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Ask user to confirm

Terminal - Ask user to confirm
Confirm() { read -sn 1 -p "$1 [Y/N]? "; [[ $REPLY = [Yy] ]]; }
2010-11-22 11:01:14
User: frans
Functions: read
11
Ask user to confirm

Returns true if user presses the key.

Use it like

Confirm "Continue" && do action

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
Confirm() { echo -n "$1 [y/n]? " ; read reply; case $reply in Y*|y*) true ;; *) false ;; esac }
2010-11-22 16:54:16
User: eikenberry
Functions: echo false read true
Tags: read
2

This version works across on all POSIX compliant shell variants.

Know a better way?

If you can do better, submit your command here.

What others think

It's usually good UI to display the response so the user can confirm that he really did press the wrong key so I would recommend leaving of the -s.

If you'd like to have an echo after the prompt so the next output is not on the same line as the prompt, you can do one of these:

confirm() { read -n 1 -p "$1 [Y/N]? "; [[ $REPLY = [Yy] ]] && echo || { echo; return 1;} } confirm() { read -n 1 -p "$1 [Y/N]? "; [[ $REPLY = [Yy] ]]; local r=$?; echo; return $r; }
Comment by dennisw 235 weeks ago

The fact is that in scripts where i used that, i used the verbosity of the involved action like:

Confirm "Delete files" && rm -v $Files || echo "cancelled"
Comment by frans 235 weeks ago

how do i halt the script if user pressed N at

Confirm() { read -sn 1 -p "$1 [Y/N]? "; [[ $REPLY = [Yy] ]]; } Confirm "Continue?"
Comment by rubo77 181 weeks and 5 days ago

if you mean 'exit', then it's simply:

Confirm "Continue" || exit

The "?" is already in the function so there's no need to pass it in the parameter.

Comment by frans 181 weeks and 5 days ago

Your point of view

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