nice!'
;;
esac
done
And then:
xargs -rd '\n' -a list ./program.sh
"$@" though? Is $@ not portable? And why have them on the same line and without a ; before do?
for i do is the Bourne/POSIX<2016 syntax. for i\ndo is the most portable if you ever come across ancient BSDs. for i; do is now also standard with the 2016 edition of the standard. for i in "$@" has a number of issues with a number of shells in corner cases. It's discussed in some Q&A here I beleive.
-a, -r nor -d are standard xargs options.
for i in "$@"; do vs for i; do. It sounds very interesting, as I thought they'd have an identical effect. Would you do the favour of linking it for all of us?
Nice!if the user entersqwerty, but also if they enter" qwerty "(leading or trailing space or tabs with the default value of$IFS) orq\w\e\r\t\y... See Understanding "IFS= read -r line", and also if they enter-d / -o yas your forgot to quote$password.stty -echobefore thereadandstty echoafter it, so the password is not displayed in the terminal.