Для вторичных сервисов DNS я использую afraid.org и buddyns.com; оба освобождают.
Test the file instead.
test -e /etc/shadow && echo The file is there
test -f /etc/shadow && echo The file is a file
test -d /etc/shadow && echo Oops, that file is a directory
test -r /etc/shadow && echo I can read the file
test -w /etc/shadow && echo I can write the file
See the test
man page for other possibilities.