How to empty ("truncate") a file on linux that already exists and is protected in someway?

linux file command-line
Sumeet Pareek picture Sumeet Pareek · Mar 11, 2010 · Viewed 110.5k times · Source

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

R Samuel Klatchko picture R Samuel Klatchko · Mar 11, 2010

You have the noclobber option set. The error looks like it's from csh, so you would do:

cat /dev/null >! file

If I'm wrong and you are using bash, you should do:

cat /dev/null >| file

in bash, you can also shorten that to:

>| file

Related questions

Why no output is shown when using grep twice?

Basically I'm wondering why this doesn't output anything: tail --follow=name file.txt | grep something | grep something_else You can assume that it should produce output I have run another line to confirm cat file.txt | grep something | grep something_…

Read More
How can I remove the BOM from a UTF-8 file?

I have a file in UTF-8 encoding with BOM and want to remove the BOM. Are there any linux command-line tools to remove the BOM from the file? $ file test.xml test.xml: XML 1.0 document, UTF-8 Unicode (with BOM) text, …

Read More
How to create a file in Linux from terminal window?

What's the easiest way to create a file in Linux terminal?

Read More