The hyphen means “STDIN until EOF”, a pipe or redirection sets the source and the hyphen instructs where to place it.
echo "long text..." | flyctl secrets set LONG_TEXT=-
flyctl secrets set FROM_A_FILE=- < file.txt
The hyphen means “STDIN until EOF”, a pipe or redirection sets the source and the hyphen instructs where to place it.
echo "long text..." | flyctl secrets set LONG_TEXT=-
flyctl secrets set FROM_A_FILE=- < file.txt