How to empty (“truncate”) a file on linux that alr

Question

I have a file called error.log on my server that I need to frequently truncate. I have rw permissions for the file. Opening the file in vi > deleting all content > saving works (obviously). But when I try the below

cat /dev/null > error.log

I get the message

File already exists.

Obviously there is some kind of configuration done on the server to prevent accidental overriding of files. Can anybody tell how do I "truncate" the file in a single command?

Answer 1

the credit goes for my senior colleague for this:

:> filename

This will not break log files, so you can even use it on syslog, for example.

Answer 2

Since sudo will not work with redirection >, I like the tee command for this purpose

echo "" | sudo tee fileName

Answer 3

This will be enough to set the file size to 0:

> error.log

Answer 4

false|tee fileToTruncate

may work as well

Answer 5

You can try also:

echo -n > /my/file

Answer 6

You can also use function truncate

$truncate -s0 yourfile

if permission denied, use sudo

$sudo truncate -s0 yourfile

Help/Manual: man truncate

tested on ubuntu Linux